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MS8C / MS8H (208-230V)
HEAT MODE (I FEEL MODE OFF)
Heat Mode - Indoor temperature set point range is 61°F and 86°F (16°C and 30°C)
NOTE — Reversing valve is energized in heating mode.
HEATING MODE
FIGURE 56
Protective Functions
Delays that normally protect the compressor are disabled during defrost cycles:
1. Minimum three (3) minute compressor time delay between operating cycles.
2. Minimum six (6) minute compressor run time between operating cycles.
Heat ON
If room ambient temperature is equal to or less than the remote control set point plus 3.6ºF (2ºC), the unit cycles heat
ON
. If it
has been three (3) minutes since the last heat demand, the compressor and outdoor fan will cycle
ON
. The indoor fan will
operate according to the cold blow prevention function.
Heat OFF
If room temperature is equal to or greater than remote control set point plus 9ºF (5ºC), the compressor will cycle
OFF
. The
outdoor fan will cycle
OFF
30 seconds later. The indoor fan will operate for 60 seconds after heat cycles
OFF
.
Indoor Fan Operation - Heating
The fan speed is determined by the difference between the room ambient temperature and the remote set point temperature.
Cold Blow Prevention
The system prevents cold air from blowing into space during heating operation. After three (3) minute time delay, one of the
following indoor fan cycles will occur:
*
If the indoor ambient temperature is
greater
than 75ºF (24ºC): If the coil temperature is equal to or greater than 104ºF
(40ºC) the indoor fan will run at low speed for 1 to 2 minutes. If during that time the coil temperature rises above 106ºF
(42ºC), the indoor fan will ramp to a preprogrammed heat speed for those conditions.
*
If the indoor ambient temperature is less than 75ºF (24ºC): If the coil temperature is equal to or greater than 106ºF (42ºC)
the indoor fan will run at low speed and within one minute, the indoor fan will ramp to preprogrammed heat speed for
those conditions.
Reversing Valve Operation
The reversing valve is energized in heating and will stay energized for two minutes after the compressor is de-energized. The
reversing valve is energized 2 seconds before the compressor is energized.
