6-28
I
Troubleshooting
Troubleshooting
Symptom
Possible Cause
Solution
Unable to cool properly.
Cooling water supply is not suf-
ficient.
Check to make sure the cool-
ing water supply is of sufficient
temperature, volume and pressure
for the unit.
Drain (cooling water return line)
is not sufficient.
Check the drain (cooling water
return line) to ensure there is no
restriction preventing water flow
to the drain (cooling water return
line).
Cooling valve is inoperative.
Check the drain (cooling water
return line) and see if you can feel
or hear a change in the flow as the
cooling valve open and closes. If
you cannot hear or feel the flow
it is likely the valve has failed.
Replace valve if necessary.
Plugged heat exchanger (only
on models with heat exchanger
option).
Clean or replace heat exchanger.
High backpressure in the cooling
water system
Reduce backpressure.
Heater failure.
Unit not filled with water.
Fill unit with water.
Faulty heater.
Replace heater.
Plugged heater tube / flow restric-
tion.
Clear obstruction.
Pressure relief valve leaks.
The combined pressure of the
incoming cooling water pres-
sure and the unit pump pressure
exceeds the pressure rating of the
pressure relief valve.
Install a pressure-reducing valve
on the incoming cooling water
line. Review the start-up proce-
dure for cooling water pressure
requirements at various operating
temperatures.
Pressure relief valve stuck in
open position.
Replace valve.
(Continued)
Replacing the Heater Contactor
WARNING: Electrical Shock Hazard
Only qualified service personnel who have been trained on electrical testing and
the procedures for avoiding the hazards should diagnose or correct problems that
require opening the unit with power on.
The heater contactors should be replaced if:
•
You have checked the continuity and found
that resistance across the coil equals zero
ohms or is an open circuit.
•
You have checked continuity of the power
legs (with the heater wires disconnected)
and find them continuously connected. Or,
you have checked continuity across the
power legs and find an open circuit even
when the coil is energized.
To replace the heater contactor:
1
Disconnect and lockout the main power.
2
Open the electrical enclosure door.
Turn the
screw on the front panel counterclockwise to open.
3
Disconnect wires from the heater contactor.
Make sure you label the wires to ensure you can
connect them correctly to the new contactor.
4
Remove the contactor
by removing the mounting
screws that hold it in place.
5
Reverse this procedure starting with step 4 to
install the new contactor.
Make sure the wires
are connected correctly.
IMPORTANT:
Always refer to the wiring
diagrams that came with your Thermolator
to locate specific electrical components.
Illustrations in the User Guide are intended to
be representative only.
Usual
Location
for
Heater
Contactor
Summary of Contents for Thermolator TW-P
Page 6: ...iv I Table of Contents ...
Page 12: ...1 6 I Introduction ...
Page 36: ...3 14 I ...
Page 58: ...4 22 I Operation ...
Page 72: ...5 14 I Maintenance ...
Page 128: ...E 4 I Appendix ...
Page 134: ...G 4 I Appendix ...
Page 136: ...H 2 I Appendix ...