TC 120
682.98767.00 • 10/04/2018
42
Modulating valve is not
operating, but OUT2 LED is
on.
Set process temperature to
minimum and check for complete
travel of valve.
Insufficient pressure
differential between cooling
Water In and Out lines.
Find a means to get less back
pressure in the Water Out line.
Cooling valve is undersize.
Replace cooling valve with a
larger valve.
Unit does not
heat/cannot achieve
set point.
Defective heater contactor.
Visually inspect coil and contacts;
repair/replace defective contactors.
Defective immersion heater.
Check resistance on all three (3)
legs of the heater with an ohm
meter. If not all equal, contact
factory for replacement heater.
Controller heat output open.
Check the heater output with an
ohm meter to ground. It should
read in the mega-ohm range.
Infinite or zero readings indicate a
defective output.
Heater contactor is not
energizing, but HEAT LED is
on.
Set process temperature to
maximum and check for control
voltage at heater contactor.
Immersion heater elements
dirty.
Remove heater and clean
elements.
Immersion heater element is
burned out.
Check heater tank for
scorched/discolored paint. Check
resistance on all three (3) legs of
the heater with an ohm meter.
Replace heater as required.
Check for balanced amp draws,
and supply voltage. If not present
replace immersion heater.
OUT1 indicator is on, but no
voltage on heater contact.
Replace relay board on controller.
Cooling valve is leaking.
Dismantle valve and clean out.
Solenoid valve is not
operating, but COOL LED is
on.
Set process temperature to
minimum and check for
magnetism on top of solenoid coil.
Magnetism on coil.
Clean coil.
Faulty/dirty solenoid valve.
Press VENT button several times
to flush the valve.
Relief valve leaks.
Foreign material under valve
seat.
Manually open valve to clear seat
of material.
High system pressure.
Reduce WATER IN or MAKEUP
water pressure.
Unit runs
continuously
cooling or heating,
and cannot attain
set point.
Unit under-sized for
application.
Call sales representative.