Heat Controller VMH C Series Service Manual page 28

VMH 30, 36 SerieS
Service Manual Heat Controller
The unit runs with T3＜37.5°F(3°C) for 40 minutes and T3 stays lower than 21°F(-6°C) for more than 3
minutes.
The unit runs with T3＜37.5°F(3°C) for 80 minutes and T3 stays lower than 25°F(-4°C) for more than
3 minutes.
Condition 2: If T4>32°F(0°C),
The program judges according to condition 1, if the two items are satisfied, then it judges if T2 has
decreased more than 9°F(5°C). When T2 has decreased more than 9°F(5°C), it enter the defrosting
mode.
Condition 3: No matter what value T4 is, if the machine runs with T3＜37.5°F(3°C) for more than 120
minutes and T3 keeps lower than 25°F(-4°C) for more than 3 minutes, the machine will defrost, no
matter if T2 drops for more than 9°F(5°C) or not.
Condition of ending defrosting:
If any one of following items is satisfied, defrosting will finish and the machine will turn to normal
heating mode.
T3 rises to be higher than 59°F(15°C).
T3 rises to be higher than 46°F(8°C) and remains for 80 seconds.
The machine has run for 10 minutes in defrosting.
The defrosting action：
60 seconds
70 seconds
30 seconds
10 seconds
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