1.3 Compressor trouble diagnosis
1.3.1 Electrical troubles
1) Ground test
Test single phase and three phase in the same
manner.
(1) Shut off the power supply to product.
(2) Remove the wires connected to the compres-
sor terminal.
(3) Clean the compressor terminal and discharge
(suction) pipe.
(4) Measure the resistance of discharge (suction)
pipe and each terminal by using a R x 1K
scale of Ohm meter.
(5) If dial moves remarkably, the terminal is in
ground state. So, replace the compressor.
2) Wrong wiring check of compressor terminal
Examine the wiring diagram of compressor terminal or the electric circuit diagram of product on the cover
of compressor terminal to check if there is wrong wiring.
3) Checking of wire disconnection or overload protector (O.L.P) operating condition
This check is to see the wire terminal condition of motor inside, and for a single phase compressor with
O.L.P built-in, it identifies the O.L.P operating condition and wire disconnection.
(1) Shut off the power supply to product.
(2) Remove the wires connected to the compres-
sor terminal.
(3) After checking the ground state, cool the
compressor sufficiently.
(at room temperature)
<For single-phase compressor>
(4) Measure the resistance of each terminal by
Ohm meter R x 1K scale, and if dial does not
move, compressor is in opened condition.
<For three-phase compressor>
(5) Measure the resistance of each terminal by
Ohm meter R x 1K scale, and if dial does not
move, the wire between two terminals is
disconnected.
-> Action: Replace the compressor.
* OLP may be operated by the following causes, so be sure to find and remove the cause.
(1) Operation at low voltage
(2) Defects of operation or starting device
(3) Overheat of compressor motor due to the condensing coil closing, condensing motor defects,
liquid line close, or injection capillary close.
Ohm Meter
R x 1K
TCL Air Conditioner Service Manual
6