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

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(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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Contents Contents Revised EDITION-AFeatures Part Names and Functions Specifications Models PKH18FL, PKH24FL, PKH30FL, PKH36FLData Models PKH18FL, PKH24FL, PKH30FL, PKH36FL Performance DataHeating Capacity PKH24FL Performance CurvePKH18FL PKH36FL Condensing Pressure and Suction Pressure PKH18FL Cooling ModeHeating Mode PKH24FL Cooling Mode Indoor DB temperature F 80 psi.G Pressure SuctionPKH30FL Cooling Mode PKH36FL Cooling Mode Standard Operation Data SHF PKH18FL PKH24FL PKH30FL PKH36FLWith wind baffle D.B F if no wind baffle Operating RangeOutlet AIR Speed and Coverage Range PKH36FL Noise Criterion CurvesPKH30FL Band Center FREQUENCIES, HzUnit inch OutlinesPKH24FL PKH36FL PKH30FL InchPKH18FL PKH24FL PKH30FL PKH36FL Refrigerant System DiagramWireless Remote Controller Wiring Diagram Models PKH18FL, PKH24FL, PKH30FL, PKH36FL Wiring DiagramOperation FLOW-CHART Main OperationCooling Operation DRY Operation YESHeating Operation YES FAN Speed noMicroprocessor Control Outline of Microprocessor ControlIndoor Unit Control Cool operation time chartHow to operate Cool operationCoil frost protection Compressor controlStart condition Termination conditionsAuto vane control Auto ReturnDetecting abnormalities in the outdoor unit DRY operation time chart How to operate DRY operationFan control in DRY operation Display in Heat operation Heat operation time chart How to operateHeat operation Overheat prevention Overheat protectionBooster heater control Indoor coil temperature abnormality detection Defrosting operationTemperature range Initial modeMode change Auto return Auto vane controlCOOL/DRY operation Test run Timer operationTimer function Emergency operation Before emergency operationDip switch and jumper connector functions On remote controller board On indoor controller boardIndoor FAN Control Wireless remote controller pair number setting operation Model NoTroubleshooting Self-checkOther Troubles and Causes Wrong Wiring on Site Between remote controller and indoor unitHOW to Check the Parts Check pointsIndoor unit PKH24FL Disassembly ProcedureOperating Procedure PHOTOS&ILLUSTRATION PhotoRemoving the drain pan Removing the vane motorRemoving the intake grilles Removing the electrical heater Operating Procedure PhotosRemoving the line flow fan and the fan motor Parts List Electrical Parts PKH18FL PKH24FL PKH30FL PKH36FLT7W E14 Qty / set Wiring Parts No Parts Name SpecificationsT7W E13 R01 12G 621Structural Parts PKH24FL PKH30FL PKH36FLPage Distributed in Dec No.OC276 New publication, effective Nov Specifications are subject to change without notice