Danfoss Heat Pump Troubleshooting Guide download pdf (Page 31)

VMIFB202

Outdoor sensor/Defrost sensor

Action:

Check that the outdoor sensor/defrost sensor is installed according to the installation instructions and that it is correctly calibrated.

Measure the ohms at the sensor to check it displays the correct value.

Install according to the instructions and calibrate, if necessary. Or replace the defrost sensor.

The defroster shunt does not regulate as it should

Action:

Manually test to check if the defroster shunt opens and closes the ow over the defroster tank. If the motor switches position when

testing, but defrosting still does not function, remove the motor and try closing and opening the valve by hand by pressing in the

spring loaded spindle. If it should be stuck or not spring back replace the insert.

If the shunt motor does not react, check measure the signals to the shunt. These are 24vac + and - signal. See wiring diagram!

If the motor is defective, replace it. If the insert jams, remove and clean/lubricate it, or replace it.

Troubleshooting Guide Outdoor unit and defrosting problems

Motor for shunt

Defrosting 24Vac

Photograph taken

from left side.

temperature ohm

-30 1884

-25 1443

-20 1115

-15 868

-10 681

-5 538

0 428

5 343

10 276

15 224

20 183

25 150

30 124

35 103

40 86

1 2 ... 26 27 28 29 30 31 32 33 34

No comments

Danfoss Heat Pump Troubleshooting Guide Page 31