Honeywell SuitePRO Digital Fan Coil Thermostats Installation Guide

: June 7, 2024
: Honeywell

Table of Contents

SuitePRO Digital Fan Coil Thermostats
2) selection. For example, only when you select the value 3 or 6 for the
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SuitePRO Digital Fan Coil Thermostats

TB6575/TB8575 SuitePROTM Digital Fan Coil Thermostats

INSTALLATION INSTRUCTIONS
The fan is controlled from the thermostat. The low, medium, high, or auto fan settings are easily made with a press of a key.
Valves and auxiliary electric heaters can be controlled using a relay or contactor controlled by the system switch.

READ BEFORE INSTALLING
PRODUCT DESCRIPTION
The SuitePROTM is a family of digital fan coil thermostats for residential and commercial applications such as hotels, condominiums, school classrooms, etc.
Four models are available for your application: · TB6575A1000: 2-pipe or 4-pipe with
seasonal/manual/automatic heat/cool changeover; 120 Vac/240 Vac. · TB6575B1000: 2-pipe only with seasonal or manual heat/cool changeover; 120 Vac/240 Vac. · TB6575C1000: 2-pipe or 4-pipe with seasonal/manual/automatic heat/cool changeover; 120 Vac/240 Vac/277 Vac. · TB8575A1000: 2-pipe or 4-pipe with seasonal heat/cool changeover; 24 Vac.
All four models are suitable for multiple applications. Changes in output wiring and external links between wiring terminals allow you to configure the thermostat for the appropriate application.
The applications that are available are: · Heating or cooling only · Two pipes: heat or cool with manual changeover · Two pipes: heat or cool with seasonal changeover
(requires optional pipe sensor) · Two pipes: heat or cool with auxiliary heat and
manual or seasonal changeover (requires optional pipe sensor) · Four pipes: mixed manual and auto changeover · Four pipes: manual changeover · Four pipes: auto changeover

FEATURES
· Simple, intuitive user interface. · Pre-installed lead wires for fast installation
(TB6575A, TB6575B and TB6575C models only)
· Backlight display permits easy viewing in any light.
· Four buttons allow manual control of system operation, fan speed, and temperature setpoint adjustment.
· Digital display of ambient temperature, setpoint, heating or cooling mode, fan status, and remote setback
· Proportional plus Integral (P+I) control algorithm for precision temperature regulation.
· Single Setpoint and Heat/Cool setpoint methods for 4-pipe Auto Changeover.
· Adjustable maximum heating and minimum cooling setpoint limits using range stops.
· EEPROM permanently retains user settings, including setpoints, during power loss (no batteries required).
· Selectable °C or °F display via Setup button on thermostat.
· Displayable pipe sensor temperature readout to aid in troubleshooting.
· Selectable to allow the fan motor to always begin on high speed to ensure sufficient torque at startup.
· Option to wire a remote indoor temperature sensor.
· Freeze protect algorithm turns on heat when needed.
· Economy Setback options via dry contact or Activity Sensing
· Advanced fan control with VersaSpeedTM fan ramp algorithm and Auto Fan Reset

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TB6575/TB8575 SUITEPROTM DIGITAL FAN COIL THERMOSTATS

SPECIFICATIONS

Supply Voltages:
TB6575A1000 and TB6575B1000: · 120 Vac ±10% at 50Hz/60Hz
· 240 Vac -15% to +10% at 50Hz/60Hz
TB6575C1000: · 120 Vac/240 Vac/277 Vac ±10% at 50Hz/60Hz
TB8575A1000: · 20 Vac to 30 Vac at 50/60Hz (using 24 Vac, Class 2, NEMA rated transformer)
Safety Fuse: TB6575A1000 and TB6575B1000 use 15A 250 Vac fuse. TB6575C1000 uses a 15A 350 Vac fuse. If the safety fuse blows, the thermostat must be replaced. The fuse is not field replaceable.

Electrical Ratings: (see Table 1).

Table 1. Electrical Ratings.

Component Fan Relay Heat/Cool Relay

24 Vac 1.0 A 1.0 A

Amps (inductive) for:

120 Vac 240 Vac 277 Vac

6.0 A

3.0 A

2.4 A

1.0 A

Environmental Ratings: Temperature: Operating Range: 18°C to 49°C (0°F to 120°F). Shipping and Storage Range: -29°C to 49°C (-20°F to 120°F). Humidity: 5% to 90% RH, non-condensing.

Onboard Temperature Sensor: Type: 10K NTC Working Range: 18°C to 49°C (0°F to 120°F) Display Range: 0°C to 37°C (32°F to 99°F) Accuracy ±2.0°F at 70°F

Remote Temperature Sensor (optional): Type: 20K NTC Working Range: 18°C to 49°C (0°F to 120°F) Display Range: 0°C to 37°C (32°F to 99°F) Accuracy ±2.0°F at 70°F

Remote Pipe Sensor (optional): Type: 20K NTC Working Range: 0°C to 93°C (32°F to 199°F) Display Range: 0°C to 93°C (32°F to 199°F) Accuracy ±5.0°F over the temperature sensing range

Remote Setback Input: Dry contact, maximum resistance of 100 ohms. TB6575 9Vdc, < 4 mA; TB8575 16 Vdc, < 5 mA. Note Electrical WARNING on page 3.

Remote Setback Range: Heating: 10°C to 21°C (50°F to 70°F). Cooling: 22°C to 32°C (72°F to 90°F).

Enclosure: Plastic (cover, sub-base, and optional adaptor plate)
Junction Box Mounting: Direct mounting on a horizontal single gang NEMA 2 in. (50.8 mm) x 4 in. (101.6 mm) surface mount electrical box, or on 4 in. (101.6 mm) x 4 in. (101.6 mm) box or vertical 2 in. (50.8 mm) x 4 in. (101.6 mm) surface mount electrical box with the optional 50033847-001 adapter plate.
Dimensions: See Fig. 1 on page 3.
Wiring: 11 screw-in terminals located on the sub-base capable of accepting up to 2 x 18 AWG (0.8 sq. mm), 1 x 16 AWG (1.3 sq. mm), or 1 x 14 AWG (2.1 sq. mm) wires. Accepts stranded or unstranded 14-28 gauge wire.
NOTES: 1. The TB6575A1000 and TB6575C1000 models are pre-fitted with color- coded fly leads (16 AWG) attached to seven terminals. 2. The TB6575B1000 model is pre-fitted with color-coded fly leads (16 AWG) attached to six terminals. 3. The TB8575A1000 model does not have fly leads attached to any terminals. 4. See Table 3 on page 6 for fly lead usage.
Minimum Operational Life (at maximum load): Thermostat contacts: 100,000 cycles
Approvals: CSA Certified C/US for Canada and the U.S.A. Meets the same requirements as UL-873. FCC Part 15 Class B
Accessories:
· 50033847-001 adapter plate for mounting on a vertical 2 in. (50.8 mm) x 4 in. (101.6 mm) singlegang or double-gang NEMA standard vertical switch box (6 1/4 in. (158 mm) x 5 1/16 in. (128 mm) x 13/22 in. (10 mm)).
· TR21 20K Ohm NTC non-linear remote temperature sensor. Other acceptable remote temperature sensors are — · 20K Ohm: C7041B2005, C7041B2013, C7041C2003, C7041P2004, C7770A1006, C7772A1004, and C7772A1012
· 10K Ohm (for averaging only): TR21-A
· PS20 (535-34AB08-203) remote pipe sensor (20K Ohm)
· W6380B1005 fan coil unit relay control center · WSK-24 – wireless occupancy solution (receiver,
occupancy sensor and door sensor)
Models, applications, and features: Table 2 identifies the applications and features of
each model.

