Hydrolevel 711 Series Low Water Cut Off Feeder Combination For Steam Boilers Owner’s Manual
- June 13, 2024
- HYDROLEVEL
Table of Contents
- 711 Series Low Water Cut Off Feeder Combination For Steam Boilers
- HOW TO INSTALL
- PRINCIPLE OF OPERATION
- INSTALLATION & OPERATION OF FEEDER:
- OPERATING INSTRUCTIONS
- TROUBLESHOOTING
- SERVICE / MAINTENANCE
- DIMENSIONS
- SPECIFICATIONS
- OPTIONS
- LIMITED MANUFACTURER’S WARRANTY
- References
- Read User Manual Online (PDF format)
- Download This Manual (PDF format)
711 Series
Low Water Cut-Off Feeder Combination for Steam Boilers
120 VAC Operating Voltage
711 Series Low Water Cut Off Feeder Combination For Steam Boilers
No moving parts in water.
No floats to hang-up or foul.
Unique two probe design.
Bouncing water line won’t cause on-off burner cycling or water valve slamming
noise.
Easy installation. Quick hook-up fittings adapt control to all 8″ to 14″ sight
glasses.
Simple fast wiring. Can be used with any standard automatic water feeder.
WARNING
Read and understand these instructions completely before installing or
servicing this control.
Save these instructions for future reference.
Disconnect power supply before beginning installation to prevent
electrical shock or equipment damage.
Only qualified personnel may install or service the control in
accordance with local codes and ordinances.
This low water cut-off must be installed in series with all other limit
and operating controls installed on the boiler. After installation, check for
proper operation of all of the limit and operating controls, before leaving
the site.
We recommend that secondary (redundant) Low Water Cut-Off controls be
installed on all steam boilers with heat input greater than 300,000 BTU/hour
or operating above 15 psi of steam pressure.
At least two controls should be connected in series with the burner control
circuit to provide safety redundancy protection should the boiler experience a
low water condition. Moreover, at each annual outage, the low water cut-offs
should be dismantled, inspected, cleaned, and checked for proper performance.
To prevent serious personal injury from steam and hot water make sure
there is a discharge line from the blow down valve to a proper place of
disposal.
To prevent a fire, do not use this low water cut-off to switch currents
over 7.4A, 1/3 Hp at 120 VAC or 3.7A, 1/3 Hp at 240 VAC, unless a starter or
relay is used in conjunction with it.
** Previous controls should never be installed on a new system. Always
install new controls on a new boiler or system. Failure to follow this warning
could cause property damage, personal injury or death.
CAUTION** A more frequent replacement interval may be necessary based on
the condition of the unit at time of inspection. Hydrolevel’s warranty is two
(2) years from the date of manufacture.
HOW TO INSTALL
MODEL 711 COMES WITH:
➀ (2) 6″ x 1/2″ brass nipples
➁ (1) 1/2″ x 1/2″ x 3/8″ tee
➂ (1) 1/2″ x 1/2″ x 1/2″ tee
➃ (1) 2″ x 1/2″ brass nipple
➄ (1) 711C manifold casting
➅ (1) 3/8″ copper tube
➆ (2) 3/8″ compression fittings
➇ (1) 3/4″ nipple
➈ (1) Blow down valve
NOTE: Discharge line not included.
Remove gauge glass assembly and nipples replacing nipples with two 6″ brass nipples provided ➀. Install 1/2″ x 1/2″ x 3/8″ tee ➁ on top nipple.
Install 1/2″ x 2″ brass nipple ➃ and 1/2″ x 1/2″ x 1/2″ tee ➂ to 1/2″ threaded
hole in casting ➄.
NOTE: Casting is designed for either left or right mounting on gauge
glass. Be sure to plug hole on opposite side.
Thread tee attached to casting into bottom 6″ nipple. Tighten until casting is vertical.
Install compression fittings ➆ into casting and top tee. Size copper tubing ➅ and tighten between the two compression fittings.
Attach control to probes using No. 8-32 self tapping screws provided. Install nipple and blow down valve (with discharge line) in bottom 3/4″ tapped hole.
Reattach gauge glass cocks and gauge glass into end of 1/2″ tees. Pressure- trol can be threaded into 1/8″ threaded hole on top of casting. If pressure- trol is not used, plug 1/8″ hole on top of casting.
Attach blue probe lead wire to upper probe and white probe lead wire to bottom probe with wing nuts and lock washers provided.
