Bard ECON-NC2 Wall Mount Air Conditioners and Heat Pumps Installation Guide
- June 13, 2024
- Bard
Table of Contents
INSTALLATION INSTRUCTIONS
Full Flow Low Leakage Economizer with
Exhaust for Building Applications
(To Be Used with Field-Installed DCV Controls)
Models:
ECON-NC2 & ECON-NC3
(Factory-Installed Vent Option)
For Use with 1-1/2 Through 3 Ton
Wall Mount Air Conditioners and Heat Pumps
NOTE: These instructions are written to cover field-installed economizers,
but are also
included with factory-installed economizers. For factory-installed
economizers,
all portions addressing “installation” are for reference only.
Economizer Features
- One piece construction—easy to install. Directdrive actuator eliminates linkage.
- Exhaust air damper—built in with positive closed position. Provides exhaust air capability to prevent pressurization of tight buildings.
- Actuator Motor – 24 volt, power-open, springreturn, direct-coupled with stall protection. Selfcentering shaft clamp and access cover facilitate ease of replacement/maintenance.
- 10K outdoor temperature sensor
GENERAL
Economizer with Exhaust Model Nomenclature
General Information
The economizer should only be installed by a trained heating and air
conditioning technician. These instructions serve as a guide to the technician
installing an economizer package, not as a step-by-step procedure with which
the mechanically inclined owner can install the package.
The economizer housing is shipped in one carton, which contains the electrical
harness, miscellaneous hardware and installation instructions.
Any wall mount unit equipped with an economizer must also have a factory/field
installed low ambient control.
Please refer to appropriate model/year Specification Sheet for requisite field
installed low ambient control kit part numbers.
Unpacking
Upon receipt of the equipment, be sure to compare the , model number found
on the shipping label with the accessory identification information on the
orders and shipping document to verify that the correct accessory has been
shipped.
Inspect the carton housing of each economizer assembly as it is received and,
before signing the freight bill, verify that all items have been received and
there is no visible damage. Note any shortages or damage on all copies of the
freight bill. The receiving party must contact the last carrier immediately,
preferably in writing, requesting inspection by the carrier’s agent. Concealed
damage not discovered until after loading must be reported to the carrier
within 15 days of its receipt.
Description
ECON-NC economizers are designed to be used with the wall mount series air
conditioners and heat pumps, shown in Table 1, equipped with low ambient
controls and field-installed controller. They are electromechanical economizer
systems designed to provide “free” cooling where the outdoor air temperature
is cool enough to provide the needed cooling without running the compressor,
or in addition to the compressor. When cooling is required, the system
automatically takes advantage of cold outdoor air when available and uses it
for first stage cooling.
This then reduces the need to run the air conditioning compressor providing
lower operating costs and increasing the service life of the equipment. If the
outdoor air temperature is too warm to be sufficient for cooling, the dry bulb
outdoor air temperature sensor detects the condition and should automatically
close the outdoor air intake/exhaust damper, open the return air damper and
switch to compressor-only operation.
ECON-NC Series economizers are not for use with variable capacity ECU models.
TABLE 1
Economizer Application
Model (1)| | |
---|---|---|---
ECON-NC2| W18A
W24A| W18H
W24H| W18L
W24L
ECON-NC3| W30A
W36A| W30H
W36H| W30L
W36L
- Low ambient control is required w/economizer for low temperature operation.
INSTALLATION OF FIELD-INSTALLED ECONOMIZER
Basic Installation
WARNING
Electrical shock hazard. Electrical shock can result in serious injury or
death. Disconnect remote electric power supply or supplies before servicing.
Preparing Unit for Economizer Installation
-
Disconnect power to unit.
-
Unpack the economizer assembly, which includes the integral economizer with attached electrical harness, mixed air sensor, body panels, miscellaneous hardware and installation instructions.
-
From existing wall mount unit, remove and save (or discard) as directed (see Figure 1):
• Blower access panel and screws (save)
• Ventilation access panel (discard)
• Filter access panel (discard)
• Filter (save)
• Outer and inner control panel doors and screws (save) -
Remove and discard the exhaust cover plate (save screws).
-
Install new condenser exhaust plate with screen over opening into condensor section (see Figure 2).
-
The unit includes a filter partition and tray assembly installed below the blower. The ventilator can be installed without moving this assembly, but it may be beneficial to loosen the front two (2) mounting screws of the filter partition assembly.
The assembly can then be lifted up slightly to allow more room for installation of the unit ventilator. -
Install the return fill plate using three (3) screws as shown in Figure 3 on page 6.
Outdoor Air Sensor Installation
-
Remove and save both side grilles and screws.
-
Install the outdoor temperature sensor in the lower condenser section on the same side as the control panel with two (2) screws provided as shown in Figure 4.
FIGURE 4
Outdoor Air Sensor Installation
-
Route the wire harness through the condenser base and into the control panel (see Figure 5). Secure with two wire ties (provided). Push harness up through the grommet in the bottom of the control panel. Secure with wire ties (provided) to the other wires in the grommet. Ensure the wire harness cannot contact moving parts or copper tubing. Replace side grilles.
Economizer Installation
-
Connect 12-pin male plug into female plug in side of the control panel as shown in Figure 6. See wiring diagram found on page 10.
-
Insert economizer into opening in wall unit between the filter tray and condenser section, being careful not to tear unit insulation. Fully seat economizer assembly to the rear of the wall unit cavity. Slide economizer to right and line up with return air opening in back of wall unit.
-
Re-install and tighten front filter tray mounting screws (if loosened in Step 6 on page 4).
-
Left hand units: Use the 52″ wire harness (provided). Plug the 12-pin male connector into the female plug in the control panel. Route the wire harness to the back of the economizer and attach to the return fill plate using the push-in wire ties provided (see Figure 7). Plug the male 12-pin connector from the economizer actuator into the wire harness.
Right hand units: Plug the 12-pin male connector straight into the female plug in the control panel. Plug the outdoor sensor wire connectors into the spade connectors on the 12-pin male plug (orange wires) as shown in Figure 8.
-
Remove front door, control door and mist eliminator from economizer hood assembly.
-
Lift economizer hood to unit and hold in position.
Line up four (4) holes in outer economizer hood door (two on each side) with corresponding holes in unit and mount economizer hood to unit with four (4) screws. -
Connect vent option front to vent hood door (see Figure 9) using ten (10) screws (supplied).
-
Re-insert filter into filter brackets. Arrow on filter should point up.
-
Install filter door.
-
Attach blower access panel.
Economizer Checkout
- Attach wall unit outer and indoor control panel doors.
- Turn power to unit on.
- After confirming economizer operation, attach the economizer hood mist eliminator (with airflow arrow pointed towards unit), control door and front door.
Control Wiring Connection Diagram
See economizer wiring diagram below. For low voltage connections, refer to the
wall-mount unit installation instructions manual.
Bard Manufacturing Company, Inc.
Bryan, Ohio 43506
www.bardhvac.com
Manual : 2100-797
Supersedes: NEW
Date: 7-13-23