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TB6575/TB8575 SUITEPROTM DIGITAL FAN COIL THERMOSTATS

Table 2. Applications and Features

Models TB6575A1000 TB6575B1000
TB6575C1000 TB8575A1000

Applications

Heat/ Cool/ Auto

Pipes

All

2 or 4

Heat or Cool

2

All

2 or 4

All

2 or 4

Number Voltage of Relaysa

120 Vac or 240 Vac

5

120 Vac or 240 Vac

4

120 Vac/ 240 Vac/ 5 277 Vac

24 Vac

5

Energy Savings Input
Yes

Features
Fan: On, Manual/ Auto, or Auto 3 speed Changeover

Remote Sensor

Yes

Back Light

Pipe Sensorb

Yes

a The five relays are wired via terminals W, Y, Gh, Gm, and Gl. Relay 1 controls Heat open (W) or Cool open (Y). Relay 2 controls Cool open or Electrical heater output (Y/A). Relays 3, 4, and 5 control the High, Medium, and Low fan speeds respectively (Gh, Gm, and Gl). NOTE: In 2-pipe configurations without Auxiliary Heat, only 4 relays are used; relay 2 (Y/A) is not used.
b Pipe sensor is required for 2 pipe auto changeover and 2 pipe auxiliary heat applications.

5-13/16 (148)

3. Installer must be a trained and experienced ser-

1-1/8

vice technician.

(29)

3-13/16 (97)

THERMOSTAT SUB-BASE

3-1/4 (83)

1-3/16 (30)

5/32 (4)

5/32

UP

(4)

1-3/4 (44)

2-3/8 (60)

M27589

Fig. 1. Dimensions in inches (mm).

INSTALLATION

When Installing this Product…
1. Read these instructions carefully. Failure to follow them could damage the product or cause a hazardous condition.
2. Check the ratings given in the instructions and on the product to make sure the product is suitable for your application.

WARNING
Risk of electrical shock. Can cause severe injury, property damage or death. Disconnect power supply before installation and before servicing.
IMPORTANT The thermostats are line voltage powered devices. All wiring must comply with national and local electrical codes, ordinances and regulations. Provide disconnect means and overload protection, as required.
The TB8575A1000 thermostat must be powered by an approved 24 Vac, Class 2, NEMA rated transformer (such as a W6380 relay control center).
Location
The thermostats are the temperature control element in a fan coil or air- conditioning system. They must be located about 1.5m (5 ft.) above the floor, in a position with good air circulation, to sense room temperature.
IMPORTANT Do not mount the device where it can be affected by: 1. Drafts or dead spots behind doors or in corners. 2. Hot or cold air from ducts. 3. Radiant heat from the sun or appliances. 4. Unheated (uncooled) areas such as an outside wall behind the thermostat. 5. Concealed pipes or chimneys.

3

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TB6575/TB8575 SUITEPROTM DIGITAL FAN COIL THERMOSTATS

Mounting and Wiring
CAUTION
Equipment damage hazard. Operation at low temperatures can cause fan coil damage. This thermostat is not a safety device. Do not use it where the space temperature is outside of the device operating range.
A display of two dashes, , for the Room Temp display indicates a sensor failure or a temperature outside of the thermostat operating range of 18°C to 49°C (0°F to 120°F). With displayed, the thermostat ceases to operate. When the temperature returns to within its operating limits, the thermostat returns to operation.
The optional freeze protect feature should be used if low temperatures can occur.
The thermostat must be mounted flush to the wall. The thermostat can be mounted directly to a 2 in. (50.8 mm) x 4 in. (101.6 mm) horizontal junction box (see Fig. 2 on page 4). An optional adaptor plate (50033847-001) can be used with a 4 x 4 in. or a vertical junction box, for which mounting screws are supplied (see Fig. 3 on page 5).
1. Prepare the supply wires: a. Mounting on a 4 in. (101.6 mm) x 4 in. (101.6 mm) or vertical 2 in. (50.8 mm) x 4 in. (101.6 mm) junction box: (1) Feed the supply wires through the junction box and the opening in the adaptor plate. (2) Affix the adaptor plate to the junction box using the screws provided. b. Mounting on a horizontal 2 in. (50.8 mm) x 4 in. (101.6 mm) junction box: Feed the supply wires through the opening of the junction box.

2. Attach the supply wires: a. For the TB6575A1000, TB6575B1000 and TB6575C1000 models: (1) Push the fly lead wires through the wiring access hole in the sub-base. (2) Attach the fly lead wires to the supply wires using wire nuts (not provided). See Table 3 on page 6 for terminal and lead identification. (3) Push the fly lead and supply wires back into the junction box. b. For the TB8575A1000 model (which does not have pre-wired fly leads): (1) Attach the supply wires directly to the terminals on the sub-base. See Table 3 on page 6 for terminal identification. (2) Push the supply wires back into the junction box.
3. Mount the sub-base: a. Mounting on a 4 in. (101.6 mm) x 4 in. (101.6 mm) or vertical 2 in. (50.8 mm) x 4 in. (101.6 mm) junction box: ·Align the two holes at the top edges of the sub-base with the two pins on the adaptor plate. ·Attach the sub-base to the adaptor plate using the screws provided. b. Mounting on a horizontal 2 in. (50.8 mm) x 4 in. (101.6 mm) junction box: Attach the sub-base to the junction box using the screws provided.
4. Thoroughly check the wiring to the sub-base before finally mounting the thermostat on the wall.
5. Center the thermostat body over the sub-base, and press down firmly to engage the four tabs on the sub-base and snap the thermostat body into place.
6. Use the provided safety screw to secure the thermostat main body to the sub-base.
7. If using the adaptor plate, press the adaptor plate screw cover into place.

SUBBASE
MOUNT SUBBASE TO HORIZONTAL 2X4 JUNCTION BOX USING TWO SCREWS

SNAP MAIN BODY ONTO SUBBASE

INSERT SCREW TO LOCK MAIN BODY TO SUBBASE

M27590

Fig. 2. Mounting sub-base and thermostat to 2 in. (50.8 mm) x 4 in. (101.6 mm) junction box.

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4

ADAPTOR PLATE

TB6575/TB8575 SUITEPROTM DIGITAL FAN COIL THERMOSTATS
MOUNT ADAPTOR PLATE ONTO 4X4 WIRING BOX OR 2X4 VERTICAL JUNCTION BOX USING TWO SCREWS
SUB-BASE MOUNT SUB-BASE ONTO WALL PLATE USING TWO SCREWS

ADAPTOR PLATE
SCREW HEAD COVER

SNAP MAIN BODY ONTO SUB-BASE

INSERT SCREW TO LOCK MAIN BODY TO SUB-BASE

NOTE: MIDDLE HOLES OF ADAPTOR PLATE ARE USED FOR MOUNTING TO A 2X4 VERTICAL JUNCTION BOX. USE OUTER HOLES FOR MOUNTING TO A 4X4 WIRING BOX.

M27591

Fig. 3. Mounting sub-base and thermostat using the adaptor plate (50033847-001).

Terminal Wiring
Table 3 provides the terminal wiring for each model and application.

NOTE:

The TB6575A1000, TB6575B1000 and TB6575C1000 models have color coded fly leads attached to the terminals. Refer to Table 3 for the color codes.

The Terminal identifiers in Table 3 have the following meaning: · C: Common 24 Vac · Gh: High speed fan relay · Gl: Low speed fan relay

· Gm: Medium speed fan relay · L: Line voltage power (120 Vac/240 Vac/277 Vac) · N: Line voltage ground (120 Vac/240 Vac/277 Vac) · Ps: Pipe sensor (optional) · R: 24 Vac power · Rs: Remote sensor (optional) · SB: Remote setback (optional) · Sc: Ground (required if remote sensor, pipe sensor,
and/or remote setback are connected) · W/Y: W = Heating; Y = Cooling (2 pipe only) · Y/A: Y = Cooling; A = Electrical heater output

5

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TB6575/TB8575 SUITEPROTM DIGITAL FAN COIL THERMOSTATS

Table 3. Terminal Wiring.

