Friedrich SM21J30A4, Руководство по обслуживанию

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TEST:
1. Remove leads from thermostat.
2. Turn thermostat knob clockwise to its coldest position.
3. Test for continuity between the two terminals. Contacts
should be closed.
4. Turn thermostat knob counterclockwise to its warmest
position.
5. Test for continuity - contacts should be open.
NOTE: The thermostat must be within the temperature
range listed to open and close.
THERMOSTAT ("YQ" Model Only)
See Figure 28.
This thermostat is single pole-double throw, cross ambient
with a range of 60° to 92°F and a differential of ±2°F. Terminal
"2" is common.
providing that the mode was set for cooling and the set
point temperature has not been met in the room.
THERMOSTAT ("SQ & KQ" Models) - See Figure 27.
Thermostat is used to cycle the compressor on and off at the
comfort level desired. The thermostat has a range from 60°
±2°F to 90° ±4°F, with a differential of 5°F. Turning the knob
clockwise lowers the indoor room temperature setting, while
tur ning the knob counter clockwise r aises the indoor
temperature.
TEST:
Remove wires, turn thermostat to its coldest position. Check
for continuity between the two terminals. Turn thermostat to
warmest position, check continuity to see if contacts open.
NOTE: Temperature must be in range listed to check
thermostat.
Figure 29
THERMOSTAT (SC Model Only)
Figure 28
THERMOSTAT ("YQ" Models Only)
To maintain the comfort level desired, a cross ambient type
thermostat is used. The thermostat has a range from 65° ±2°F
to 87° ±3°F. The thermostat bulb is positioned in front of the
evaporator coil to sense the return air temperature. Thermo-
stat malfunction or erratic operation is covered in the trouble-
shooting section of this manual.
TEST:
1. Remove leads from thermostat.
2. Turn thermostat knob clockwise to its coldest position.
3. Test for continuity between the two terminals. Contacts
should be closed.
4. Turn thermostat knob counterclockwise to its warmest
position.
5. Test for continuity - contacts should be open.
NOTE: The thermostat must be within the temperature
range listed to open and close.
Figure 27