Operating instructions

64
Operation
Operation:
Troubleshooting guide
Troubleshooting guide.
Problem
number
Problem Possible cause Action
27
28
Fill valve does not
close (cont.).
Reduced or no output
(even though water
level is correct)
 Fill valve is stuck
 Heater
malfunctioning
 Malfunctioning
control system
 Check if fill valve is installed
backwards. If yes, repipe.
 If there is a faulty internal spring or
diaphragm in the fill valve, replace
valve.
 Check if there is an obstruction that
will not allow valve to seat properly.
Clean or replace valve as needed.
 Check for control voltage across fill
valve coil. (Check wiring and
controls.)
 Verify that proper voltage is being
applied to heaters.
 Check heater amperage.
 If heater contactor is not functioning,
replace.
 Check if heater fuses are blown and
replace if required.
 Check if auxiliary limit controls are
not allowing system to operate (i.e.,
duct humidistats, air flow proving
switch, etc.). Reset, replace or
calibrate as needed. (Air flow switch,
terminals 12 and 13, measures 24
VAC if open. On-off high limit,
terminals 25 and 26, measures 21
VDC if open.)
 Check if the (optional) heater over-
temperature thermostat has been
tripped. Reset if necessary.
 Replace zone valve if end switch is
not closing.
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