Problem Fujitsu Air Conditioning split

[pie man]

Hi fellow engineers,

I was hoping someone might be able to help me on a problem I have been given at my works office.

The problem: unit will not cool or heat. A few weeks ago was asked to replace the indoor board for this unit - was only installed 8 months ago :eek:. The guy who installed it said it was blowing the boards fuse. Anyway this did not solve the problem, I suspect this unit has not worked since day one.

Model details are: Fujitsu split R410a Inverter outdooor AOYR24LCL S/N: E001601.

So get the call to look at it again. Attached gauges to lp (no hp fitting at ball valves). The standing pressure was at 12 bar. Ran in cool and heat mode on test run, the unit didn't fault out (red and green leds both on and off at the same time on the indoor). Noticed the outdoor condensor fan would run for several seconds and cut out, but nothing from the compressor. I have checked supply on the IPM PWB red/white/black wire connections to compressor, all tested approx. 140v to earth, therefore supply to compressor. Also did an insulation test to each compressor winding, all tested fine and nowt down to earth.

Then contacted Fujitsu technical, not sure what I did wrong but I was asked to test the voltage for a brown wire on this IPM PWB which connects to a FILTER PWB to earth...this caused a spark and a bang....this board ended up burnt out :confused:.

I hope this is enough information and would appriciate any suggestions you guys/or gals might have!

Pie Man :)

[croc1774]

A bang is never a good sign.. I would say you have blown the board.
When the unit is in test mode it will bypass all safety devices, so thats why you wouldn't get any error codes.
Try reset of outdoor power then look at led's on outdoor unit, if there is a problem they will flash(if you need manual pm me).

[pie man]

Thanks croc,

If you have details or a manual that would be great, yeah got a new board on order don't know if this board was on the way out so I shall see what happens. As I recall, the outdoor board on normal cool / heat mode the red LED light wasn't flashing or lit up. Fujitsu tech said on test it would eventually error out but will try what you have suggested for sure. Will be carefull not to blow the new board!

Thanks for replying,

Pie Man

[Tayters]

not sure what I did wrong but I was asked to test the voltage for a brown wire on this IPM PWB which connects to a FILTER PWB to earth...this caused a spark and a bang....this board ended up burnt out :confused:.


Hi Pieman,

Did you do as i've done in the past - still have your meter on the resistance scale?
Luckily when I did it, it was on a fridge compressor and everything lived another day!

There is an amusing video on Youtube of a bloke mending a flat screen TV. I think he does a similar thing but for him he's at a customers house who is filming him at the time.

Cheers,
Andy.

[pie man]

Did you do as i've done in the past - still have your meter on the resistance scale?
Luckily when I did it, it was on a fridge compressor and everything lived another day!

...Hi Andy,

It was defo on AC Voltage setting! Almost destroyed my meter..still works but I nearly fell off my steps in shock! Took the main breaker out and the staff gave me some stick... just hope this new board works and the bloody compressor will run!

Pie Man

[install monkey]

www.fgeurofred.co.uk (http://www.fgeurofred.co.uk) for fujitsu technical/service manuals

[pie man]

Thanks install monkey! Will check it out