Daikin fault codes

[fridge doctor]

Hi all,

Could anyone help me with a Daikin problem ?
I have an older (R22) system which is showing me a fault code of U4. This, refers to a transmission error between indoor units ? The system however is just a single split. Am I interpreting the U4 error code wrongly, does it mean something else?

Thanks guys,
Trevor

[The Viking]

Yes,

You are wrong M8.

U4 refers to the communication between indoor and outdoor units.

Normal suspects includes wiring faults and defect PCBs, the outdoor one being known to fail more frequently than the indoor.

Good luck...


(U9 is the one for faulty communication between indoor units)

[ginzo]

check also
1. loose connections
2. power supply to outdoor PCB
3. Fuse on outdoor PCB
4. reset power and if it still flashes U4 replace PCB

[frank]

Or as we sometimes do - put the comms wire through the high level float on the pump, so when the pump conks out, the units stops and you see a U4 error code

[airconadam]

Also have a look if the interconnection cable form indoor to outdoor is near or on mains power cables that can also cause a u4. Good luck let us know what it is thanks

adam:D

[Stuart]

When you say it is an older model unit I presume that it has been working in its present position for a while. So this being the case First check the interconnecting cables to ensure they have not been chewed by rodents. Check visually if poss also cos if belled out they may show a false reading. Check outdoor unit if LED A is flashing check the voltage on the indoor unit between 1&2 then between 2 & 3 If the voltage is 0Volts replace indoor PCB's. If outdoor LED A is not flashing change outdoor pcb

Good luck

[fridge doctor]

Definitely no prob with the wiring. At the outdoor, I'm getting mains OK but 0v on the single control cable. There are no flashing LEDS on the outdoor board. The (lower) indoor board has LED A flashing, and LED B off. So I don't know which of the three boards I should replace ?
Thanks

[Stuart]

Hi
Looks to me like you have faulty outdoor pcb's.
Indoor pcb's sound fine with the led A flashing.
But check that all connections are good to the circuit board. As Daikin will be unhappy at replacing operational PCBs.
Let me know how you go

Stuart

[Makanic]

Also look for Dead lizards

3 lizards Fried this Board :confused:
http://server7.pictiger.com/img/635502/picture-hosting/dead.php
http://server7.pictiger.com/img/635502/picture-hosting/dead.php
http://server7.pictiger.com/img/635502/picture-hosting/dead.php

[paul_h]

I did a service on an old diakin, and it had six fried lizards, and one confused and lonely alive lizard looking for it's friends.
The a/c still worked too.

[Makanic]

I did a service on an old diakin, and it had six fried lizards, and one confused and lonely alive lizard looking for it's friends.
The a/c still worked too.

Must Be A Aussie Thing

1 lizard Melted & Shorted the tracks which in turn fried the IC ..

[paul_h]

Yeah that photo you showed was an inverter, and a lizard will fry an inverter beyond repair easily, no matter what brand, I've seen about 7 a year with mice, lizards or frogs killing the control PCB. This daikin I saw the seven lizards in was a conventional type, not much in them besides fan control, HP switch and sump heater.

[Makanic]

Yep Dont you love Inverter technology, I wouldnt of got a call out & repair if it wasnt a inverter.
My old man Still Believes in the KISS theory
Keep
It
Simple
Stupid
Less Complicated, less to go wrong..

[fridge doctor]

I will be going back to this unit today, but still not sure how to proceed. I will check for lizards, as I had not looked at the underside of the outdoor board on my previous visit. Also I can report that the comms cable is embedded as one of the five in a 5 core cable link. The unit however is 7 years old, so this is not likely to be troublesome now I am thinking. Would you guys replace the inner and outer boards instead of trying to narrow it down to one ? I'm not too happy with that as the customer is an elderly couple probably on limited resources and living in a not too great apartment complex.
Thanks for any advice

[Temprite]

I will be going back to this unit today, but still not sure how to proceed. I will check for lizards, as I had not looked at the underside of the outdoor board on my previous visit. Also I can report that the comms cable is embedded as one of the five in a 5 core cable link. The unit however is 7 years old, so this is not likely to be troublesome now I am thinking. Would you guys replace the inner and outer boards instead of trying to narrow it down to one ? I'm not too happy with that as the customer is an elderly couple probably on limited resources and living in a not too great apartment complex.
Thanks for any advice

Your outdoor board sounds dead to me.

Did you check the control fuse on the board if this is blown you will also get no flashing LED.

If your board was Ok and your coms wiring was broken you should still get a flashing light on outdoor PCB.

[frank]

I'll be in Cyprus the first week in October, on my hols.

Shall I take my meter with me and have a looksee for you :D:D:D:p

[VRVForever]

Lets forget VRV/splits for just for now, can you pass on the details of your wine supplier as I have lost them.
Hope you are well and I will ring you shortly.
VRV Forever likes a drink and we need your assistance.
MP

[frank]

Lets forget VRV/splits for just for now, can you pass on the details of your wine supplier as I have lost them.
Hope you are well and I will ring you shortly.
VRV Forever likes a drink and we need your assistance.
MP
VRV - sorry I couldn't make it the other week. 'bout time we had a few beers.
I now get my wine from here (http://www.majestic.co.uk/webapp/wcs/stores/servlet/ContentView?storeId=272&catalogId=&langId=-1&contentPage=locator) - Cheers ;)