20
TROUBLESHOOTING
MOST LIKELY PROBLEMS AND CAUSES
Important:
For system to operate properly power should be turned ON
and all shut-off valves/isolation valves must be open.
If Pump Does Not Run:
1.
Circuit board controls operation of pump.
Check that pump LED is illuminated.
Check for 24VAC at pump terminal on circuit board.
If faulty refer to “Faulty Circuit Board” section.
2.
Check line voltage wiring to pump. Check for 120 VAC at
pump relay and inside the pump electrical box.
Pump is Noisy:
Air may be trapped in the water circuit. Purge air from the system as
described under “start-up procedure”.
Insufficient or No Heat:
1.
Air may still be trapped in heating loop. Purge air from the
system as described under “start-up procedure”.
2.
Water heater thermostat not turned up high enough.
(Remember, higher than 120 °F = mixing valve for domestic
service).
3.
Inlet and outlet piping connection at the air handler may be
reversed. See “Hot Water Piping”).
4.
Water heater thermostat not calibrated properly.
5.
Excessive pressure drop caused by restriction somewhere in the
hot water loop does not allow sufficient water to flow to air
handler.
6.
Air handler not sized large enough for heat load.
7.
Water heater not large enough to satisfy heat load.
