4-2 Heat Mode Operation
The Heating mode operation is similar to the Cooling mode operation. The VALVE and FMI are mainly
controlled by the value of (RAT – SPT). In the graph above, the FMI is operating in AUTO speed mode.
Therefore, the FMI speed changes automatically according to the (RT - SPT).
NOTES
1. After VALVE is switched off, the FMI runs for 30s in order to purge heat from the indoor coil.
2. The FMI will not be turned on until the indoor coil temperature is warm enough to prevent the supply of
cool air (see COLD DRAFT PREVENTION mode for details). The indoor fan can change speed only after it
has operated at the same speed for 30 sec if in AUTO and 1 sec for the other settings (High, Med, Low).
VALVE
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