Any refrigeration experts here (ASHP)?

[ProDave]

I am trying to comission my ASHP and can't get it working, and finding the supplier so far frankly useless.

 

At first I thought it was a controls issue, because the web based diagnostics is not showing the water flow rate, so I thought it was refusing to run because it thought there was no water flow. But now I am coming to the conclusion that is a red herring and the on line diagnostics are not much of a reflection on what is actually happening.

 

So I am trying to do some self diagnostics and wonder if it's a refrigerant problem.  Here is the refrigerant pipework diagram from the manual

 

 

What is happening, you give the heat pump a heating demand.  the fan starts up. The compressor starts up and ramps up in speed.  After a short while the output pipe from the compressor starts to warm up. Notice the term warm up, it is by no means "hot" just warm.  Nothing much seems to flow around the regrigerant circuit, you can just detect slight warmth in the pipe going into the reversing valve, but I can't detect any warmth making it past there out of the reversing valve and certainly no warmth reaching the plate condenser.

 

After a couple of minutes the inverter ramps up a bit faster in speed then it all shuts down.

 

Am I right to be thinking this may be a lack of regrigerant in the system and that might be the problem rather than an electrical fault?

 

I am trying to formulate an understanding of what might be wrong before I go back to the supplier wihich probably won't be until Monday now.

[Onoff]

I just asked an AC guru I know from site, he wrote:

 

"If it’s new and no refrigerant has been lost on installation then perhaps check the operation of the reversing valve as it can only do one operation at any one time 
If it’s going in through two circuits at once the compressor may shut down due to the transducer reading pressure/ temps that aren’t correct"

 

Cheers Terry for the pointers if you're reading this!

[ProDave]

Just to clarify it was sold to me as "new" 11 months ago, but I found out when I got it it was not actually "new".  It looks in new condition i.e. it has not been installed anywhere outside, but the paper labels on all the connectors on the wiring loom suggest it might have been used as a training or demo unit.

 

Anyway I have just found the "event log" and that confirms it is tripping on a "low pressure"  fault so I think that confirms it either has a leak, or was supplied to me with no refrigerant.  Monday's phone call could be "interesting"

 

I did a quick search for refrigeration engineers up here and only one answered the phone this late on a Friday.  He estimated £160 for the labour to re gas it and a similar amount for the gas. That sounds like a piss take to me. I can't think it's more than an hour to re gas it, and how much does 1.8Kg of R410A actually cost?

 

Can you ask your mate what a proper re gassing cost would be?

 

And to be clear it's a monoblock unit.

[Onoff]

Says Terry:

 

"R410A is anywhere from £80 to £100 a kilo in this part of the world 
When he runs it feel the temperature across the drier and the check valve
If there’s a temp diff the drier may be choked or the check valve may be stuck"

[ProDave]

So the gas cost I was quoted is about right, I need to work on getting someone cheaper for the labour. I will let you know how the conversation goes on Monday when I suggest the supplier pays for the re gassing.

 

As I say when you run it, it is ONLY the output from the compressor that gets at all warm. That warmth never makes it anywhere near far enough around the circuit so at the drier and check valve both input and output pipes to both are stone cold.

 

As the gas is so expensive, is is possible to fill the system say with compressed air to check for leaks first  (obviously without trying to run it like that) and if the pressure holds, vent the air and fill with gas?

 

Can I make any pressure tests at either of the Schrader valves? what sort of pressure would we expect at each?

[Jeremy Harris]

Regards the labour, if the bloke is going to do it properly, then he needs to do the following:

 

Fit a vacuum pump and pump the refrigerant side down to ensure there is no moisture in there.

 

Do a vacuum test to check for gross leaks.

 

Weigh in the exact amount of refrigerant (he'll put the bottle on a scale and measure the weight of refrigerant added to get it right).

 

Add fluorescent dye when filling with refrigerant (which may well come with dye already in).

 

Let the temperature and pressure stabilise for 15 to 20 minutes.

 

Check for leaks with a UV lamp.

 

Test the unit and check that the low and high pressure sides are at the right working temperature and pressure.

 

Just filling the unit up with more refrigerant, without doing the checks, could well be a waste of money, as there has to be a good reason for the unit having lost gas.  Generally they are like refrigerators, and rarely just lose gas without there being a leak somewhere, and as they are sealed systems the leak can be very small and hard to locate without the dye and UV light.

[Onoff]

This just back. I was going to say nitrogen too so I must have picked something up from him! 

