Defrost Tempering Kit - Lennox HARMONY III Installation, Setup And User Manual

2.1.6.

Defrost Tempering Kit

A defrost tempering kit (67M41) may be implemented in a dual-fuel (Option 3)
system. This kit consists of a thermostat probe/switch which is installed between
the furnace and the evaporator coil to turn the furnace on (at 80°F) and off (at
90°F) during a defrost cycle. This tempers the discharge air and protects the
compressor from high refrigeration pressures during defrost. The following figure
show the defrost temperating kit components and see "Figure 4. Discharge Air
Sensor Installation" on page 8 for location of the probe.
LIMIT CONTROL
MOUNTING
BRACKET
STRAIN
RELIEF
LABEL
Figure 19. Defrost Tempering Limit Control
WHEN FULLY ASSEMBLED,
TABS ARE BENT DOWN TO
HOLD CONTROL AND WIRES
IN PLACE.
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