Protection Functions & Controls - Heat Controller VMC09SB-1 Service Manual

5. Protection Functions & Controls
5.1 Five Seconds Stand-by (fan)
• The indoor unit fan will begin to rotate after 5 seconds of the unit being turned on.
5.2 Two Minutes Stand-by (comp.)
• After the compressor cycles off, it will not restart for a minimum of 2 minutes.
5.3 Hot start Heatpump Only
• To prevent cold air from blowing in the room upon starting up the unit in heating mode, the indoor fan will not rotate
until the heat exchanger temperature reaches 30˚C(86˚F).
5.4 Freeze prevention (Protection of the evaporator pipe from frosting)
Heatpump Only
• If the indoor pipe temperature is below 0˚C(32˚F) within 7 minutes after the compressor operates continuously in cool-
ing mode, the compressor and outdoor fan will turn off.
• When the indoor pipe temperature is 7˚C (44.6˚F) or higher after a 2 minute pause/cycle off of the compressor, the
compressor and outdoor fan will turn on according to the condition of the indoor air temperature.
6˚C(42.8˚F)
3˚C(37.4˚F)
NOTE: Some Models are different by T1.
Only for training and service purposes
Comp. free
Comp. Step 4
Comp. Step 2
T1
Comp. off
T1: 0 ~ 2°C(32~35.6°F)
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Part 2 Functions & Controls
Indoor pipe
temp.
7˚C(44.6˚F)