Electrical Component Test - Sharp AF-05CML Service Manual

Table of Contents

AF-05CML

It becomes clear that good equipment and maintained properly must be used in order to remove air and moisture from the

system.

When a vacuum of 1,000 to 500 microns is reached, block off the vacuum pump from the system.

This is done by closing the value between the pump and system. If the micron gauge does not increase above 1,000, the

system is free of moisture and no leak exists. If the micron gauge increases to higher levels moisture or a leak exists.

LEAKS

Several methods are used to detect leaks in systems.

Electronic Leak Detectors are very sensitive and are able to detect leaks down to 1/2 ounce per year.

A good electronic leak detector is generally far better in locating very small leaks.

Halide Torch be sure the room is free from refrigerant vapours. Watch the flame for the slightest change in colour.

A very faint green indicates a small leak. The flame will be unmistakably changed to green or purple when large leaks

are encountered. To simplify leak detection pressurize the system to approximately 75 lbs.

Some leaks can be located by a visual inspection of the system components and solder joints and if oil is found at

any given location it generally is a sign that a leak exists at that point due to the fact that flame does carry oil with it

travels through the system.

Soap Bubbles

Liquid detergents can sometimes assist in finding small leaks by brushing detergent on the suspect area and watching

for bubbles. Before applying detergent be sure that the system is pressurized.

Tap line devices are permissible for diagnosis only they are not suitable when evacuating the system. After the diagnosis

has been made they must be removed so that the system will be restored to a hermetical sealed condition.

SELECTOR SWITCH

(1) Remove the lead wires from the selector switch.

(2) Using a volt-ohm-meter set on resistance range, check continuity

between terminals as indicated below.

FAN OPERATION

LOW-COOL OPERATION 1-2, 1-8

MED-COOL OPERATION 1-4, 1-8

HIGH-COOL OPERATION 1-6, 1-8

INSULATION TEST

Check the resistance between the terminal and SWITCH shaft.

Reading must be more than 10MΩ at DC 500V.

THERMOSTAT

(1) Take the wires off the thermostat terminals.

(2) Set the selector switch of a volt-ohm-meter (or a tester) on the

resistance range.

(3) Connect the probes to the thermostat terminals and check continuity between terminals.

(4) Turn the shaft of the thermostat clockwise. Continuity between terminals: OFF

Turn the shaft of the thermostat counter-clockwise. Continuity between terminals: ON

(When ambient temperature is more than 86˚F, continuity between terminals may not change to OFF.)

INSULATION TEST

Check the resistance between the terminals and thermostat shaft. Reading must be more than 10MΩ at DC 500V.

RUNNING CAPACITOR AND FAN CAPACITOR

CAUTION: DISCHARGE THE RUNNING CAPACITOR AND FAN CAPACITOR BEFORE TOUCHING CAPACITOR

OR WIRING.

(1) Discharge capacitor by shorting terminals.

(2) Take the wires off the capacitor terminals.

(3) Set the selector switch of a volt-ohm-meter (or a tester) on the resistance range.

(4) Connect the probes to the capacitor terminals and watch the indicator swing.

The indicator does not swing at all ..... Open.

The indicator swings but does not return ..... Shorted.

The indicator swings, then returns a moment later ..... Good.