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Louwie · Jul 24, 2013, 12:53 AM

I bought a split unit air conditioner 12000 BTU. The one with the quick connectors. I did not suck vacuum on it and did not do it with the other two that I bought know this one is not working it push gas through to the evaporator and start making cold for about 1minit then the evaporator gets hot again(not real hot but ambient temperature).
The manufacture sent out a technician to come and have a look at it and he said that it is because I did not suck vacuum and now there are nitrogen in and this damage the compressor and the evaporator.
Is this possible, it is R410 gas.
He replaced the complete outdoor unit and it is still doing the same.
When he unscrew the quick connectors to put on the new outdoor unit the liquid gas came out completely black, his answer on this is nitrogen in the gas.
I know it is a mouth full but I pleas need answers, I cannot see why two others is running without problems and this one is not working.

Joshdta · Jul 24, 2013, 01:56 AM

Is this a mini split wall unit?

Louwie · Jul 24, 2013, 04:32 AM

Yes this is the mini split wall unit (MSR3-12HRN1-QE)

Joshdta · Jul 24, 2013, 03:50 PM

Well there is no nitrogen in the system inless you put it there so that can't be a issue. Not pulling a vac is not good but should not cause the problem you are having. Did you see this black freon?

Louwie · Jul 24, 2013, 10:18 PM

Yes when he open the hi pressure side there was sum black liquid coming out not much, I will say it might be dirty pips or sum led with the soldering.
If I look at this situation I think that the expansion valve is blocked or faulty, because with the new outdoor unit (compressor)he put on we go the same the evaporator get cold for +- 1 minute and then back to ambient temperature, if you switch it over to heating the same happened it heat for +- 1 minute and then switch back to ambient temperature.