Specifications

88
• Troubleshooting must be performed by authorized dealer or qualified contractor.
Fault Causes/ Check Point
Unit cannot start 1. Power supply plug disconnected.
2. Circuit breaker or fuse tripped/ blown.
3. Wiring connection.
4. If fault persist, contact your installer.
Neither fan motor and
compressor run
1. The fuse may be blown or circuit breaker opened.
2. Check electrical circuit or motor winding for shorts or grounds.
3. Check wiring connections. Wire may be loosening. Replace or
tighten.
4. Control system may be faulty.
Compressor does not operate 1. Check capacitor if available. Replace capacitor if faulty.
2. Check wiring connection. Wire may be loosening. Replace or
tighten.
3. The high pressure switch may tripped due to:
a) No or insufficient water flows into and leaves heat exchanger.
May be clogged.
b) Water entering temperature higher than the maximum operating
conditions.
c) Not enough air flow into fan coil units. May be due to dirty filter
or block by object, cardboard and etc (heating mode).
d) Fan coil motor failure (heating mode).
e) Unit over-charged. Release some of the refrigerant charge.
4. The compressor internal/ external overload protection is
triggered. If the compressor body is extremely hot, the overload
will not reset until it cooled down.
5. The compressor winding may be grounded to the compressor
shell. If so, replace the compressor.
Insufficient cooling or
heating
1. Check handset for temperature setting.
2. Filter may be clogged. Check and clean the filter.
3. Check capillary tube for possible restriction of refrigerant flow.
Replace capillary tube if proven so.
4. The reversing valve may be defective (valve position is not
shifted properly), creating a bypass of refrigerant. Check the
reversing valve coil connection.
5. Check for restriction of air and water flow.
6. Refrigerant leakage. Check all piping bends and connection for
leakage. Repair the leakage area or replace with new piping.
7. Window or door wide open.
8. Unit may be under-sized.
Insufficient water flow
through heat exchanger
1. Valves are not opened fully.
2. Circulating water pump is faulty.
3. Water pipes or strainers are clogged.
Noisy operation 1. Check for loose bolts or screws.
2. Make sure rubber isolators are used for installation.
3. Check for water balance to units for proper water flow rate.
4. Check for tubing touching compressor or other surface. Readjust
tubing by bending it slightly.
5. Fan blower knocking/ hitting on its housing.
6. May be due to worn compressor bearing.
Troubleshooting