Model

Application

1

TB6575A1000 — 120 Vac/240 Vac TB6575C1000 — 120 Vac/240 Vac/277 Vac

Terminal Identifier

L

Fly lead wire color

Black

2 pipes; Heat only

f

2 pipes; Cool only

2 pipes; Heat or Cool with Manual Changeover

2 pipes; Heat or Cool with Seasonal Changeover

4 pipes; Heat and Cool with Manual Changeover

4 pipes; Heat and Cool with Auto Changeover

2 pipes; Heat or Cool with Auxiliary Heat

4 pipes; Heat and Cool with Manual Changeover or Auto Changeover

TB6575B1000 — 120 Vac/240 Vac

Terminal Identifier

L

Fly lead wire color

Black

2 pipes; Heat only

2 pipes; Cool only

2 pipes; Heat or Cool with Manual Changeover

2 pipes; Heat or Cool with Seasonal Changeover

TB8575A1000 — 24 Vac

Terminal Identifierj

R

2 pipes; Heat only

2 pipes; Cool only

2 pipes; Heat or Cool with Manual Changeover

2 pipes; Heat or Cool with Seasonal Changeover

4 pipes; Heat and Cool with Manual Changeover

4 pipes; Heat and Cool with Auto Changeover

2 pipes; Heat or Cool with Auxiliary Heat

4 pipes; Heat and Cool with Manual Changeover or Auto Changeover

2
W/Y Orange W Y W/Y W/Y W W W/Y W
W/Y Orange W Y W/Y W/Y
W/Y W Y W/Y W/Y W W W/Y W

3 Y/A Yellow
Y Y A Y n/ai
Y/A
Y Y A Y

Terminals 45 6
Gl Gm Gh Red Blue Brown
Gl Gm Gh Red Blue Brown
Gl Gm Gh

7 8 9 10 11

N

Rsa Scb SBc Psd

White Nonee

Og Rh O

ORO ORO ORO ORO ORO ORO

ORO

N

Rsa Scb SBc Psd

White Nonee

ORO

C

Rsa Scb SBc Psd

ORO

a Rs; Remote sensor is optional. b Required when Rs, SB, or Ps is wired. c SB; Remote setback is optional. d Pipe sensor: Discrete, Analog, or Aquastat®. e These terminals (8, 9, 10, and 11) do not have lead wires attached to them. f A check mark () indicates the terminal is used in that application. Rs and SB terminal connections are
optional. If a terminal is left blank, it is not used in that application. g O = Optional h R = Required if Rs, SB, or Ps is wired. i Terminal 3 is not used on the TB6575B1000 model. j The TB8575A1000 model does not have fly lead wires attached to any terminals.

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TB6575/TB8575 SUITEPROTM DIGITAL FAN COIL THERMOSTATS

Accessory Wiring
Remote Pipe Sensor Wiring
The remote pipe sensor is used for 2 pipes auto and 2 pipes heat and cool with auxiliary heat changeover. The pipe sensor will sense the temperature in the pipes to tell the thermostat when the system is set to Heat or Cool.
1. Check Installer Setup number (IS) 5 to ensure it is set to the desired value. (See Table 4 on page 12).
2. Wire pipe sensor to Sc and Ps terminals. 3. Attach pipe sensor to bottom side of the pipe
with the leads pointing down. 4. Insulate pipe sensor, as necessary. 5. Change pipe sensor thresholds for cooling or
heating by setting Installer Setup Numbers (IS) 6 and 7 to desired values.
Remote Temperature Sensor Wiring
The TR21 is an optional remote temperature sensor that can be used as an alternative to the internal sensor. In addition to the TR21, other Resideo sensors that use a 20k Ohm curve may be used as the remote sensor.

1. Check Installer Setup Number (IS) 4 to ensure it is set to use the remote sensor. (See Table 4 on page 12).
2. Wire sensor to Rs and Sc thermostat terminals. 3. Push excess wire back into the hole. Plug the
hole using non-hardening caulk, putty or insulation to prevent drafts from affecting performance. 4. Remove sensor cover. 5. Mount sensor to the wall or junction box using the screws and anchors provided. 6. Level the sensor for appearance only. Device functions correctly even when not level. 7. Replace sensor cover.

NOTE: For complete wiring instructions, please follow the installation instructions provided with the remote sensor.

Sensor Wiring for Temperature Averaging
Fig. 4Fig. 6 illustrate sensor wiring for temperature averaging applications.

SUBBASE

Rs

Sc

WARNING
Risk of electrical shock. Can cause severe injury, property damage or death. Disconnect power supply before servicing.
CAUTION
Erratic system operation hazard. Failure to follow proper wiring practices can introduce disruptive electrical interference (noise). Keep wiring at least one foot away from large inductive loads such as motors line starters, lighting ballasts, and large power distribution panels. Shielded cable is required in installations where these guidelines cannot be met. Ground shield only to grounded controller case.

TR21

T

TR21

T

M27559
Fig. 4. Wiring four TR21 (20K ohm) sensors.

SUBBASE

Rs

Sc

IMPORTANT All wiring must comply with local electrical codes and ordinances or as specified on installation wiring diagrams.
— Wall module wiring can be sized from 16 to 22 AWG (1.31 to 0.33 sq. mm) depending on the application.
— The maximum length of wire from the thermostat to a wall module is 1000 ft. (305 m).
— Twisted pair wire is recommended for wire runs longer than 100 ft. (30.5 m).

T4

T3

T4

T3

1 TR21-A

1 THE TR21-A IS A 10K OHM SENSOR. M27560

Fig. 5. Wiring two TR21-A (10K ohm) sensors to provide a temperature averaging network.

7

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TB6575/TB8575 SUITEPROTM DIGITAL FAN COIL THERMOSTATS

SUBBASE

Rs

Sc

TR21

T

T4

T3

TR21

T

1 TR21-A

1 THE TR21-A IS A 10K OHM SENSOR.

M27561

Fig. 6. Wiring two TR21 (20K ohm) sensors and one TR21-A (10K ohm) sensor to provide a temperature averaging network.

Thermostat Wiring Diagrams
The figures in this section illustrate typical wiring for: · TB6575A1000, TB6575B1000 and TB6575C1000
fan coil thermostats, which are 120 Vac/240 Vac/277 Vac powered. Refer to Fig. 7Fig. 13, beginning on page 8, · TB8575A1000 model, which is 24 Vac powered. Refer to Fig. 14Fig. 20, beginning on page 9.

120/240/277 Vac Wiring Diagrams (TB6575A/B/C)

L

L (HOT)

W/Y

HEAT VALVE

Y/A

GI

Gm

FAN

Gh

N

Rs

REMOTE SENSOR

Sc

SB

REMOTE SETBACK

Ps M27566

Fig. 7. Two pipes Heat-only wiring diagram (120 Vac/240 Vac/277 Vac shown).

L

L (HOT)

W/Y

VALVE

Y/A

GI

Gm

FAN

Gh

N

Rs

REMOTE SENSOR

Sc

SB

REMOTE SETBACK

Ps M27568

Fig. 9. Two pipes (Heat or Cool) Manual Changeover wiring diagram (120 Vac/240 Vac/277 Vac shown).

L

L (HOT)

W/Y

VALVE

Y/A

GI

Gm

FAN

Gh

N

Rs

REMOTE SENSOR

Sc

SB

REMOTE SETBACK

Ps

PIPE SENSOR

M27569

Fig. 10. Two pipes (Heat or Cool) Auto Changeover wiring diagram (120 Vac/240 Vac/277 Vac shown).

