Trouble with a daikin split, RXD71JVEA

[paul_h]

My first daikin split!
It's an inverter about 5 years old, operation LED on the indoor unit keeps flashing.
Indoor unit powers up, no heat or cooling, outdoor unit not switching on, hard reset does nothing (symptoms return immediately without system trying to start.)
No significant voltage on the serial cable, I think these are similar to panasonics, where there should be about 25v there or if not, the outdoor unit is faulty.

I don't know how to get any error codes from the wireless remote and it seems as the outdoor is dead as a doornail. No significant voltage on the serial interconnecting cable.
240v to the outdoor PCB, all fuses OK. Looking at the outdoor, the old familiar active filter module is there (input 240V DC, output 320v DC). So I started here, no output, no input. I know if there's a short somewhere the power relay will disable circuits, so I disconnected everything for the power PCB, retested, hoping to find some sort of DC output from the PCB to the leads that went to the control PCB and active filter module. I got nothing.
So, here's the part where I come here, oping to find someone who knows as much about the electronics for a daikin as I know about fujitsu.
Is it the power PCB that does the DC voltage output, and what terminals should they be on?
Is there a diode bridge hidden away on the heatsink, or something other than stuff visible from the top of the board that could be at fault?
It started raining so I had to stop working on it, but want to know some things before I go back. Like what are common causes and where to trace the power circuit. The compressor meggered OK, but are there other things that screw up daikins (like condenser fans) that need checking first?
Control board looked OK, the power board looked OK (fuses OK, tracks OK, capacitors and solder OK), AFM looked OK, but there was a film of something over some of the cables above the power board, a very thin coating of a tar like substance left behind when something goes bang, but unable to find the carbon cratered culprit.

[DoD]

wow, u know your stuff huh, right for checking fault codes with wireless controller, hold down "cancel" button and aim controler at unit, you will hear a "beep" now on your controller you will see "00" flashing, press "cancel" again and you will hear it "beep" once more and a different code will flash on the controller, keep pressing "cancel" until you hear a "long beep" and then when you hear that it will show you the fault code on the controller, also i was just thinking that i had a similar problem with a different type of inverter and it turned out that the p.c.b wasnt set correctly by the factory and they had to send me a little blue plug to stick on the outdoor p.c.b i fitted it and it ran fine after that.. :0) hope this helps paul....

[paul_h]

I kow a fair bit about inverters generally because I work for the company that does repairs for fuji and panasonic.
Down here, except for daikin I think, it's up to the manafacturers to support their product during warranty, not the installers.
The manufacturers contract all the repair work out to 2-4 companies, so I have to attend almost every broken fuji and panasonic a/c in the whole of the city. So I've seen a lot of them, and fuji has their own tech support guy you can phone or he will meet you on site at no cost if you get a troublesome unit.

Thanks for that anyway, I was looking for something like that. Panasonic has something similar where you press the 'test' button for ~10 sec, then use the time set up/down buttons to scroll through the codes and listen for beeps.
Trust daikin to make it complicated by using an obscure button.

Anyone else? I thought daikin was popular in europe going by the posts here, I thought someone would have come across this fault or had manuals or factory support?

[DEVIL]

paul_h u can find the fault allso by the LED on the outdoar unit, there are 4 reg, and one green, i thinck, my the whay all of them blinck or stay on u can find the problem like with the remote control
i had some similar cases, but some with a compressor fault, and coudn't find the problem, averithing whas ok, on testing, wit the multimeter, but daikin has a "inverter checker" that test's compressor, extreamly expensiv, i can't aford one, and in romania, only Daikin hase one

and had some trobels with a tranzistor, pozitioned, on the left of the PCB, that ad + , - and ~ ~ , i don't know how how is exactly caled in english, it's with 4 legs.
there are 2 on the pcb colse togheder, or one, depending on the unit, and that whas shorting.
u can't start the unit widouth the compressor cabels on becuase the pcb checks that.
but if u know the error code, i can give u more info, what to check and what could it be, anywhay at daikin u can only by the hole PCB, and i don't thinck u can find parts, i couldn't

