daikin RZQ160KV4A heat issues

[ads1]

HI
Was hoping to get some help after 3 years of intermittent problems & no help from Daikin !
My unit cools fine in summer but when used for heat it will usually be okay for 5 or 10 mins then blow cooler air inside.
When I switch the unit off leave for a few minutes it will sometimes heat again for a while then revert to cool blowing air, and other times it will just stay cool air.

Pressure tested and inspected for leaking gas but all seems fine & yesterday fully re-gassed and still have same issues -
Have run on emergency heat too - this heats for while then blows cool.

Really struggling here - would love to throw in the bin but at $10k for 3 years poor service want to try and get it working!!

Any Help please
Perth WA

[moideen]

have you checked 4 way reversing valve?

[Neddy]

When it blows cold air on heating does the outdoor contuine to operate?

[Paul84]

Turn the Setpoint to 30*C and High fan. Let the unit run for 30 minutes then check 'Service Mode 1 - Setting 10'. If there is a cause for the inverter to ramp down this will tell you why.

Set High Static Fan (23-6-02).

I've had the thermistor on the suction pipe of the reversing valve go out of calibration many times and result in compressor frequency dropping and appearing short of refrigerant and sometimes failing on 'U0'. It will also self diagnose through -

'Service Mode 1 Setting 10' - Indication of Step down - OTHER (H1P, H4P, H7P)

Hopefully this explanation makes sense and helps. I've attached a table, hope it works.

10512

[frank]

What type of indoor fan coil do you have...ducted, cassette, etc?

[moondawn]

Hi does the unit go into fault. if you have a hand held controller you can investigate the fault its in when it stops working. there is an easy procedure to follow where you cycle through the codes ie l4, e4 etc whichever code double beeps at you then this is the error code

I had recently a U0 error with kind of same symptons on a multisplit turned out compressor was ineffiecnt soft pumping.

cheers

[thewool]

Hi there, we are having exactly the same issue as ads1. (RZQ125KV) Its starts on heat for about 5mins then blows cold air. It seems worse the colder it is outside. If its under 10decC, it will will only get to 17 inside. If its 15degC, it will go up to 21 etc.

A Daikin service agent has been here on three occasions and replaced the PC Board, Air Sensors, the Discharge sensor and the internal controller (BRC1E61). It still does the same thing. They now suspect there is leaking gas somewhere. After reading the above post, I doubt it is the gas.

The problem is that my outdoor unit was installed on a very inaccessible pitched roof and the services agents are refusing to go up there again to do the gas test and I don't blame them. The fault lies with the installation company who didn't install it according to the instructions (ie. in a serviceable location). Unfortunately I will have to take them to court over this. Anyway, I am stuck between a rock and a hard place, with a baby and a freezing house!

Unfortunately I'm gonna have to get to bottom of it myself. I checked the controller and it came up with a U0 error.

Regarding your post, I don't know what you mean by 'Service Mode 1 Setting 10'. Is that on the outdoor unit?
Could you walk me through how to and where to get the error readings (H1P, H4P, H7P)?

Where is the thermistor on the suction pipe of the reversing valve? Is this hard to re-calibrate? Is the re-calibration a settings thing?

If I can get to the bottom of the issue myself, then at least I can set up scaffolding for the daikin people to fix it, rather then having to pay for scaffolding everytime they come and fail to fix it.

Also, if you have it, could you please send me the servicing and installation manual for the RZQ125KV.

Thanks!!!

[Paul84]

Hi thewool, unfortunately if you have to ask the 'how' and 'why' you probably shouldn't be doing the work - for safety reasons or causing further damage by tampering. The U0 fault on this model is USUALLY a refrigerant leak and/or faulty suction thermistor - this part can't be repaired and will need to be replaced. Costs less then $10.

I think Daikin have service departments in all states (atleast Sydney and Melbourne). You could request Daikin specific instead of a service agent.

Otherwise, If there is a fault with the installation and the unit is within 6years. Contact the installer as it will be under warranty as per Plumbing Industry Commission (PIC) and they can deal with the "access issues". If they don't follow through, make a formal complaint with the PIC.

[thewool]

Cheers, thanks for the prompt reply. I will definitely make a complaint to the PIC as the Daikin Service agent also told me to do. The problem is nobody is willing to get up there again to assess it and nobody is taking responsibility.

Short term I need to erect scaffolding. The problem is they have been here three times already (both Daikin technician and service agent) and can't find the fault. So I will need to keep paying for scaffolding until they find the fault.

Long term I will take the installers to VCAT and PIC to recover my costs.

I guess my question is: I know I can't do the repairs or any work and it was never my intention to, but is there anything I can do to find out what the issue is? Your post seemed to indicate there was an error reading I could get off the external unit. ie. the service mode. Or do I need a special machine for this?

Thanks again.