L

L (HOT)

W/Y

HEAT VALVE

Y/A

COOL VALVE

GI

Gm

FAN

Gh

N

Rs

REMOTE SENSOR

Sc

SB

REMOTE SETBACK

Ps M27570

Fig. 11. Four pipes (Heat and Cool) Manual/Auto changeover wiring diagram (120 Vac/240 Vac/277
Vac shown).

L

L (HOT)

W/Y

COOL VALVE

Y/A

GI

Gm

FAN

Gh

N

Rs

REMOTE SENSOR

Sc

SB

REMOTE SETBACK

Ps M27567

Fig. 8. Two pipes Cool-only wiring diagram (120 Vac/240 Vac/277 Vac shown).

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TB6575/TB8575 SUITEPROTM DIGITAL FAN COIL THERMOSTATS

L

L (HOT)

W/Y

VALVE

Y/A

AUX

GI

Gm

FAN

Gh

N

Rs

REMOTE SENSOR

Sc

SB

REMOTE SETBACK

PIPE SENSOR Ps

M27571

Fig. 12. Two pipes (Heat or Cool) with Auxiliary Heat and Manual Changeover wiring diagram (120 Vac/240 Vac/277 Vac shown).

.

L W/Y Y/A
GI 1 Gm
Gh 2
N Rs Sc SB Ps

HEAT VALVE COOL VALVE

L (HOT)

5

FAN

3

REMOTE SENSOR REMOTE SETBACK

N4

1 REMOVE PRE-WIRED WIRE FROM TERMINAL 5 (MID FAN SPEED).

2 JUMPER TERMINALS 5 AND 6 (MID AND HIGH FAN SPEEDS). FAN MEDIUM SETTING WILL OPERATE ON HIGH SPEED.

3 CONNECT TERMINAL 7 TO THE MID FAN SPEED WIRE FROM THE PREVIOUS SYSTEM.

4 REWIRE THE PREVIOUS MID SPEED FAN WIRE TO THE NEUTRAL CIRCUIT IN THE SYSTEM.

5 CHANGE INSTALLER SETUP IS CODE 9 TO 2 FOR 2 SPEED FAN

CONTROL.

M31328A

Fig. 13. Wiring diagram when missing a wire for electromechanical retrofit
(120 Vac/240 Vac/277 Vac shown).

24 Vac Wiring Diagrams (TB8575)
For the TB8575A1000 model, a 24 Vac Class 2 NEMA rated transformer must be used.

R

W/Y

HEAT VALVE

Y/A

GI

Gm

FAN

L1

Gh

24 VAC

(HOT)

C

L2 1

Rs

REMOTE SENSOR

Sc

SB

REMOTE SETBACK

Ps

R

W/Y

COOL VALVE

Y/A

GI

Gm

FAN

L1

Gh

24 VAC

(HOT)

C

L2 1

Rs

REMOTE SENSOR

Sc

SB

REMOTE SETBACK

Ps

1 POWER SUPPLY. PROVIDE DISCONNECT MEANS AND

OVERLOAD PROTECTION AS REQUIRED.

M27574

Fig. 15. Two pipes Cool-only wiring diagram (24 Vac shown).

R

W/Y

VALVE

Y/A

GI

Gm

FAN

L1

Gh

24 VAC

(HOT)

C

L2 1

Rs

REMOTE SENSOR

Sc

SB

REMOTE SETBACK

Ps

1 POWER SUPPLY. PROVIDE DISCONNECT MEANS AND

OVERLOAD PROTECTION AS REQUIRED.

M27575

Fig. 16. Two pipes (Heat or Cool) Manual Changeover wiring diagram (24 Vac shown).

R

W/Y

VALVE

Y/A

GI

Gm

FAN

L1

Gh

24 VAC

(HOT)

C

L2 1

Rs

REMOTE SENSOR

Sc

SB

REMOTE SETBACK

Ps

PIPE SENSOR

1 POWER SUPPLY. PROVIDE DISCONNECT MEANS AND

OVERLOAD PROTECTION AS REQUIRED.

M27576

Fig. 17. Two pipes (Heat or Cool) auto changeover wiring diagram (24 Vac shown).

1 POWER SUPPLY. PROVIDE DISCONNECT MEANS AND

OVERLOAD PROTECTION AS REQUIRED.

M27573

Fig. 14. Two pipes Heat-only wiring diagram (24 Vac shown).

9

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TB6575/TB8575 SUITEPROTM DIGITAL FAN COIL THERMOSTATS

R

W/Y

HEAT VALVE

Y/A

COOL VALVE

GI

Gm

FAN

L1

Gh

24 VAC

(HOT)

C

L2 1

Rs

REMOTE SENSOR

Sc

SB

REMOTE SETBACK

Ps

1 POWER SUPPLY. PROVIDE DISCONNECT MEANS AND

OVERLOAD PROTECTION AS REQUIRED.

M27577

Fig. 18. Four pipes (Heat and Cool) Manual/Auto Changeover wiring diagram (24 Vac shown).

R

W/Y

VALVE

Y/A

AUX

GI

Gm

FAN

Gh

24 VAC

L1 (HOT)

C

L2 1

Rs

REMOTE SENSOR

Sc

SB

REMOTE SETBACK

Ps

PIPE SENSOR

Removing the Thermostat
WARNING
Risk of electrical shock. Can cause severe injury, property damage or death. Disconnect power supply before servicing.
CAUTION
Equipment damage hazard. Improper removal can damage the thermostat. Carefully follow the thermostat removal directions.
If it is necessary to remove the thermostat from the sub-base, refer to Fig. 21 and perform the following steps:
1. Turn off the thermostat by pressing the system button until OFF displays.
2. Remove the power source from the thermostat. 3. Remove the small safety screw at the bottom of
the thermostat. 4. Use both hands to pull the thermostat straight
away from the sub-base.

1 POWER SUPPLY. PROVIDE DISCONNECT MEANS AND

OVERLOAD PROTECTION AS REQUIRED.

M27578

Fig. 19. Two pipes (Heat or Cool) with Auxiliary Heat and Manual Changeover wiring diagram (24 Vac shown).

.

L W/Y Y/A
GI 1 Gm
Gh 2
C Rs Sc SB Ps

HEAT VALVE COOL VALVE

6

FAN

3

24 VAC

4 REMOTE SENSOR REMOTE SETBACK

L1 5 (HOT)
L2

1 REMOVE PRE-WIRED WIRE FROM TERMINAL 5 (MID FAN SPEED).

2 JUMPER TERMINALS 5 AND 6 (MID AND HIGH FAN SPEEDS). FAN MEDIUM SETTING WILL OPERATE ON HIGH SPEED.

3 CONNECT TERMINAL 7 TO THE MID FAN SPEED WIRE FROM PREVIOUS SYSTEM.

4 REWIRE THE PREVIOUS MID FAN SPEED WIRE TO THE NEUTRAL CIRCUIT IN THE SYSTEM.

5 POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.

6 CHANGE INSTALLER SETUP IS CODE 9 TO 2 FOR 2 SPEED FAN

CONTROL.

M31329A

Fig. 20. Wiring diagram when missing a wire for electromechanical retrofit (24 Vac shown).

M27592
Fig. 21. Removing the thermostat.
SETUP
The thermostat provides an LCD display, two buttons below the display for System and Fan control and two adjustment buttons (Up and Down) to the right of the display. See Fig. 23.
Settings, including setpoints, are permanently retained in EEPROM in case of a power outage.
Fig. 22 illustrates all the possible LCD display elements. Only those elements pertinent to the current settings and status (including the text for the two buttons, System and Fan), actually display.

62-0278–17

10

TB6575/TB8575 SUITEPROTM DIGITAL FAN COIL THERMOSTATS

Locked

Freeze Set to Protect Setup

ºF ºC

Set to RoomTemp

Test

Pipe

ºF ºC

Sensor

Economy

Setback

Heat On Cool On OffHeatAutoCool

Fan On LowMedHiAuto
M27584

Fig. 22. LCD display with all possible elements shown.

