The cold water supply must be
left in the open position when the water
heater is in use.
An alarm bell with silencing switch is available as
an option on this water heater. The alarm bell can
be used to provide an audible indication of a
control sensed malfunction. The user must
specify the safety function or multiple safety
functions that the alarm bell will sound on when
the water heater is ordered from the factory. The
alarm bell typically is used to indicate a low water
condition or a high water temperature condition.
The alarm is furnished with a silencing switch to
turn off the audible alarm while trouble shooting
a control sensed malfunction that is indicated by
an audible alarm. Once the control sensed
malfunction is corrected, the silencing switch
must be returned to the “ON” position to
re-establish the audible alarm function.
Never operate the heating elements without
being certain the water heater is filled with
water and a temperature and pressure relief
valve is installed in the relief valve opening on
top of the heater.
The pilot switch(es) (if equipped) mounted on the
control cabinet permit the heater to be turned on and off
without having to operate the electrical disconnect
switch. The pilot switch interrupts only the 120 VAC
control circuit in the water heater. Full power is still
present at the terminal block, fuses and contactors.
A relief valve that discharges periodically may be
due to thermal expansion in a closed system.
Many water systems are equipped with pressure
reducing valves, check valves or back flow
preventers which may cause the water system to
be closed. As water is heated it will expand in
volume due to thermal expansion. The system
must make allowance for this expansion. If an
expansion tank is not provided in the system,
water pressure may increase to the point where
the water heater’s temperature and pressure relief
valve opens to relieve the excess pressure. The
temperature and pressure relief valve is not
intended for the constant relief of thermal
expansion. This is an unacceptable condition and
must be corrected.
Do not plug or cap the relief
valve discharge!
A properly sized expansion
tank is typically installed in the potable water
system to relieve the pressure built up by thermal
expansion of heated water. Consult your local
plumbing contractor and plumbing wholesaler for
assistance in properly selecting an expansion tank
for your system.
As the water heater operates, there may be noises
generated by the expansion and contraction of the
metal parts of the water heater and related piping.
These noises may occur during periods of heat up
or cool down. They do not represent harmful or
dangerous conditions.
1. Insure that the electrical power to the water
heater is in the “OFF” position. If the power
disconnect point is out of sight, lock it in the
open (“OFF”) position and tag to prevent
unexpected application of power.
2. Close the water heater drain valve(s).
3. Open a nearby hot water faucet to allow the
air in the system to escape as the tank fills.
4. Fully open the cold water inlet valve to the
water heater to begin filling the heater and piping.
5. Check the nearby hot water faucet to verify
that air is exiting the tank as it fills with water.
Allow water to run until a constant flow is
obtained at the faucet. This will insure that all
air is purged from the system.
22
START-UP PROCEDURE
Full power is present whenever the cabinet
door is opened, even with the pilot
switch(es) turned off.
DANGER:
THERMAL EXPANSION OF WATER
FILLING THE WATER HEATER
NOTE:
