Goodman Mfg R-410A manual Checking Loss of Charge Protector, Checking High Pressure Control

SERVICING

		T3	T2	T1
VOLT/OHM	CC
METER
		L3	L2	L1

Ohmmeter for testing holding coil

Voltmeter for testing contacts

TESTING COMPRESSOR CONTACTOR

(Three-phase)

S-11 CHECKING LOSS OF CHARGE PROTECTOR

(Heat Pump Models)

The loss of charge protector senses the pressure in the liquid line and will open its contacts on a drop in pressure. The low pressure control will automatically reset itself with a rise in pressure.

The low pressure control is designed to cut-out (open) at ap- proximately 50 PSIG. It will automatically cut-in (close) at approximately 95 PSIG.

Test for continuity using a VOM and if not as above, replace the control.

S-12 CHECKING HIGH PRESSURE CONTROL

WARNING

The high pressure control capillary senses the pressure in the compressor discharge line. If abnormally high condensing pres- sures develop, the contacts of the control open, breaking the control circuit before the compressor motor overloads. This control is automatically reset.

1.Using an ohmmeter, check across terminals of high pres- sure control, with wire removed. If not continuous, the con- tacts are open.

3.Attach a gauge to the dill valve port on the base valve. With power ON:

LINE VOLTAGE NOW PRESENT.

4.Start the system and place a piece of cardboard in front of the condenser coil, raising the condensing pressure.

5.Check pressure at which the high pressure control cuts- out.

If it cuts-out at 610 PSIG ± 10 PSIG, it is operating normally (See causes for high head pressure in Service Problem Analy- sis Guide). If it cuts out below this pressure range, replace the control.

S-15 CHECKING CAPACITOR

CAPACITOR, RUN

A run capacitor is wired across the auxiliary and main wind- ings of a single phase permanent split capacitor motor. The capacitors primary function is to reduce the line current while greatly improving the torque characteristics of a motor. This is accomplished by using the 90° phase relationship between the capacitor current and voltage in conjunction with the motor windings so that the motor will give two phase operation when connected to a single phase circuit. The capacitor also re- duces the line current to the motor by improving the power factor.

CAPACITOR, START

SCROLL COMPRESSOR MODELS

Hard start components are not required on Scroll compressor equipped units due to a non-replaceable check valve located in the discharge line of the compressor. However hard start kits are available and may improve low voltage starting characteris- tics. Only hard start kits approved by Goodman® or Copeland should be used. "Kick Start" and/or "Super Boost" kits are not approved start assist devices.

This check valve closes off high side pressure to the compres- sor after shut down allowing equalization through the scroll flanks. Equalization requires only about one or two seconds during which time the compressor may turn backwards.

MODELS EQUIPPED WITH A HARD START DEVICE

A start capacitor is wired in parallel with the run capacitor to increase the starting torque. The start capacitor is of the elec- trolytic type, rather than metallized polypropylene as used in the run capacitor.

A switching device must be wired in series with the capacitor to remove it from the electrical circuit after the compressor starts to run. Not removing the start capacitor will overheat the capacitor and burn out the compressor windings.

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