UP AND DOWN ARROW BUTTONS

Set to

ºF

RoomTemp ºF

Heat On Heat

Fan On Auto

System Fan

SYSTEM BUTTON

FAN BUTTON

M27586

Fig. 23. LCD display showing default screen.

Power-up

At power-up, the thermostat’s LCD shows all display segments for two seconds, enters a self-test mode for a few seconds, and then displays the current room temperature (default screen), as shown in Fig. 23.

NOTE:

If there is a temperature sensor failure or the temperature is outside of the operating range, the room temperature display shows two dashes, — –. When the sensor returns to its operating range, the temperature display resumes.

CAUTION
Equipment damage hazard. Power overload will damage the thermostat. The thermostat has a safety fuse rated at 15 A/ 250 Vac. If the fuse blows, the thermostat must be replaced. The fuse is not field replaceable.
This fuse is provided as a safety feature to prevent fire if the thermostat is overloaded.
Installer Setup (IS) Mode
To enter Installer Setup Mode: · Press and hold both the System button (labeled
Heat/Cool) and the Up Arrow button for three (3) seconds. This displays the setup screen on the LCD. See Fig. 24.
NOTE: Exiting Installer Setup Mode is the same as the method for entering setup mode.
Table 4 provides the setup codes (IS codes) and values. To enter the setup parameters:
1. Press the System (Heat/Cool) button to cycle through the IS codes, which display in the upper right following the word Setup.
2. Press the Up or Down Arrow buttons to cycle through the option values for the currently displayed IS code. The values display in the center of the screen.
3. After the desired value displays, press the System button to store your value selection and display the next IS code.
Setup
M27585
Fig. 24. Installer Setup (IS) mode screen.

11

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TB6575/TB8575 SUITEPROTM DIGITAL FAN COIL THERMOSTATS

Table 4. Installer Setup (IS) Codes and Options.

IS Code 1
2

Code Description Line Voltage Selection
System Type

Option Value 0 1 2 0 1 2 3

4

5

6

7

2.5 Fan On/Off Selection 0

for Aux Heat On

1

3

Valve Output Type 0

1

4

Sensor Type

0

1

5

Pipe Sensor

0

1

2

3

4

6

Pipe Sensor

50 to 72

Threshold for Cooling

7

Pipe Sensor

75 to 90

Threshold for Heating

8

Temperature Scale 0

1

8.5 Fan Speed at motor 0 start up

1

9

Number of Fan

1

Speeds

2

3

Option Description (Default value shown in Bold)

Notes

120 Vac power supply (Default)

240 Vac power supply

277 Vac power supply

Heat only

Cool only

Two pipes: Heat or Cool; Manual Changeover

Two pipes: Heat or Cool; Seasonal Changeover (requires optional pipe sensor)

Four pipes: Manual Changeover

TB6575A, TB6575C and TB8575A only

Four pipes: Auto Changeover

TB6575A, TB6575C and TB8575A only

Two pipes: Heat or Cool; with Auxiliary Heat (requires optional pipe sensor).

Allows auxiliary heat to turn on when pipes have cold water (TB6575A, TB6575C and TB8575A only).

Four pipes: Manual and Auto Changeover (Default)

TB6575A, TB6575C and TB8575A only

Fan ON when Auxiliary Heat is on (Default) Fan OFF when Auxiliary Heat is on

Enables or disables the auto fan operation when Auxiliary Heat is On (TB6575A, TB6575C and TB8575A only).

N.C. (normally closed) – ON/OFF (Default)

N.O. (normally open) – ON/OFF

Onboard Sensor (Default)

Remote Sensor (TR21 or other 20K Ohm sensor)

Default mode is Heat: N.O. (normally open) Input. Only displays when system type 3 or 6 is selected.
Default mode is Cool: N.O. (normally open) Input. Only displays when system type 3 or 6 is selected.
Default mode is Heat: N.C. (normally closed) Input. Only displays when system type 3 or 6 is selected.
Default mode is Cool: N.C. (normally closed) Input. Only displays when system type 3 or 6 is selected.

The Pipe Sensor code automatically displays based on the System Type (IS code

2) selection. For example, only when you select the value 3 or 6 for the

System Type, will the Pipe Sensor code and its values display. Pipe sensor will flash on display screen if analog input (#4) is lost. Pipe sensor status and water temperature can be checked in test mode (see “Installer Test (IT) Mode” on page 15 for details)

Analog input (Default). NTC20K, whose curve is the same as TR21. Only displays when system type 3 or 6 is selected.

Range is 50°F to 72°F. Default is 60°F.

Changes to Cool when pipe temperature is below threshold.

Range is 75°F to 90°F. Default is 80°F.

Changes to Heat when pipe sensor temperature is above threshold.

Degrees Fahrenheit (°F); Default.

Degrees Celsius (°C).

Provide full power when fan motor starts always starts in High speed start up ensures that there

high fan speed (Default)

is enough torque to start the motor and

eliminates and motor locking.

Disable fan will start at speed that is needed as defined by VersaSpeed

Single Speed Fan

Low speed only

2 Speed Fan

Hi and Low speed fans only

3 Speed Fan (Default)

Hi, Med, and Low speed fan

62-0278–17

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TB6575/TB8575 SUITEPROTM DIGITAL FAN COIL THERMOSTATS

Table 4. Installer Setup (IS) Codes and Options. (Continued)

IS

Option

Code Code Description Value

9.5 Fan Control Type 0

1

10 Control Method for 4- 1 Pipe Auto Changeover

2

10.5 Deadband for

2 to 9

Heat/Cool Setpoints

Switching Differential 2 to 6 for Single Setpoint

11 CPH Value for Heat 1 to 12

12 CPH Value for Cool 1 to 6

13 CPH for Auxiliary 1 to 12 Electrical Heater

14 Display Temperature -4 to 4 Adjustment

15 Temperature Display 0

Mode

1

2

16 Setpoint Range Stop 50 to 90 for Heating

17 Setpoint Range Stop 50 to 90 for Cooling

18 Keypad Lockout 0

1

2

3

19 Remote Setback 0 1

2

3

4

5

Option Description (Default value shown in Bold)

Notes

Constant and Auto (Default) Auto only

When fan is in Auto, the fan ramping algorithm, Veraspeed, is used

Single Setpoint (Default)

Uses switching differential to change between heating and cooling and controls to a single setpoint (Only displayed for system types 5 or 7)

Heat and Cool Setpoints (2 setpoint method)

Uses a deadband of no control and controls to a heat or cool setpoint. (Only displayed for system types 5 or 7)

Range is 2 to 9. Default is 3. Deadband = minimum distance Available when Heat and Cool

between heating and cooling setpoints.

Setpoints are chosen for the control

method for 4-pipe Auto (IS 10)

Range is 2 to 6. Default is 3. Heat switching point = setpoint Available when Single Setpoint is

– switching differential. Cool switching point = setpoint + chosen for the control method for 4-

switching differential.

pipe Auto (IS 10)

Range is 1 to 12. Default is 4.

The number selected indicates the maximum times Heating is cycled on per hour (CPH).

Range is 1 to 6. Default is 3.

The number selected indicates the maximum times Cooling is cycled on per hour (CPH).

Range is 1 to 12. Default is 6.

The number selected indicates the maximum times Auxiliary Heating is cycled on per hour (CPH).

Range is -4°F to +4°F; Default is 0°F.

Display Room Temperature Display Setpoint Display Temperature and Setpoint; Default. Range is 50°F to 90°F. Default is 90°F.

Range is 50°F to 90°F. Default is 50°F.

