Daikin RZP145DV1 problem

[Lampuki]

My Daikin RZP145DV1 suddenly stopped working with no error code. Daikin themselves do not seem to know what is wrong, and suggested replacing all the PCBs and condensor fan motors - an expensive exercise! Is it worth doing this in a step-wise fashion - eg replacing inverter board first, etc or should I just accept Daikin's suggestion? Here is a run down from our A/C tech:


Switched on AC, set temperature conroller to 30C.
Checked "SERVICE MONITOR where the green LED is flashing and the 4 red LEDs are off. SERVICE MONITOR saying eveything is normal
AC goes through its start up procedure, runs for approx. 30s and then shuts down.
Checked SERVICE MONITOR again where the green LED is flashing and the 4 red LEDs are off. SERVICE MONITOR saying eveything is normal.

Checked compressor windings for continuity, earth leakage, and current draw. Compressor is fine
Checked power supply and all connections

Checked all fuses found good

Thermisters checked @ 21C ambient

Checked thermistors R1T 23kohms (24kohms)
Checked thermister R2T 27kohms (24kohms)
Checked thermister R3T 284kohms (280kohms)
Checked thermister R4T 24kohms ( 24kohms)

Figures in () are the values the thermisters should read at 21C, thermisters are fine

Contacted Daiken technical support (Mark) discussed my findings where he suggested to also check the condensor fan motors.(CFM)
Reason being that they are often times responsable for causing damage to printed circuit boards (PCB) on inverter AC.
I checked both CFMs as per his instructions but could not find any mechanical damage.

Marks suggestion was to replace all PCBs on the outdoor unit and also the CFM. " Do not replace the PCBs without replacing the CFMs"

Here is the email from Daiken displaying part numbers and prices:



DAIKIN SERVICE SPARE PARTS daikinspare@daikin.com.au


RZP145DV1

Control 1693498 $570.00

Resistor 065339J $3.01

PCB, Inverter 1697320 $407.13

A3P 1301201 $16.68

Active Module 1283187 $209.90

Fan motor x 2 1283194 $218.42each



Any help will be greatly appreciated!

[regcooldude]

You set the controller to 30 ? Is that in cooling mode ?

[install monkey]

daikin alarms have to go out of range 3 times before they display the fault- check loose connections on the interconnect, ensure no3 signal is terminal block or crimped in the isolator. is this a hardwired controller on it?
check external condensate pump doesnt have a failsafe contact wired in, pull the drain plug to see if a lot of water comes out,does this only happen in cooling mode?

[install monkey]

aikin inverters are prone to pressure transducer failing so it thinks its short of gas- its a 3 pin connector and should be a 0 to 10vdc on the black,had a k series that started up for 10seconds then stopped and did nothing,with no alarm codes- spent 3 days checking every failsafe on the system- did have 9 compressors and 30 indoors

[frank]

Does the unit run in Emergency mode?

[AbsoluteWDJ]

Check for any fault code history

[Mick13]

i had a very similar unit, an rzp125dv1 do almost the exact same thing. the compressor would start and run for about 10 seconds or so then cut out. turned out it was the suction pressure transducer, the unit thought it was short of gas due to the transducer playing up. do this: take the transducer off the suction line and put it on to a bottle of gas, and see if it runs then. when i did this on the unit i was working on the unit ran beautifully, the compressor ramped up all the way and everything seemed great. when u take the transducer off the unit will likely go straight into fault so u will need to reset it first.

test the transducer in comparison to daikins specs (available in the service manual) and see what u come up with. when my compressor started up, the unit thought it was pulling a vacuum with the readings the transducer was returning.

Also do the LEDs on the outdoor pcb light up? sometimes they can help shed some light, as they may help display faults before it shows up on the wallpad.