COMPONENTS TESTING (Continued)
HEATER ELEMENTS AND LIMIT SWITCHES’ SPECIFICATIONS
All heat pumps and electric heat models are equipped with a heating element and a limit switch (bimetal ther- mostat). The limit is in series with the element and will interrupt the power at a designed temperature.
Should the blower motor fail, fi lter become clogged or air-
flow be restricted etc., the high limit switch will open and interrupt the power to the heater before reaching an un- safe temperature condition.
TESTING THE HEATING ELEMENTS AND LIMIT SWITCHES
WARNING
ELECTRIC SHOCK HAZARD
Disconnect power to the unit before servicing. Failure to follow this warning could result in serious injury or death.
Testing of the heating elements can be made with an ohmmeter or continuity tester across the terminals after the power wires have been removed. Test the limit switch for continuity across its input and output terminals.Test below the limit switch’s reset temperature.
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 assists 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.
Bellows Assembly
Drain Pan Valve
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