All keys are available (Default)
The System button (Heat/Cool) is locked out
Both the System and Fan buttons are locked out.
All buttons are locked out (System, Fan, Up Arrow, and Down Arrow). The LCD displays LOCKED.
Disabled
Hotel card enabled N.O. for unoccupied mode with 1 second software delay going from UnOccupied to Occupied; 2 minute delay going from Occupied to UnOccupied.
Hotel Card enabled N.C. for unoccupied mode with 1 second software delay going from UnOccupied to Occupied; 2 minute delay going from Occupied to UnOccupied.
Hotel Card enabled N.O. for unoccupied mode with 1 second software delay going from UnOccupied to Occupied; 30 minute delay going from Occupied to UnOccupied
Hotel Card enabled N.C. for unoccupied mode with 1 second software delay going from UnOccupied to Occupied; 30 minute delay going from Occupied to UnOccupied.
Button Press (Default)

Press and hold “Heat/Cool/Off” button for 3 seconds and thermostat will go into “Economy Setback”

13

62-0278–17

TB6575/TB8575 SUITEPROTM DIGITAL FAN COIL THERMOSTATS

Table 4. Installer Setup (IS) Codes and Options. (Continued)

IS

Option

Code Code Description Value

Option Description (Default value shown in Bold)

Notes

20 Remote Setback for 50 to 70 Range is 50°F to 70°F. Default is 64°F. Heating

Used when the thermostat is in the Unoccupied state.

21 Remote Setback for 72 to 90 Range is 72°F to 90°F. Default is 79°F. Cooling

22 Activity Sensing

0

1

2

3

Disabled (Default) 4 hour sensing 8 hour sensing 12 hour sensing

This will be selectable when IS 19 is set to option 0 or 5. If IS 19 is configured for N.O or N.C, activity sensing will not be available.

4

16 hour sensing

5

20 hour sensing

6

24 hour sensing

23 Freeze Protection 0 1

Disabled
Enabled (Default) Stat cycles On Heat when room temperature reaches 40°F (4°C), and disables Heat when room temperature reaches below 46°F (8°C). The LCD displays FREEZE PROTECT

This feature can not activate when the application is Cool only.

24 Auto Fan Reset

0

1

Inactive (Default)
Resets back to Auto after 2 hours. The start time is calculated after the initial call for Heat/Cool is satisfied. Then, the two (2) hour timing begins.

Auto Fan Reset is not allowed (does not display) when the fan control type is set to Auto Only, (IS 9 – value 1).

2

Resets back to Auto after 4 hours. The start time is

calculated after the initial call for Heat/Cool is satisfied.

Then, the four (4) hour timing begins.

25 Purge Cycle

0

No periodic purge (other purges still apply)

Frequency

1

Purge every 2 hours (Default)

2

Purge every 24 hours

Option 1 Default is normally recommended to make sure changeover is detected quickly on spring and fall days.

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TB6575/TB8575 SUITEPROTM DIGITAL FAN COIL THERMOSTATS

Installer Test (IT) Mode
To enter Installer Test Mode: · Press and hold both the Up arrow button and the
Down Arrow button for three (3) seconds. This displays all segments of the LCD screen on the LCD. See Fig. 22 on page 11. Table 5 provides the Test codes (IT codes) and values. To enter the IT codes:
1. Press the System (Heat/Cool) button to cycle through the IT codes, which display in the upper right above the word Test.
2. Press the Up or Down Arrow buttons to cycle through the values for the currently displayed IT code. The values display in the center of the screen.
3. After the desired value displays, press the System button to store your value selection and display the next IT code.
NOTE: Exiting Installer Test Mode is the same as the method for entering test mode,
Test
M27587
Fig. 25. Installer Test (IT) mode screen.

Table 5. Installer Test (IT) Codes and Options.

IT

Code

Option

Code Description

Value

Option Description

10 Heat Control

0

Close

1

Open

20 Auxiliary Heat

0

Control

1

Close Open

30 Cool Control

0

Close

1

Open

40 Fan Control

0

Close

1

Low Speed

2

Medium Speed

3

High Speed

50 Pipe Sensor

32-199

Displays the pipe sensor temperature. Only used for System Type 3 or 6 (IS 2, value 3 or 6). Only the Analog pipe sensor is tested.

71 Software Main version

01-99 A 2-digit number, 01-99

72 Software Vice version

01-99 A 2-digit number, 01-99

73 Configuration Data 01-99 A 2-digit number, 01-99 Main version

74 Configuration Data 01-99 A 2-digit number, 01-99 Vice version

75 Week Produced 01-52 A 2-digit number, 01-52

76 Year Produced 08-99 A 2-digit number, 08-99

OPERATION

PROPORTIONAL + INTEGRAL (P+I) CONTROL

Like a mechanical thermostat, the fan coil thermostats have On/Off control output. However, this output is regulated by a P+I algorithm, enabling the thermostat to control closer to setpoint than conventional thermostats. This results in performance where the space temperature is maintained within 0.75°C (1.5°F) of the setpoint regardless of fan speed.

NOTE:

Integral action corrects the temperature control errors of proportional-only control, but it is slower to react to large temperature or setpoint changes.

Economy Setback Modes

ACTIVITY SENSING (IS CODE #22) If Activity Sensing is enabled, any time the thermostat is not touched (no single key is pressed) for the duration selected, the thermostat automatically falls back into the Economy Setback. The LCD displays ECONOMY SETBACK just to the right of the main temperature display to indicate Activity Sensing mode is active. When any key is pressed, the thermostat controls to Occupied mode.

BUTTON PRESS SETBACK (IS CODE #19-5) The default remote setback option is for economy setback via a button press on the thermostat. In this mode, the thermostat can quickly be setback by pressing and holding down the System Mode button for more than 3 seconds. The LCD displays ECONOMY SETBACK just to the right of the main temperature display to indicate the Setback is active. When any key is pressed, the thermostat controls to Occupied mode.
REMOTE SETBACK (IS CODE #19) Remote Setback is activated by a dry contact closure on the remote setback input from an occupancy sensor, time switch, or hotel card key. The thermostat controls to the user/installer defined setback setpoints for increased energy savings. The LCD displays Economy Setback just to the right of the main temperature display to indicate the Remote Setback mode is active.
When Remote Setback is active, all buttons on the thermostat are disabled. However, the button combinations to access Installer Setup (IS) and Installer Test (IT) remain enabled.
ECONOMY SETBACK OPERATION For Heat Mode, when Economy Setback is enabled, the set point changes to the remote setback heating setpoint (IS CODE #20).

15

62-0278–17

TB6575/TB8575 SUITEPROTM DIGITAL FAN COIL THERMOSTATS

For Cool Mode, when Economy Setback is enabled, the set point changes to the remote setback cooling setpoint (IS CODE #21).
For 4 pipe applications with Auto Changeover and Heat/Cool Setpoints, when Economy Setback is enabled, the cool setpoint changes to the remote setback cooling setpoint and the heat setpoint changes to the remote setback heating setpoint. The new effective deadband is the difference between the remote setback heating setpoint and the remote setback cooling setpoint.
Fig. 26 illustrates the relationship between setpoints, Remote Setback, and deadband for auto changeover with heat and cool setpoints.

UNOCCUPIED DEADBAND

REMOTE SETBACK COOL SETPOINT COOL SETPOINT

DEADBAND

UNOCCUPIED DEADBAND

HEAT SETPOINT
REMOTE SETBACK HEAT SETPOINT M27562

Fig. 26. Auto Changeover with Heat/Cool Setpoints deadband illustration.

For 4 pipe applications with Auto Changeover and a single setpoint, when Economy Setback is enabled, the setpoint will revert to a dual heat/cool setpoint approach. The remote setback heating and remote setback cooling setpoints will be used to create an effective unoccupied deadband.

Fig. 27 illustrates the unoccupied deadband when Economy Setback is enabled for 4-pipe single setpoint auto changeover.