WIRING METHOD A:
Same 120V Power Source for Control and Burner Circuit
A1 Connect input voltage (120 VAC, 60HZ) to terminals 2 and 1. 120 VAC, 60HZ must be supplied to terminals 2 and 1 for internal operation of the control.
A2 Install a jumper between terminal 1 and terminal P1. Power from terminal P1 is supplied to terminal P2 when water reaches the upper probe. Power to terminal P2 is removed when water falls below the bottom probe.
A3 Connect terminal 2 to burner circuit neutral. Connect terminal P2 to
burner circuit in series with other limit controls. Consult boiler
manufacturer’s instructions for proper terminal connections.
NOTE: Control is wired in series with and before other limits.
A4 Feeder Connection: Connect feeder common to terminal 2. Connect feeder hot to terminal A. Whenever water falls below the lower probe, power is supplied to the feeder terminal A. When water reaches the upper probe, power to the feeder is removed.
WIRING METHOD B:
For use with Gas Boilers or Separate Power Source for Control and Burner
Circuit
B1 Connect input voltage (120 VAC, 60HZ) to terminals 2 and 1. 120 VAC, 60HZ must be supplied to terminals 2 and 1 for internal operation of the control.
B2 Connect hot lead from burner control circuit to terminal P1.
This terminal supplies power to terminal P2 in normal operating conditions
when water is at the probe. Connect neutral to burner circuit.
NOTE: Consult boiler manufacturer’s instructions for proper terminal
connections.
B3 Connect terminal P2 to burner circuit in series with other limit
controls.
Consult boiler manufacturer’s instructions for proper terminal connections.
NOTE: Control is wired in series with and before other limits.
B4 Feeder Connection: Connect feeder common to terminal 2. Connect feeder
hot to terminal A. Whenever water falls below the lower probe, power is
supplied to the feeder terminal A. When water reaches the upper probe, power
to the feeder is removed.
NOTE: All schematic diagrams show all systems in the off position. No
power applied.
PRINCIPLE OF OPERATION
Hydrolevel controls are electronically operated.
Water is used as an electrical conductor to complete a circuit from the probe
to the control unit.
The control unit provides switching contacts to operate the burner circuit and
optional water feeder.
The 711 Series low water cut-off is designed to maintain a safe operating
water level in the boiler. When water is in contact with the upper probe, the
control enables the burner to fire (switch contacts P1 – P2 are closed).
When the water level falls below the lower probe, the control will de-energize
the burner circuit.
The control will not re-energize the burner until the water level is restored
to the upper probe level.
The 711WF includes a feed valve designed to automatically restore the water
level in the event of a low water condition. When water falls below the lower
probe, the 711 will energize the feed valve (switch contact 1 – A make). When
the boil er water level is restored to the upper probe, the 711 will
deenergize the feed valve and restore burner
operation. The 711CF does not include a feed valve, but does provide contacts
for operation of a steam boiler water feeder.
NOTE: 711CF is only compatiable with a 120V Feeder
See page 6 for information on the VXT Water Feeder.
INSTALLATION & OPERATION OF FEEDER:
For WF Models ONLY
A feed valve is supplied standard with control model 711WF. It is
recommended that a shut-off valve and union be installed on either side of the
water feed valve and a bypass valve and piping be installed to permit removal
of the water feed valve should service be required.
During normal operation, by-pass valve should be closed and isolation valves
should remain open.
Feed Valve Maintenance (WF Models Only)
WARNING Water Damage Potential: Failure to maintain the feed valve can
result in excess mineral deposits collecting in the valve. If left unchecked,
these deposits can impede valve operation with the potential for overfilling
the heating system and allowing water to escape radiators into the living
space.
The following maintenance must be performed by a qualified service
technician:
Annually
• Remove and clean the strainer located on the valve body. IMPORTANT: If the
strainer shows signs of mineral deposits collecting on the screen, install a
Hydrolevel Feed Valve Service Kit (Part No. 45-715).
Every 3 Years
Install Hydrolevel Feed Valve Service Kit (Part No. 45-345). Note: If hardened
calcium deposits have formed on the brass surface inside the valve, replace
the valve (Part no. 45-343).
12 Years
Replace the Feed Valve Assembly after 12 years of service.
OPERATING INSTRUCTIONS
NOTE: Hydrolevel recommends that the boiler manufacturer’s procedures for skimming the boiler be performed prior to placing the control into operation.
- After installation, raise the boiler water level until water is in contact with the upper probe. Turn on power and set the thermostat to call for heat. The burner should fire immediately.
- Using the boiler drain, slowly lower the water level to a point below the lower probe. The burner should shut down immediately upon a low water condition.
