INSTALLATION & OPERATION OF FEEDER
A feed valve is supplied standard with control
model 724WF. It is recommended that a shut-off
valve and union be installed on either side of the
water feed valve and a by-pass 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 iso-
lation valves should remain open.
PRINCIPLE OF OPERATION
Hydrolevel controls are electronically operated.
Water is used as an electrical conductor to com-
plete 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 724 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 724WF 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 724 will energize the feed
valve (switch contact 1 - A make). When the boiler
water level is restored to the upper probe, the 724
will de-energize the feed valve and restore burner
operation. The 724CF does not include a feed
valve, but does provide contacts for operation of a
steam boiler water feeder.
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. 45-725).
Every 3 Years
I
nstall 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. 45-725).
12 Years
Replace the Feed Valve Assembly after 12 years of service.
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.
Feed Valve Maintenance (WF Models Only)
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