Daikin UATYP560AMY1 showing E10 fault

[hyperion]

Recently during the snowy/icy weather the above fault code has appeared. Daikin advise that this is low presure in Circuit 1. On initial inspection it appeared as if the compressor had stopped pumping as the suction and discharge pressures were the same. The unit was left switched off over the weekend andf a return visit made to get a 2nd opinion before changing the compressor. Switched the unit power on and both compressors started up and ran normally in heating. Running pressures seemed to eb OK. Watched both compressor go through a defrost sequence and retrun inti the heating mode. Only difference between the two outdoor coil is that the No.1 circuit does not completely clear the ice. Received a callout last night that E10 code is being displayed. Apart from a further build up of ice, are there any further suggestions asto what to check next on this unit. I recall that at this time last year the unit faulted into E10, but once we got there and cleared the large ice build up, the fault did not re-occur. Is there a way of adjusting/extending the defrost period on this unit.

[VRVIII]

Recently during the snowy/icy weather the above fault code has appeared. Daikin advise that this is low presure in Circuit 1. On initial inspection it appeared as if the compressor had stopped pumping as the suction and discharge pressures were the same. The unit was left switched off over the weekend andf a return visit made to get a 2nd opinion before changing the compressor. Switched the unit power on and both compressors started up and ran normally in heating. Running pressures seemed to eb OK. Watched both compressor go through a defrost sequence and retrun inti the heating mode. Only difference between the two outdoor coil is that the No.1 circuit does not completely clear the ice. Received a callout last night that E10 code is being displayed. Apart from a further build up of ice, are there any further suggestions asto what to check next on this unit. I recall that at this time last year the unit faulted into E10, but once we got there and cleared the large ice build up, the fault did not re-occur. Is there a way of adjusting/extending the defrost period on this unit.

Hi Hyperion,

The E10 error code refers to a refrigerant shortage judgment on circuit 1, I don’t think these units actually have an LP switch so the error must be judged based on sensors (this might also include internal compressor sensor/safety).

These scroll compressors have bi metal disk that will allow a high to low bypass when compressor internals starts to overheat, this in turn will quickly cause the motor protection to trip.

I would concentrate on circuit 1 defrost problem & why the motor is overheating,
Suggested checks:

• Verify correct refrigerant charge
• Check calibration of all sensors and verify they have good contact in the sensor pocket
• Is reversing valve faulty or sticking
• Are there any signs of a refrigerant flow restriction when operating heating or cooling mode.