View Full Version : Mitsubichi HI Inverter re-installation - Cheshire. Help please!

19-08-2017, 04:13 PM

I'm looking for an air conditioning engineer to re-install a Mistubishi HI Inverter outdoor unit. The unit was removed from the wall for building works and now requires installation in a new location. Existing pipework and wiring are sufficient to reach new location. Indoor unit to remain as is.

We're in South Cheshire.

Any recommendations would be most welcome.

Thanks :-)

monkey spanners
19-08-2017, 08:53 PM
Why not get the company who removed it to put it back?

19-08-2017, 10:38 PM

they came round and told me that there was no gas in the system (it has been working perfectly well up until the day they came - and I mean last night!)... they demonstrated no pressure in the red line, though I had not been present up to this point to see what they were up to. Then they told me that there was oil in the pipework. This, they said, was indicating a problem with the compressor....oil being sucked past the pistons into the lines....

Zero gas in the lines, yet it had been working normally to this point....oil in the lines, I subsequently discover is the nature of these systems...

He gives me a load of BS about needing nitrogen to flush the oil out, but then says he has forgotten his nitrogen bottle...

So, it's not worth moving the unit because a replacement compressor will cost more that 800 quid and they can do me a nice new "Sinclair" system for not much more than that...

Then they tried to nick the socket that I'd lent them to get the unit off the wall and I started to smell big BS...

In the end I paid a hundred quid just to make them go away. I smell a very big rat here. It was like an episode of rogue traders. He had no bottle to collect the refridgerant. I suspect he just vented the system to show zero on the guage and then opened the low line to show some oil spluttering. In the meantime he's going to quote for a new (el cheapo) system....

I went on line and found that a typical replacement 2.7kw compressor (OEM) can be had for around 250 quid. A whole new inverter system similar to mine from MHI can be had for 500 quid....

Also, I found out a bit more about how oil is employed in ac systems...

I am quite sure there is nothing wrong with my existing system, they have just identified an opportunity to do one on what they think is an unsuspecting old fool.......

Anyway, I won't be inviting them back! I now need someone to do the job properly, rather than try to rip me off...

monkey spanners
20-08-2017, 02:35 PM
Sound like you've had a lucky escape then they're either incompetent or dishonest. Usually you can shut the tap in the small line and run the system to pump all the refrigerant into the outdoor unit, then shut the tap in the big line and cap both the connections off. This is how they come from the factory.

Not sure with Mitsubishi but some manufacturers have recommended contractors who have passed their training, or even the local wholesalers would be able to recommend someone who makes few warranty claims.

21-08-2017, 01:40 AM
If your system was working perfect before it was disconnected, then looks its compressor was ok, but don't know the techs you have called did some thing to it. If you was present all the time then may be it is still okay, For oil in the lines it is normal it runs with the gas and you will have a spill if a line opens under pressure. Go for some other Techs and get at least three opinions. If compressor is defective and system and lines were kept open for long time
then better to go for NEW unit.
There are many black sheep's in our industry everywhere who wants to become millionaire in days.

Peter paner
21-08-2017, 03:36 AM
well. can i will contact you. (https://www.quangminhhanoi.com/)

22-08-2017, 06:30 PM
well. can i will contact you. (https://www.quangminhhanoi.com/)

Thanks Peter, but I really need someone in or around Cheshire, UK, not Viet Nam.