NOTE: The water should not be lowered beyond a visible point on the gauge glass.
IMPORTANT: If the burner does not shut down in a low water condition, turn off power immediately and refer to troubleshooting instructions below.
TROUBLESHOOTING
- If the burner does not shut down upon water falling below the lower probe: Remove power to the burner and check installation. Check wiring and make sure that burner is connected to the fourth terminal from left on terminal (P2). If wiring is correct, check to make sure the probes are not falsely grounded. Voltage between the probes and chassis ground should be 120-140 VAC with water beneath both probes. A lower reading may indicate a shorted probe. Remove probes and check for contamination.
- If the burner will not fire with water at the top probe: With a voltmeter and power applied at terminals G and H: Check the voltage between the upper probe and chassis ground. Reading should be 0-10 VAC with water at the upper probe. A higher reading may be the result of poorly conductive water or probe contamination. Remove probes and check for contamination. If the burner will still not fire after cleaning probes, contact factory for assistance.
SERVICE / MAINTENANCE
REGULAR MAINTENANCE REQUIRED. Failure to properly maintain the control can
lead to severe damage to the boiler, other property, personal injury, or
death.
To prevent serious personal injury from steam and hot water, make sure there
is a discharge line from the blowdown valve to a proper place of disposal.
Failure to follow this caution could result in personal injury.
The 711 Series Control requires regular maintenance to ensure continued, safe
operation. During normal boiler function, sediment may accumulate in the low
water cutoff’s probe housing.
If left unchecked, this sediment can build up, trap water in the probe
housing, and prevent the control from detecting a low water condition in the
boiler.
A regular blow down of the control is required for proper operation.
To flush the sediment from the chamber, the control must be blown down
throughout the heating season in accordance with the following schedule:
- Daily for first week following control installation
- Prior to heating season startup in the fall
- Once per week during the heating season
Instructions: Confirm water is visible in the gauge glass. If not
visible, shut the burner off, allow the boiler to fully cool, then add water
until visible in the gauge glass. Once water is visible, bring your boiler
back up to temperature. With the boiler running, place a heat resistant pail
directly beneath the control casting blow down valve.
Open the valve and allow the sediment and water to drain into the pail.
Continue to drain the water until it runs clean (One to two gallons is
generally sufficient).
Close the valve when completed. Replenish the water in the boiler if needed.
DIMENSIONS
SPECIFICATIONS
| MAXIMUM PRESSURE: | 15 PSI |
|---|---|
| INPUT VOLTAGE: | 120 VAC, 60 HZ |
| SWITCH RATINGS: | 5.8 FLA, 34.8 LRA |
| SWITCH CONTACTS: | SPDT |
| ALARM CIRCUIT: | 125 VA @ 120 VAC Pilot Duty |
OPTIONS
The VXT water feeder (available separately) can be used with Hydrolevel or
other low water cut-offs to automatically replenish boiler water in the event
of a low water condition.
The VXT offers programmable feed amount and feed delay settings. These can
easily be set to ensure the proper feed amount and to provide adequate time
for condensate to return to the boiler before starting a feed cycle. The VXT’s
digital feed counter tracks the amount of water added to the boiler exposing
system leaks, which can significantly shorten the life of a cast iron boiler.
Additional features including a manual feed button underfeed and flood
protection, make the VXT an ideal choice for safety and convenience.
WARNING Frozen pipes/water damage. Central heating systems are prone to shut down as a result of power or fuel outages, safety related fault conditions or equipment failure. Installation of freeze protection monitoring or other precautions is recommended for unattended dwellings in climates subject to sustained below-freezing temperatures.
LIMITED MANUFACTURER’S WARRANTY
We warrant products manufactured by Hydrolevel Company to be free from defects
in material and workmanship for a period of two years from the date of
manufacture or one year from the date of installation, whichever occurs first.
In the event of any claim under this warranty or otherwise with respect to our
products which is made within such period, we will, at our option, repair or
replace such products or refund the purchase price paid to us by you for such
products. In no event shall Hydrolevel Company be liable for any other loss or
damage, whether direct, indirect, incidental or consequential. This warranty
is your EXCLUSIVE remedy and shall be IN PLACE OF any other warranty or
guarantee, express or implied, including, without limitation, any warranty of
MERCHANTABILITY or fitness for a particular purpose.
This warranty may not be assigned or transferred and any unauthorized transfer
or assignment thereof shall be void and of no force or effect.
126 Bailey Road, North Haven, CT 06473
• Phone 203-776-0473 • FAX
203-764-1711 •
www.hydrolevel.com