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View Full Version : Fujitsu auy30fuar icing problem



seb
19-03-2007, 07:29 PM
This unit frosts like hell. the 4 way indoor unit - someone 'serviced' it last week, apparently cleaned filters. any ideas - it shows no EEE codes at the moment but it did before i turned it off --- whoops...

The Viking
19-03-2007, 07:39 PM
We had a lot of problems with sticking relays in the Fujitsu cassettes.

They used to "under size" the compressor relay, located in the indoor unit.
After the relay seizes, you can turn the indoor unit off and the outdoor unit will continue to run.

just a thought....

seb
19-03-2007, 07:47 PM
will try that - i know the outdoor continued to run after i switched the indoor off at the remote pad - the unit started to creak - what do you think?

tait71
19-03-2007, 07:51 PM
sounds like a stuck or damaged relay/contactor a quite common fault on these just replace in but go slightly oversize:D

seb
19-03-2007, 07:55 PM
the relay is on the indoor unit isnt it? if so is it on the board? am i supposed to un solder it and replace? or replace board? or am i just stupid?

Brian_UK
19-03-2007, 09:10 PM
the relay is on the indoor unit isnt it? if so is it on the board? am i supposed to un solder it and replace? or replace board? or am i just stupid?
Now there's a leading question :D

No, use a screwdriver and unplug the wires, simple really.

Work back from the terminal block to find it.

The Viking
19-03-2007, 11:15 PM
Just remembered another thing....

We used to get replacement relays from FM (our Fujitsu supplier) FOC.
But as these were the same as the original ones and therefore failed again, we nowadays get "standard" relays from RS with a higher rating.
You will have to check on the control voltage as I can't remember what it is now.

(You might have guessed by now that the relay is separate from the board in these units)

seb
20-03-2007, 07:27 PM
fujitsu tec said high water switch - the one that activates the pump? (it also doesnt seem to pump - or is it just producing water when the indoor is technically 'off' so it leaks?

Brian_UK
20-03-2007, 07:41 PM
Can't quite see the link between a high water level and the coil freezing myself.

Also, how does the high water level switch manage to keep the outdoor unit running?

Was it a Fujitsu tech you spoke with or someone on the switchboard ;)

Do you have two problems with the unit perhaps?

seb
20-03-2007, 07:58 PM
no - the correct guy. im just real scared of looking a prat on this one - its in a £90 per 100g chocolate sales place on the kings rd and im the 3rd man in.....

Electrocoolman
20-03-2007, 08:01 PM
Are we COMPETENT?

Brian_UK
20-03-2007, 11:09 PM
And are we CONFIDENT?

Remember, nobody is a genius, refrigerant gases do things slowly so you need to be able to watch and observe.

If you have a multimeter then the test of the suspect relay is a piece of cake, sort that one out first and you are 95% of the way to resolving the water leaking problem.

As a case in point, relax and think slowly and carefully.

I went to site today after someone else who had problems with a wall mount leaking water. He's all worried about gas shortage and it icing up and all sorts of things.

I got to site, poured water into the drain pan and watched as it very slowly drained away. I therefore put the possible gas problem to the back of my mind.

Looked at the drain pipework, it ran slightly uphill and the installers had over-glued the plastic 20mm and formed a dam of glue in an elbow.

Stripped off the elbow and the water ran away.

Moral, don't panic and don't imagine.

stuartwking
21-03-2007, 11:18 PM
Good words of advice,.I had same problem on same kit last week,outdoor running when no demand, stuck relay right enough.

robin r33 gtr
22-03-2007, 09:35 PM
If the relay is stuck on and the indoor unit is off it will ice up. If then you switch the unit on and off and the relay does not stick the ice will melt ,but as the indoor unit is off the condensate pump is not running so the water will build up and trigger the high level switch.

answer . Drain off indoor unit (is there a rubber bung) change relay.