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speeds to reduce rate of indoor temperature change
and avoid passing set point. As temperature of indoor
space moves farther from set point compressor, indoor,
and outdoor motors adjust to increase rate of indoor
temperature change and remain close to set point.
System tries to remain running, minimizing the number
of start / stop cycles. This provides the most uniform
space conditioning comfort levels and best overall
system efficiency.
• In Heating Mode reversing valve is de-energized, except
during defrost. When air handler calls for heating,
if compressor is not in ASCT, it will start softly then
increase in speed as necessary to balance indoor
heating load with outdoor ambient, while minimizing
compressor starts and stops. Actual compressor speed
is based on room temperature differential, indoor fan
speed, and compressor rated frequency parameters.
Minimum compressor run times and outdoor coil defrost
are in place whenever compressor runs in Heating
Mode. Condenser mounted Electronic Expansion valve
(EXv) continuously adjusts refrigerant flow to maintain
15ºF (8.3ºC) superheat at compressor. Refrigerant
vapor travels through large diameter tube of line set
to air handler where heat is transferred into air. Once
refrigerant is condensed, sub-cooled liquid returns to
condenser via small diameter tube.
• As temperature of indoor space moves closer to set
point compressor, indoor, and outdoor motors adjust
speeds to reduce rate of indoor temperature change
and avoid passing set point. As temperature of indoor
space moves farther from set point compressor, indoor,
and outdoor motors adjust to increase rate of indoor
temperature change and remain close to set point. If
system has optional electric heat, and heat pump alone
(stage 1) can not reduce set point differential, optional
electric heat energizes (stage 2) of heat. System tries
to remain running, minimizing number of start / stop
cycles. Providing uniform space conditioning levels and
best overall system efficiency.
CONDeNSeR OPeRATION