Blocked air-con unit

[Johnny Walker]

Hi,

I need some advice, there was a break-in attempt to a shop where the burglars knocked off the outside unit of a small air con.
The owner didn't even find it out until he switched it on and it wasn't working. I made new pipe connections and regassed the system but it doesn't work. No matter how much gas I put inside, the suction pressure stays under 0bar and no cooling happens (after a while the unit cuts off with a big whoosh, I think it must be some safety pressure cut-off)
I think the unit sucked up some dirt and its blocking the expansion device. The question is, if I take it apart and unblock it, it might still have some particles inside, not even mentioning that it was running for a while without the pipes connected to it, sucking up a lot of air, dust and dirt, so how can I effectively clean the system up? Is there any recommended procedure or special filters I have to install? Is the compressor needs new oil?

It is a small toshiba 2.5kw inverter run on R410a.

[hyperion]

Sounds as if you have at least got moisture in the system. There could also be contaminants restricting the expansion valve or inline filter/strainers. Safely reclaim the refrigerant. If need be carefully disconnect the expansion valve. It may be prudent to replace this item. Then purge through each section of the system with OFN to make sure that you have removed as much of the mositure and contaminants as possible, then triple vac, breaking the vacuum with OFN and then weigh in the correct refrigerant charge. If you do not know the correct amount, contact Toshiba Technical for the figures. You might then be lucky to get it going. It is going to be quite time consuming to get the system clean again.

[p8er76]

I think that small system have none exp. valve but capalairy injection. but for sure you have some blocking.
Found out where the blocking is, get it out (if possible). put sight glass with moisture indicator. and vac for long time. see also the collor of your oil in vac pump. if it gets white you have moisture.

[Brian_UK]

Do a cost comparison between spending a lot of time and effort in trying to clean up the unit and possibly getting it going again and the price of a new, warranted, unit.

Is it subject to an insurance claim?

[Johnny Walker]

Thanks for all answers. It is not subject to insurance.
Probably i will check how much a new would cost and let the customer decide about it.
Its pretty shame that the unit is just a bit over 1 year old.
Actually I will take it apart and clean inside anyway just to see what was the problem. I will post it as well.
Thanks again for the advice

[cadwaladr]

replace it,but this time put some guards around it.

[Magoo]

Original unit probably for sale on ebay.

[Johnny Walker]

Well, I spent yesterday night on the unit and found the problem: moisture... or I would rather say water. Lots of water inside the coil and that was blocking the capillary.
I took it apart section by section, cut out all filters and replaced, flushed with nitrogen a lot as well and finally regassed it.
I spent lots of time on it and am pretty sure it didn't worth as I think there is still lots of moisture inside, as I said the coils were properly flooded with water (wondering how did it get so much inside)...
Anyway for now its fine and at least the kitchen staff can breath again in the basement. It will be replaced later, lets see how long will this one last...

Thanks for advice, you guys were right I should have just gone for a new one, but at least I have learnt a lot about air-con units, it was good for experience.

Thanks again

[Brian_UK]

Thanks for the update.

The water was probably drawn in when the pipes were broken.