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View Full Version : Daikin Compressors and VSD failures







piewie
21-02-2012, 01:55 PM
Iíve just recently returned to the commercial a/c game having been in the industrial for a sector for a while.
I have recently had a run in with a Daikin split package small 3 or 4 kilowatt. But it has left me seriously doubting my credentials.
First it had an error code that showed that the compressor or vsd was grounded. By switching it off then on again the error disappeared and it ran for a few days then bang and it tripped the supply breaker. I did an insulation test and the compressor was down to earth. Ordered a new compressor and fitted it but alas on power up it showed a comms error between indoor and outdoor unit. Called up the Daikin Australia help line and was told that because the compressor was grounded that we should have changed the PCB (VSD control board) . Ordered a new board and swopped it out sure enough one of the microchips was blown clean off the board. Started up the unit but no joy. Indoor unit runs for a while then shows A7 code Outdoor PCB fault. Called up the Daikin Australia help line again and was asked to check the DC Cap on the VSD all okay. Then I was asked to use a diode meter and do some measurements between red and blue wires on the condenser fan motors. The readings were about 0.736 chap on the phone says they should be about 0.8 . The chap from Daikin tells me that I need to order 2 new fan motors and another new PCB (VSD control). His story goes something like this. Failure of the compressor caused the VSD PCB to fail we replaced it but because we did not change the fans this then caused the new VSD PCB to fail.
Holy moly I have never heard anything like this before. If I had a pump motor connected to a VSD and the motor went down to earth I would definitely not expect the VSD to fail to destruction. Secondly how on earth are you expected to quote on repair work.
Has anyone else ever had a situation like this? Can anyone else shed some light on it?

Thank goodness this is a Daikin Warrantee job and even better still we were not the installing contractor.

Many Thanks