Owner’s Manual
Quantum Energy Technologies
Document number: QDC0030PD-16.4 Page 29 of 36
4. Compressor runs hot:
Internal leakage.
High
suction
superheat.
High current draw.
High head pressure.
Thermal
Cut
Out
faulty.
De-ice solenoid
remains open.
Observe compressor operation: pressure
delivery, noise.
Check gas amount (gas leakage), check TX
valve settings (closed too much), or check
TX valve element (leakage).
Check for refrigerant over charge, TX valve
open too much, compressor winding
resistance or mechanical fault in the
compressor rotors or valves.
Check for high condensing temperature due
to: I) the thermostat sensor does not contact
the tank well, or II) faulty water thermostat
/ digital controller, which does not cut off
or III) restriction, blockage in condenser or
filter/drier or IV) poor heat transfer to tank
- possibly insulation material entered the
space between condenser coil and tank.
Check for correct operation of Digital
Controller.
Check for faulty de-ice solenoid parts or
thermostat. Check for incorrect wiring.
If faulty, replace the compressor.
Find out and fix the leaking
spot and charge the right amount
of gas. Open TX valve 1/4 each
step and have a observation.
Replace TX valve.
Adjust gas charge if needed.
Close TX valve if needed, or
replace compressor if it is faulty.
I). Make the sensor contact the
tank well. II) Replace faulty
water thermostat / digital
controller. III) If restriction is
not removable replace blocked
part. IV) Replace tank.
Replace Digital Controller if
faulty.
Replace faulty de-ice parts.
Correct wiring.
5. Poor oil return to
compressor.
Check for oil traps in the tubes between
evaporator and tank.
Rectify installation defects
A.
3: No Hot Water; Compressor Running
Probable Cause
Test / Observation
Action
1. Tank water drawn
off - unit only
recently started.
Wait until water is heated.
If water is not heated in the
expected time, check for other
reasons like short of gas.
2.
Low
or
no
refrigerant.
Check for shortage of refrigerant or leakage
in the system.
Refer to Table A.2: Item 1
3. Compressor not
compressing.
a. Check for internal valve leak. When shut
off, gas will go back through the
compressor making noise and vibration.
b. Minimum pressure difference across
compressor due to TX valve malfunction
(open too much). Test TX valve.
a. Replace compressor if faulty.
b. Adjust (close) or Replace
TX valve.
4. Frozen evaporator.
a. Malfunction of de-ice system or
persistent cold weather resulting in poor
performance of the fin coil evaporator.
b. Blocked evaporator.
c. Restricted airflow.
a. Repair or replace de-ice system
or avoid running in constant
cold weather.
b. Repair blockage or replace
parts.
c. Clean or replace air filter (if
fitted), or clear an blockages on
the air ways.
