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MS8C / MS8H (208-230V)
COLD BLOW PREVENTION
This function prevents cold air from blowing into space in heating mode. After a three (3) minute time delay, one of the
following two indoor fan cycles occurs:
1. When the following conditions are met:
A. Indoor ambient temperature is greater than 75°F (24°C).
B. Coil temperature is equal to or greater than 104°F (40°C).
The indoor fan will run at low-speed for one to two minutes. If during that time the coil temperature rises above 106°F
(42°C) the indoor fan will ramp to a pre-programmed heat speed for those conditions.
2. When the following conditions are met:
A. Indoor ambient temperature is equal to or less than 75°F (24°C)
B. Coil temperature is equal to or greater than 106°F (42°C)
The indoor fan will run at low-speed, and within one minute, the indoor fan will ramp to a preprogrammed heat speed for
those conditions.
SYSTEM PROTECTION FEATURES
COMPRESSOR PROTECTION
In order to protect the compressor, there is a 3-minute delay after the unit shuts off. The delay occurs even during a call for
heating or cooling.
INDOOR COIL FREEZE PROTECTION
When the unit is running in the COOL or DEHUMIDIFICATION mode, the indoor coil can freeze due to any of the following:
*
Low system charge
*
Reduced indoor airflow (restricted filter)
*
Restricted refrigerant flow
*
Low ambient temperature (outdoor)
*
Low indoor system load
The indoor coil sensor monitors the coil temperature continuously. If the coil temperature drops below 30.2°F (-1°C), the
compressor and the outdoor fan (30 seconds later) will be turned
OFF
. When the coil temperature rises above 42.8°F (6°C)
and the compressor has been off for 3 minutes, the compressor and outdoor fan will cycle
ON
.
INDOOR COIL FREEZE PROTECTION
FIGURE 60
Indoor Fan Operation
When compressor is cycled ”OFF”, the indoor fan will continue to run at a preset speed.