REMOTE SETBACK COOL SETPOINT

UNOCCUPIED DEADBAND

COOL SWITCHING POINT SETPOINT

HEAT SWITCHING POINT UNOCCUPIED DEADBAND

REMOTE SETBACK HEAT SETPOINT
M31331
Fig. 27. 4 Pipe Auto Changeover with Single Setpoint and Economy Setback Deadband
Illustration

Fan Modes

VERSASPEEDTM FAN RAMPING When the fan switch is in auto, the thermostat will cycle the fan using the fan ramping algorithm. The appropriate fan speed is selected according to Fig. 28.

The fan ramping algorithm is illustrated in Fig. 28

+4°F

DIFFERENCE BETWEEN

+2°F

RT AND

SETPOINT -2°F

-4°F

FAN SPEED IS HIGH
FAN SPEED IS MEDIUM FAN SPEED IS LOW FAN SPEED IS LOW
FAN SPEED IS MEDIUM
FAN SPEED IS HIGH

COOL SETPOINT
HEAT

M27563

Fig. 28. VersaSpeedTM fan ramping algorithm illustration.

AUTO FAN RESET (IS CODE #24) If Auto Fan Reset is enabled, and a constant fan speed is selected, the thermostat resets the fan to Auto. · Value = 1: The fan resets back to Auto after 2 hours. · Value = 2: The fan resets back to Auto after 4 hours. The start time is calculated after the initial call for Heat/Cool is satisfied. Then, the two or four hour timing begins. The fan is set back to Auto when the 2hour or 4-hour delay expires.

Application Modes

2 PIPE SEASONAL CHANGEOVER APPLICATIONS These applications require the pipe sensor as a N.O, N.C., or Analog Input to detect seasonal changeover: · 2 pipes with auto changeover · 2 pipes with auxiliary heat

Changeover occurs when the system has been changed over from the boiler to the chiller. This occurs on a seasonal basis from winter to summer months. When using a pipe sensor as an analog input, the thermostat can use the logic below to determine what mode to operate in. A changeover will occur when the pipe temperature goes above the threshold for heating or below the threshold for cooling. If a purge has not occurred or a call has not been satisfied in awhile, the pipe temperature may start to get close to the ambient temperature. In this case, the thermostat will only changeover once the temperature falls into the opposite threshold.
2 Pipes with Auto Changeover For this application the system switch only provides “Off” and “Auto”. When in “Auto” mode the water temperature will indicate if the thermostat should operate in heating or cooling.
Operation: After exiting the installer setup, the thermostat will perform a 5 minute purge. During this initial 5 minute purge, the valve (W/Y) will energize and the fan will be de-energized. After the 5 minute purge, the thermostat will go into the appropriate mode as described in Table 6.

62-0278–17

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TB6575/TB8575 SUITEPROTM DIGITAL FAN COIL THERMOSTATS

Table 6. Logic for 2 Pipes with Auto Changeover

Pipe Temperature after purge System Mode

Threshold for Heating (IS code #7) Heat

Between Thresholds After Purge Occurs

Fan Only*

< Threshold for Cooling (IS code #6) Cool

*If pipe temperature is between the two threshold values after the 5 minute purge occurs, the thermostat will activate a second 5 minute purge to double check the water temperature. If after the second 5 minute purge, the water temperature is still between the two thresholds, the valve output will be disabled and only manual fan will be available. It will stay in this operation until the next purge cycle occurs.

2 Pipes with Auxiliary Heat For this application, when there is hot water in the pipes, the system switch provides “Off” and “Heat”. When there is cold water in the pipes, the system switch provides “Off”, “Heat”, and “Cool”.

Operation: After exiting the installer setup, the thermostat will perform a 5 minute purge. During this time, the valve (W/Y) will energize and the fan and auxiliary heat (Y/A) will be de-energized. After the 5 minute purge, the thermostat will go into the appropriate mode as described by Table 7.

Table 7. Logic for 2 Pipes with Auxiliary Heat

Pipe Temperature After Purge

Heat Mode

Cool Mode

Threshold Valve (W/Y)

Changeover.

for Heating energized on calls Mode changes to

(IS code #7) for heat

Heat.

Between Thresholds After Purge Occurs

Aux Heat (Y/A) energized on calls for heat

Changeover. Mode changes to Heat because Cool is not available.

< Threshold for Cooling (IS code #6)

Mode stays in Heat Valve (W/Y) but Aux Heat (Y/A) energized on calls energized on calls for cool for heat

If pipe temperature is between the two threshold values after the 5 minute purge occurs, the thermostat will activate a second 5 minute purge to double check the water temperature. If after the second 5 minute purge, the water temperature is still between the two thresholds, the valve output will be disabled and only auxiliary heat will be available for heating.
Auxiliary heat (Y/A) always de-energizes during purges.
Purge Cycles for 2 Pipe Seasonal Changeover Applications For 2 Pipe with Auto Changeover and 2 Pipe with Auxiliary Heat applications, the thermostat will run purge cycles to determine if there is hot or cold water in the pipes.

A 5 minute purge will occur every 2 or 24 hours (IS 25) to ensure that the pipe sensor is sensing the correct mode during seasonal changeover months.
A 5 minute purge will also occur anytime the installer setup or installer test menus are exited, whenever the thermostat is switched from its “Off” position1, and if the power is reset.
1 For the 2 Pipe with Auxiliary Heat application, the thermostat must be in the “Off” position for more than 30 minutes before a 5 minute purge will occur when it is switched back into “Heat” or “Cool”.
4 PIPES AUTO CHANGEOVER
Single Set Point Method In 4 pipe auto changeover with a single setpoint, the temperature is always controlled to the setpoint. Switching points are used to determine when to switch between heating and cooling modes. If the current mode is heat and the temperature drifts above the cool switch point (Setpoint

Switching Differential), the thermostat will switch to heat operation and will heat the space until setpoint is reached.
For this application, the setpoint setting and switching points are illustrated in Fig. 29. The switching differential is defined via IS code #10.

SWITCHING DIFFERENTIAL

COOL SWITCHING POINT SETPOINT HEAT SWITCHING POINT

M31330
Fig. 29. 4 Pipe Auto Changeover with Single Setpoint and Switching Points
Heat/Cool Setpoint Method In 4 pipe auto changeover with heat and cool setpoints, the system key is used to switch between the heating setpoint and cooling setpoints. Use the Up and Down arrow buttons to change the setpoint.
For this application, the setpoint settings and deadband are illustrated in Fig. 30. The deadband is changed via IS code #10.

COOLING SETPOINT

DEADBAND

HEATING SETPOINT M27565

Fig. 30. 4 Pipe Auto Changeover setpoints and deadband.

17

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TB6575/TB8575 SUITEPROTM DIGITAL FAN COIL THERMOSTATS
TROUBLESHOOTING
Table 8 provides troubleshooting information.

Table 8. Troubleshooting.

Symptom

Possible Cause

Action

Display does not come on.

Thermostat is not being For TB6575A/B/C, check for 120 Vac/240 Vac/277 Vac

powered.

between L and N.

For TB8575A, check for 24 Vac between R and C.

Temperature settings do not change.

The upper or lower

Check the temperature setpoints for heating and cooling

temperature limits were (Installer Setup codes 16 and 17 respectively). Modify as

reached.

needed.

The keypad is fully locked.

Change keypad locked options (Installer Setup code #18).

Heating or cooling does not come on.

System Type selection Set the Installer Setup code #2 (System Type) to the correct not set to Heat or Cool or value to match the installed heating and/or cooling the selection is incorrect. equipment. Verify operation of wiring and equipment in
Installer Test mode.

Thermostat is calling Heating or cooling for Heat (Heat on) or equipment is not Cool (Cool on) but no operating. heating or cooling is running.

Check wiring. Check that the Installer Setup code #2 (System Type) value matches the installed heating and/or cooling equipment. Verify operation of equipment in Installer Test mode.