[paul_h]

paul_h u can find the fault allso by the LED on the outdoar unit, there are 4 reg, and one green, i thinck, my the whay all of them blinck or stay on u can find the problem like with the remote control
i had some similar cases, but some with a compressor fault, and coudn't find the problem, averithing whas ok, on testing, wit the multimeter, but daikin has a "inverter checker" that test's compressor, extreamly expensiv, i can't aford one, and in romania, only Daikin hase one

and had some trobels with a tranzistor, pozitioned, on the left of the PCB, that ad + , - and ~ ~ , i don't know how how is exactly caled in english, it's with 4 legs.
there are 2 on the pcb colse togheder, or one, depending on the unit, and that whas shorting.
u can't start the unit widouth the compressor cabels on becuase the pcb checks that.
but if u know the error code, i can give u more info, what to check and what could it be, anywhay at daikin u can only by the hole PCB, and i don't thinck u can find parts, i couldn't
Yeah like I said, outdoor unit completely dead, no LEDs light up on it at all.
That thing you mentioned with the ~~ and + - is most likely the diode bridge. AC voltage goes in "~~", DC voltage comes out "+ -", that's a pretty critical component of most inverters powering up, as all the control and compressor etc runs off DC voltage.
But as said before, thats what I couldn't find on this daikin unit.
This is an older unit, with distinct parts, which is why I kind of knew my way around it. I know what you mean with "whole PCB supplied only" as most newer ones are designed like that, eg the panasonics I service. But the lay out of this one is like the very early inverters, seperate control, afm and power PCBs.
The fault codes were handy, but not really necessary for this case, as a dead outdoor unit is a dead outdoor unit, all the indoor unit is going to tell me with fault codes is communication error. Getting the codes is handy if its a thermister fault etc, as it tells you which one.
The compressor could be stuffed, but it checks out OK with a megger, so if the compressors stuffed it would be seized, at least all the power and cmms would be working at that stage so I can check everything else.

But anyway, all I wanted to sort out is the power circuit. That's where you have to start with these things, without that, you have nothing. Once you have DC power from the diode bridge, then you can test the control board, compressor, CF etc etc, as like I said before, you disconnect everything, then power it up one at a time to find out the faulty component if you don't have much info on the unit.

[paul_h]

Just an explaination of what I'm trying to achieve, here's how the fuji rep showed me on testing the power circuit.
First of all, if it powers up ie: power relay clicks on, TX valve energises, system times out and compressor goes to start but fails. Then you're looking at compressor failure or IPM etc.
Likewise if theres blown up stuff like board or fuses.

But if the power relay doesn't come on, then there may be no DC voltage to the control PCB due to the systems over current/short protection. That's where you have to trace the power circuit, disconnecting things that may be faulty, as the system detects faults and cuts power.
There should be 240V ac to a diode bridge (edit: or whatever your countries mains voltage supply is), if theres not, disconnect the ac leads to the diode bridge and check for 240v on the bare wires that went to the diode bridge. If that's there now, but wasn't when it was connected to the diode bridge, then a short at or after the diode bridge is cutting the system out. If there's no ac voltage, then the fault is in the ac voltage section and test ends, replace the 240v power section.

If there's 240v there, disconnect the dc output from the diode bridge, reconnect the ac and retest. there should be 240v dc from the diode bridge, if not, the diode bridge itself is faulty. If there is, then something after the diode bridge is faulty.
And so on, checking the bare outputs of the diode bridge to the active filter module, then the bare outputs from the AFM, then 320v dc from that to the control pcb with everything unplugged, to the control pcb with the tx, then condenser fan motors etc etc. when you lose voltage, you've found the component cause the short and loss of power.
edit: Of course you can bypass all these tests if you check the control PCB power supply. If everything is OK, and you have 320-380v dc at the control PCB but it doesn't power up, then you have a faulty control PCB. But I'm trying to explain it as per this case, where there was no voltage on the DC circuit at all.

