Daikin Ryn35cvmb7

[Kirky]

Been called to a Daikin split system on a server room previous engineer says compressor has gone but I'm not sure the unit is not in fault compressor just doesn't seem to be getting a start signal it's not down to earth it just doesn't wanna start not power to the compressor but power to condenser fan could it just be the pcb some internal fuse blown or something

[sedgy]

hi kirky, you say , its not down to earth , have you tested the windings?
sedgy,

[luboboi]

verification is easy. measure the resistance of the windings and the housing. appliance must have a range exceeding 2000k

[monkey spanners]

Hi Kirky,

Is it an inverter unit or does the compressor start dol?

Any fault codes or flashy lights?

[Brian_UK]

You say the fan runs, is there power to the contactor on the control side?

Check the safety circuit.

[marc5180]

On a side note, donuts Brian?

Sorry to hijack

[Kirky]

Thanks for getting back to me. The unit isn't showing any fault lights the LED on the PCB is flashing away show normal conditions the condenser fan runs I've got power at the outdoor unit going into the PCB but no power onto the compressor it is not inverter driven. In the past when the compressor is faulty the compressor will at least try to start and usually take out the circuit breaker or pop a fuse but on this unit nothing happens am I wrong in thinking that if it was the windings that the compressor would at least try to start

[Kirky]

Looks like the compressor is protected by a temp sensor mounted on the head of the compressor can't remember it's proper name a little rusty but it is wired directly into the pcb as is the comp and fan

[monkey spanners]

Have you checked for voltage at the compressor terminals?

If there is power then put your amp meter on the wire to the compressor and see if it is pulling any current, it could be seized but not burnt out, it will pull LRA for a few seconds then go to 0 for a few minutes and then repeat, it would keep doing this till the motor gets hot enough to short out and blow a fuse.

If there is no power then check the wiring back to the board and then check the relay or contactor. It would be worth checking the capacitor too if its single phase.

[Andy AC]

Check the contactor, even if the coil is energised, doesn't mean the power is getting through, the contacts may be burnt out.

Andy

[Kirky]

There isn't any power at the compressor terminals it isn't even trying to start it's a very simple unit power directly into the pcb with everything else wired directly from the pcb. If I've got power into the pcb but not at the compressor terminals then it's gotta be the board maybe the capacitor gone or something I've dealt with faulty compressors in the past and they at least try to start but this one does nothing it doesn't throw the breaker

[luboboi]

if not go to the compressor voltage problem will Vrelo compressor on board

[luboboi]

if not go to the compressor voltage problem will be the compressor relay on board sorry

[Brian_UK]

There must be a power relay on that board feeding power to the compressor, check power across the relay. Also bypass the relay to check if the compressor starts after having checking the motor windings.

[Brian_UK]

On a side note, donuts Brian?

Sorry to hijack

OK, yup, just noticed; two virtual jam ones en route. (Damn, I hate people with long memories. )

[Kirky]

Cheers guys for all your help the unit is old and in pretty bad condition so we just gona replace full system. Someone had installed the condenser under a overflow pipe so the unit is soaked and covered in moss

[airconadam]

On a side note, donuts Brian?

Sorry to hijack

Trust you to be thinking of food again (curly chunk)