COMPONENTS TESTING (continued)
HEATING ELEMENT
All heat pumps and electric heat models are equipped with a heating element with the exception of model YS10M10. The other “YS” and “ES” models are equipped with a 3.3 KW element. The “YM” and “EM” models are equipped with a 4.0 KW element. The “YL” and “EL” models are equipped with a 5.2 KW element.
Heating Element
Sample
The heating element contains a fuse link and a heater limit switch. The fuse link is in series with the power supply and will open and interrupt the power when the temperature reaches 199°F or a short circuit occurs in the heating element. Once the fuse link separates, a new fuse link must be installed.
NOTE: Always replace with the exact replacement. The heater element has a high limit control. This control is a bimetal thermostat mounted in the top of the heating element.
Should the fan motor fail or filter become clogged, the high limit control will open and interrupt power to the heater before reaching an unsafe temperature condition.
The control is designed to open at 110°F ±6°F. Test continuity below 110°F or when it is cooled off.
HEATING ELEMENT (Heat Pump Models)
The heating element for the “Y” model is energized by an outdoor thermistor via the electronic control board. The outdoor defrost thermistor is adjusted at
apredetermined temperature of approximately 30 degrees Fahrenheit and sensed for two consecutive minutes, to stop the compressor and turn on the heating element.
TESTING THE HEATING ELEMENT
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 elements can be made with an ohmmeter across the terminals after the connecting wires have been removed. A cold resistance reading of approximately 14.5 ohms for the 3.3 KW heater, 11.9 ohms for the 4.0 KW heater and 9.15 ohms for the 5.2 KW heater should be registered.
DRAIN PAN VALVE
During the cooling mode of operation, condensate which collects in the drain pan is picked up by the con- denser 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 con- denser 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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