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Not to Forget => Solar Heating and Heat Pumps => Topic started by: Gift on January 17, 2011, 08:56:20 PM

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Title: Heat Pump Fault?
Post by: Gift on January 17, 2011, 08:56:20 PM
Hi guys,

I've done a fair bit of googling to try find the answer, but haven't come up with anything definitive, and hoping someone here could shed some light on my problem ..

I had a Mitsubishi MSV-GE60 installed during winter last year - about 8 months ago, and it hasn't been right since day dot. It gets used infrequently, and the two times I went to use it during last winter (too lazy to light the fire) it failed to produce any heat at all. Turns out it had a leak, the installer was apologetic the first time, then extremely apologetic the 2nd time he had to sort/re-gas. He's spent the better part of 12 hours onsite trying to find the leak and/or repair the fault and seems genuinely apologetic that he's had to visit twice.

So I turn it on during the weeks heat-wave to cool us down, and don't get anything below 23 degrees blowing out (when set to the lowest setting of 16 degrees). It heats alright, pumping out air at 46 degrees when last checked (Unit set to highest of 31 degrees), but nothing on the cool side. Is this a sign of a low refrigerant levels? (again!).

The last two times it failed the output temperature didn't vary beyond 24 to 27 degrees on heat or cooling, but this time it seems to be 'one way'. Am I missing something simple perhaps? (filters are clean etc).

I'm thinking I need to get this replaced under warranty, since it's never been right,  and also considering getting a 2nd opinion from a different Heat Pump installer .. Just thought I'd ask around myself first.

Any insight would be much appreciated ..
Title: Re: Heat Pump Fault?
Post by: Jaxcat on January 18, 2011, 01:28:30 PM
Mate - Get it sorted under warranty and fixed or replaced while the warranty is still valid.  I would contact Mitsibushi and see who their accredited service agents are in your area and get them out to look at it.  As a precaution I would ring the installer and tell him that although you appreciate what he has done you need a heat pump that works - and that you are going to get a service agent in and if it ends up being diagnosed as an installation error then you want his permission to send the bill to him.   Legally you have to give the installer the opportunity to put right, but you've done this from what I can see - and obviously will have some evidence of his visits. 

This brand heat pump is not cheap and it should work like a dream - I haven't heard anyone complain about them.  With heat pumps you get what you pay for - the cheaper ones can be a bit dicey, but a brand like this which is at the top of the market should deliver hot and cold as required.

If the installer had trouble finding where the refrigerant is leaking then it could be a manufacturing fault and the service agent will have all the manuals necessary to diagnose this.

Don't delay - or next thing you know it will be out of warranty! 
PS - Next time consider putting in gas heating  ;D
Title: Re: Heat Pump Fault?
Post by: heatsol on February 29, 2012, 09:05:15 PM
It could be a jammed reversing valve, if the guy who "fixed it" didn't pump it down properly or use  a nitrogen purge while brazing(assuming it was a pipe leak) then you will end up with flakes of carbon from within the pipe due to the copper being brazed. This usually finds its way to the sliding portion of the reversing valve and jams it.
It could also be a genuine solenoid coil fault too, but rare with Mitsi's, there are good japanese units.
Just as a thought, simple one at that, are the batteries ok in your controller? wouldn't be the first time.
Sorry for the bad news, but like jaxcat says, get it on warranty cause us fridgeys aren't cheap if its out of warranty
Hope it works out