[DEVIL]

whelll, at daikin it's harder
u can't make the unit start widthout one cable unpluged.
because it test's everithing, valves, compressor, fan, some part's of pcb, and if somnthing dose not pass the check, it dosen't even tray to do enithing , just sends the error to the indor, and that's all, but however , in u'r case, if no LED flesh, espeshialy the green one, there must be somthing on the first, litle pcb, that actualy it's not a pcb, it's out of plastic, and hase some components on it. But u should remember, outdoor unit's uzualy have 2 fuses, one on the big PCB, and one on the litle one that i whasy talcking abut. If the fuse on the litle one is burned, not curent is passed to the big one and important one.
if it whould be somthing like a capacitor or somthing else on the main pcb, u should still see the green LED fleshing or on. u should check if the main PCB is energized.
The litle one u can't see, only if u take the main PCB, out, and the litle one is positioned on the lef corner, and it comes out with the connexion cables going to the indor.

[Temprite]

Yeah like I said, outdoor unit completely dead, no LEDs light up on it at all.

G'day Paul

If you check the fault code on this unit it will probably show U4 (communication error).Not much communication going on there with no green LED flashing.

First check if filter board has power supply,check 3.15 amp control fuse on board. If you are really keen check ceramic resistor should be 51 ohms from memory.

I would also check the fan motor because if this is stuffed it will take out new boards. Pull the fan blade off and spin the shaft between thumb and finger, should get 1.5 turns approx. If it is stuffed probably would only spin half a turn. You can't get a proper result from this with fan blade attached.

If you are within yelling distance of the ocean, I would replace all the boards and treat any new boards with a silicon type spray or lacuer. Put all connectors on before treating though.:)

[paul_h]

G'day Paul

If you check the fault code on this unit it will probably show U4 (communication error).Not much communication going on there with no green LED flashing.

First check if filter board has power supply,check 3.15 amp control fuse on board. If you are really keen check ceramic resistor should be 51 ohms from memory.

I would also check the fan motor because if this is stuffed it will take out new boards. Pull the fan blade off and spin the shaft between thumb and finger, should get 1.5 turns approx. If it is stuffed probably would only spin half a turn. You can't get a proper result from this with fan blade attached.

If you are within yelling distance of the ocean, I would replace all the boards and treat any new boards with a silicon type spray or lacuer. Put all connectors on before treating though.:)Thanks, btw this unit is across the bloody road from the ocean, every hex head screw rusted away to nothing, lots of corrsion on the panels. The guy was surprised when I suggested replacement of the unit, "it's only 5 years old, and just out of warranty. I shouldn't be up for replacement so soon" he said.
I let him know it needs at least some outdoor circuit boards replaced, plus a good hit of kill-rust and screws replaced with stainless steel ones. It's funny how people will OK $500+ on repairs, but not look at a replacement unit which offers another 5 year warranty.

[SteveCass]

Can't help with the fault, but you say this machine is near the sea? As well as the rusting parts, if the coil has not been treated or coated it will rot alot quicker, meaning hp troubles sooner than most. I have installed stuff near the sea and coating is always an optional extra, might be worth pointing this out to the customer, on top of the other work. Just ditch the old condensing unit and fit a new, modified one!!

Steve

[Temprite]

Thanks, btw this unit is across the bloody road from the ocean,
I let him know it needs at least some outdoor circuit boards replaced,

If this unit is right next to the ocean I would change all three outdoor PCB's because if you dont you will be back there soon enough changing the board you missed.Make sure you treat the new boards.

Recomended retail on those three boards is about 780.00 plus GST.

If you get the boards right there is no reason why the unit wont last for a long time the compressors rarely fail in these units from my experience.

[paul_h]

If this unit is right next to the ocean I would change all three outdoor PCB's because if you dont you will be back there soon enough changing the board you missed.Make sure you treat the new boards.

Recomended retail on those three boards is about 780.00 plus GST.

If you get the boards right there is no reason why the unit wont last for a long time the compressors rarely fail in these units from my experience.
I just thought I'd follow this up as I'd forgotten about it and I know it's annoying when the OP doesn't follow up with results.
Well the sea was to blame, the pins on one of the a/c plugs on the main board had corroded at the solder joint. So I just replaced the control PCB as the corrosion was too far gone and it runs OK now. Treated it with lacquer, sprayed the O/U with killrust and replaced the screws with stainless steel ones so it won't be such a drama just removing the panels for the next service. Thanks all for the replies.

[ozairman]

Good one, glad to see that you did manage to fix the unit and more so actually identify the problem. I did try some digging for a manual but couldn't come up with anything on this one.