Heat does not turn Heating equipment on (Heat On is solid failure. in the display).

For TB6575A/B/C: 1. Check for 120 Vac/240 Vac/277 Vac at the equipment between power and common, (terminals L and N). 2. Check for 120 Vac/240 Vac/277 Vac between the heat (W) and common (N) terminals. If 120 Vac/240 Vac/277 Vac is present, the thermostat is functional.

For TB8575A: 1. Check for 24 Vac at the equipment on the secondary side of the transformer between power and common (terminals R and C). 2. Check for 24 Vac between the heat terminal (W) and transformer common. If 24 Vac is present, the thermostat is functional.

If voltage is present, check the heating equipment to find the cause of the problem.

Loose connection or broken wire between thermostat and heating equipment.

For TB6575A/B/C: Check for 120 Vac/240 Vac/277 Vac between the heat (W) and common (N) terminals.
For TB8575A: Check for 24 Vac between the heat terminal (W) and transformer common.

Both the heating and Incorrect System Type

cooling equipment selected.

are running at the same time.

Heating and cooling wires are shorted

together.

If voltage is not present, check wire connection (loose or broken) between the thermostat and the heating equipment.
Check that the Installer Setup code #2 (System Type) value matches the installed heating and/or cooling equipment.
Separate the shorted heating and cooling wires.

62-0278–17

18

TB6575/TB8575 SUITEPROTM DIGITAL FAN COIL THERMOSTATS

Table 8. Troubleshooting. (Continued)

Symptom
Cooling does not turn on (Cool On is solid in the display).

Possible Cause
Cooling equipment failure.

Action
For TB6575A/B/C: 1. Check for 120 Vac/240 Vac/277 Vac at the equipment between power and common, (terminals L and N). 2. Check for 120 Vac/240 Vac/277 Vac between the cool (Y) and common (N) terminals. If 120 Vac/240 Vac/277 Vac is present, the thermostat is functional.
For TB8575A: 1. Check for 24 Vac at the equipment on the secondary side of the transformer between power and common (terminals R and C). 2. Check for 24 Vac between the cool terminal (Y) and transformer common. If 24 Vac is present, the thermostat is functional.

Loose connection or broken wire between thermostat and cooling equipment.

If voltage is present, check the cooling equipment to find the cause of the problem.
For TB6575A/B/C: Check for 120 Vac/240 Vac/277 Vac between the cool (Y) and common (N) terminals.
For TB8575A: Check for 24 Vac between the cool terminal (Y) and transformer common.

If voltage is not present, check the wire connection (loose or broken) between the thermostat and the cooling equipment.

Fan does not turn on Wiring or connection in a call for Heat. failure

Check wiring and make sure the connection is correct.

Cannot select fan speed.

Fan Control Type selection is incorrect.

Check that the Installer Setup code #9 (Fan Control) value is set to zero (0).

Heating equipment Incorrect System Type

is running in the

configured.

Cool mode.

Check that the Installer Setup code #2 (System Type) value matches the installed heating and/or cooling equipment.

Heating equipment Incorrect System Type does not turn off and configured. heat temperature setting is set below room temperature (Heat On is not in the display).

Check that the Installer Setup code #2 (System Type) value matches the installed heating and/or cooling equipment.

Cannot set the system setting to Heat.

System Type (Installer Set the Installer Setup code #2 value to match the installed Setup code #2) is set to heating and/or cooling equipment. Cool Only (value = 1).

Cannot set the system setting to Cool.

System Type (Installer Set the Installer Setup code #2 value to match the installed Setup code #2) is set to heating and/or cooling equipment. Heat Only (value = 0).

Heat On is not in the System Type setting is Set the Installer Setup code #2 to Heat and set the

display.

not set to Heat and/or temperature setting above the room temperature.

the temperature setting

is not set above the room

temperature.

Cool On is not in the System Type setting is Set the Installer Setup code #2 to Cool and set the temperature

display.

not set to Cool and/or setting below the room temperature.

the temperature setting

is not set below the room

temperature.

Remote sensor does Incorrect IS code.

not display temperatures

Sensor is not compatible.

Set the Installer Setup code #4 to Remote (value = 1). The remote sensor must be TR21 or compatible 20K NTC.

Remote Setback does not activate

Incorrect IS code.

Make sure the NO/NC and timer selection is correct. Check the value selected for IS code #19.

Remote setpoint error. Make sure the remote setback setpoint is correct for energy saving usage.

19

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TB6575/TB8575 SUITEPROTM DIGITAL FAN COIL THERMOSTATS

Table 8. Troubleshooting. (Continued)

Symptom

Possible Cause

Activity Sensing does not exit when button pressed

All buttons are locked.

Freeze Protection does not activate

System Type is set to Cool.

System mode is not Off.

Auto Fan Reset does Incorrect IS code.

not activate

Calling for Heat/Cool

setpoint couldn’t be

satisfied.

Action Make sure keypad lockout is disabled. Set IS code #18, value = 0.
Freeze protection is not activated when system type is Cool (IS code #2; value = 1). Change System Type. Set the System mode button to Off. Set the Installer Setup code #24 to Enabled (value = 1 or 2). Only after the setpoint is satisfied, will the auto fan reset timer activate.

LIMITED TWO-YEAR WARRANTY

Resideo warrants this product, excluding battery, to be free from defects in workmanship or materials, under normal use and service, for a period of two (2) years from the date of first purchase by the original purchaser. If at any time during the warranty period the product is determined to be defective due to workmanship or materials, Resideo shall repair or replace it (at Resideo’s option).
If the product is defective,
(i) return it, with a bill of sale or other dated proof of purchase, to the place from which you purchased it; or
(ii) call Resideo Customer Care at 1-800-468-1502. Customer Care will make the determination whether the product should be returned to the following address: Resideo Return Goods, 1985 Douglas Dr. N., Golden Valley, MN 55422, or whether a replacement product can be sent to you.
This warranty does not cover removal or reinstallation costs. This warranty shall not apply if it is shown by Resideo that the defect was caused by damage which occurred while the product was in the possession of a consumer.
Resideo’s sole responsibility shall be to repair or replace the product within the terms stated above. RESIDEO SHALL NOT BE LIABLE FOR ANY LOSS OR DAMAGE OF ANY KIND, INCLUDING ANY INCIDENTAL OR CONSEQUENTIAL DAMAGES

RESULTING, DIRECTLY OR INDIRECTLY, FROM ANY BREACH OF ANY WARRANTY, EXPRESS OR IMPLIED, OR ANY OTHER FAILURE OF THIS PRODUCT.
Some states do not allow the exclusion or limitation of incidental or consequential damages, so this limitation may not apply to you.
THIS WARRANTY IS THE ONLY EXPRESS WARRANTY RESIDEO MAKES ON THIS PRODUCT. THE DURATION OF ANY IMPLIED WARRANTIES, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, IS HEREBY LIMITED TO THE TWO YEAR DURATION OF THIS WARRANTY. Some states do not allow limitations on how long an implied warranty lasts, so the above limitation may not apply to you.
This warranty gives you specific legal rights, and you may have other rights which vary from state to state. If you have any questions concerning this warranty, please write Resideo Customer Care, 1985 Douglas Dr, Golden Valley, MN 55422 or call 1-800-468-1502.
CUSTOMER ASSISTANCE
If you have any questions about the operation of your thermostat, please go to customer.resideo.com

Resideo Inc., 1985 Douglas Drive North, Golden Valley, MN 55422
www.resideo.com 62-0278–17 M.S. Rev. 12-19 | Printed in United States
This product is manufactured by Resideo Technologies, Inc., Golden Valley, MN, 1-800-468-1502 ©2019 Resideo Technologies, Inc. The Honeywell Home trademark is used under license from Honeywell International Inc. All rights reserved.