COMPONENTS TESTING (Continued)
CAPACITORS
WARNING
ELECTRIC SHOCK HAZARD
Turn off electric power before servicing. Discharge capacitor with a 20,000 Ohm 2 Watt resistor before handling.
Failure to do so may result in personal injury, or death.
Many motor capacitors are internally fused. Shorting the terminals will blow the fuse, ruining the capacitor. A 20,000 ohm 2 watt resistor can be used to discharge capacitors safely. Remove wires from capacitor and place resistor across terminals. When checking a dual capacitor with a capacitor analyzer or ohmmeter, both sides must be tested.
Capacitor Check with Capacitor Analyzer
The capacitor analyzer will show whether the capacitor is “open” or “shorted.” It will tell whether the capacitor is within its micro farads rating and it will show whether the capacitor is operating at the proper
Capacitor Connections
The starting winding of a motor can be damaged by a shorted and grounded running capacitor. This damage usually can be avoided by proper connection of the running capacitor terminals.
From the supply line on a typical 230 volt circuit, a 115 volt potential exists from the “R” terminal to ground through a possible short in the capacitor. However, from the “S” or start terminal, a much higher potential, possibly as high as 400 volts, exists because of the counter EMF generated in the start winding. Therefore, the possibility of capacitor failure is much greater when the identified terminal is connected to the “S” or start terminal. The identified terminal should always be connected to the supply line, or “R” terminal, never to the “S” terminal.
When connected properly, a shorted or grounded running capacitor will result in a direct short to ground from the “R” terminal and will blow the line fuse. The motor protector will protect the main winding from excessive temperature.
HEATING ELEMENT
(“WE” &”WY” Models)
All “WE” and “WY” models are equipped with a 3.3 KW heating element.
The heating element has two heater limit switches (bimetal thermostats) connected in series with it. The Primary limit located near the bottom, will open the circuit when the temperature reaches 130°F
Should the fan motor fail or filter become clogged etc., the high limit switch will open and interrupt the power to the heater before reaching an unsafe temperature condition.
Test the heater element for continuity below 130°F.
Heating Element
Not actual element - for reference only
DRAIN PAN VALVE
During the cooling mode of operation, condensate which collects in the drain pan is picked up by the condenser fan blade and sprayed onto the condenser coil. This as- sists in cooling the refrigerant plus evaporating the water.
During the heating mode of operation, it is necessary that water be removed to prevent it from freezing during cold outside temperatures. This could cause the condenser fan blade to freeze in the accumulated water and prevent it from turning.
To provide a means of draining this water, a bellows type drain valve is installed over a drain opening in the base pan. This valve is temperature sensitive and will open when the outside temperature reaches 40°F. The valve will close gradually as the temperature rises above 40°F to fully close at 60°F.
Drain Pan Valve
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