Mitsubishi Electronics PKH30FL Compressor control, Start condition, Coil frost protection

Models: PKH24FL PKH30FL PKH18FL PKH36FL

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(1)Compressor control

(1)Compressor control

1 3-minute time delay

To prevent overload, the compressor will not start within 3 minutes after stop.

2 The compressor runs when room temperature is higher than set temperature.

The compressor stops when room temperature is equal to or lower than the set temperature.

The compressor maintains the previous state when the room temperature minus the set temperature is 0 degrees or more, or lower than 2 degrees.

3 The compressor stops in check mode or during protective functions.

4Coil frost prevention

To prevent indoor coil frost, the compressor will stop when the indoor coil thermistor (RT2) reads 34°F or below after the compressor has been continuously operated for at least 16 minutes or more. When the indoor coil temperature rises to 50°F or above, the compressor will start in a 3-minute(w2) time delay.

w2 When the indoor coil temperature is 30°F or less, the compressor starts in 6 minutes.

NOTE : By turning OFF the dip switch SW1-3 on indoor controller board, the start temperature of coil frost prevention changes from 34°F to 36°F.

5Coil frost protection

When indoor coil temperature becomes 5°F or below,coil frost protection will proceed as follows.

<Start condition>

After the compressor has been continuously operated for 3 minutes or more,and the indoor coil temperature has been 5°F or below for 3 minutes,the coil frost protection will start.

<Coil frost protection>

Compressor stops for 6 minutes,and then restarts.

lf the start condition is satisfied again during the first 10 minutes of compressor operation,both the indoor and outdoor units stop,displaying a check code of“P6”on the remote controller.

<Termination conditions>

Coil frost protection is released when the start condition is not satisfied again during the allowance, or when the COOL mode stops or changes to another mode.

(2)Indoor fan control

Indoor fan speed depends on the remote controller setting.

However, if an outdoor unit abnormality is detected, the indoor fan speed will be low, regardless of the remote controller setting.

When the outdoor unit abnormality detection is released and the fan speed returns to the set speed, the quiet cycle control will work.

(a) Normal control

( i) Fan speed depends on the remote controller setting regardless of the thermostat on/off.

(ii) Fan speed will remain on low if an abnormality in outdoor unit is detected. (5 minutes)

5 minutes

SET

low

5 minutes

SET

low

OFF

1Start-up of outdoor unit abnormality detec-

tion.

2Release of outdoor unit abnormality detec-

tion.

3Unit stop due to outdoor unit abnormality with P8 indication.

NOTE 1 : Fan stops immediately if the unit stops or the check mode is started.

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Mitsubishi Electronics PKH30FL, PKH36FL Compressor control, Start condition, Coil frost protection, Termination conditions