TM9-4120-400-14
1-11. REFRIGERATION CYCLE. - continued
The SERVICE VALVES (11) are provided for charging, and general servicing of the high and low
pressure sides of the refrigerant system.
The LOW PRESSURE SWITCH (17), the HIGH PRESSURE SWITCH (13) and the PRESSURE
RELIEF VALVE (12) are provided to protect the unit from damage due to pressure extremes.
The flexible METAL HOSE ASSEMBLIES (2) and (18) provide vibration isolation between the
compressor and other components of the refrigeration system.
a. When the MODE SELECTOR is set for HIGH HEAT, all heating elements, located behind the evaporator
coil are energized. These elements are protected from overheating by a thermal cutout switch Half of the
elements are thermostatically controlled by the TEMPERATURE SELECTOR. The remaining half are on all of the
time. When set for LOW HEAT, only the thermostatically controlled elements are energized.
b. The two speed fan can be set for either HIGH or LOW operation during heating.
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