 

"Wouldn’t put anything else in but OFN (oxygen free nitrogen ) as all the others may have consequences 
Anything put in  will require vac out to about 1 torr and some gases become explosive when mixed with fridge oil 
The only way to check the refrig side is to put some fridge gauges on it to assess gas levels
Does sound short or possibly completely empty to me , compressor discharge should be to hot to touch"

[ProDave]

Given the history., I am hoping it is not a leak, but was supplied to me with no or low gas.

 

When I first got it, I tried to run it up, but with no water connected. I expected the input to the PHE to start getting very hot very quickly and I would have then shut it off. but it didn't. it behaved as it is now, the compressor ran for a couple of minutes and nothing got hot.

 

I didn't do any more then as I thought it was shutting down because of no water flow.  And to be clear I didn't just run it and cook the thing, it honestly did not get hot. So if it's got no gas, that is how I received it.

 

EDIT Just looked back at the event log for 10 months ago and it is logging water flow AND low pressure as faults so it was low on gas then, it has not just leaked out over the last 10 months.

[ProDave]

Looks like you can buy the gas in bulk (as I would expect a refrigeration engineer to do) for about £29 per Kg https://www.ebay.co.uk/itm/R410A-Refridgeration-Gas-Air-Con-Virgin-Bottle-11-35kg-Unlimited-Quantity-s/302759201166?hash=item467ddac98e:g:MbAAAOSw3UZbA9zh

[Onoff]

Could you use a cheap car recharge kit with R-134A gas?

 

(I know nothing btw).

 

Edit: Further reading suggests not!

Edited June 8, 2018 by Onoff

[ProDave]

I have done some more looking around.  What I find is the company that sold this unit to me are no longer selling this particular brand of heat pump (I won't mention the company or make of the heat pump in case it gets messy)  That probably explains it's sale at a low price as selling off stock of a discontinued model.

 

It was sold to me as "new" on 23rd June 2017.  So I am very close to the 1 year guarantee expiring.  Given my lack of reply from the company yesterday, I have now sent an email, and if no response is received on Monday I will follow up with a recorded delivery letter, making it clear I am making a warranty claim to rectify the problem with this unit.

 

I will let you know how it proceeds.

 

Perhaps a cautionary tale about buying cheap bargains in advance of when you are ready for them.  Hopefully the fact I discovered and reported the issue before 1 year was up will be okay.

[Jeremy Harris]

Well worth pushing to get it fixed under warranty, especially as it sounds as if it had lost refrigerant before you received it.  I suspect it has a leak, which means it will need to be vacuumed, held under vacuum to get any moisture out, then refilled and leak tested.  Any refrigeration/air con engineer that holds an F gas ticket can do the job in an hour or so. 

 

The main concern that I'd have is whether a warranty repair might end up being just a re-gas, without a proper leak test.  If there is a leak, then just re-gassing the unit may get it working for a while, until the refrigerant leaks out again after the warranty has expired.

[ProDave]

If it has a leak, I think it is a gross leak as I am 99% sure now it had no gas when I received it, I don't think it has slowly leaked out over the intervening 11 months. So hopefully that wold be obvious on re gassing.

 

I am convinced, for various reasons, that this unit was previously used as some form of in house training or development. If that theory is right, regular de gassing and re gassing might be something they did to it and forgot to fill it again.  Well you can live in hope.

[Onoff]

I'd email them a copy of the letter too. Just say in the covering email you're sending this by recorded mail.

[Jeremy Harris]

You just need to hope that it hasn't got moisture in, as that can seriously bugger up things like valves and the compressor.  With luck it will have been run enough with gas in for some oil to have been circulated around the refrigerant circuit and provide enough corrosion protection.  If the unit has just been left degassed, with just some slight residual pressure, then that should mean it's OK internally.  Fingers crossed that the company can sort it properly.

 

[Nickfromwales]

Will you have any issues with parts becoming obsolete or can you Frankenstein other manufacturers parts in later down the line? 

[ProDave]

1 minute ago, Nickfromwales said:

Will you have any issues with parts becoming obsolete or can you Frankenstein other manufacturers parts in later down the line? 

That is always a worry.  As far as I can tell the refrigeration unit is made by EBAC (that is not the name on the heat pump) but I suspect the controls are not.

[Nickfromwales]

Well, for £500 you can afford to run it until it dies TBH and still not grumble. 

 

[ProDave]

So this is what I have, a re badged EBAC heat pump http://www.pmcoppack.com/products/heat-pumps/ebac-air-source-heat-pump-5kw-suitable-for-up-to-3-bedrooms/0011933.html

 

Just to be clear that is NOT the company I bought mine from, just the first link showing it that I found.  Mine is identical in appearance, dimensions, weight, and specification, it just has a different name on the outside, but EBAC stickers on the inside.  So hopefully it is using EBAC controls just with a slightly customised diagnostic interface just with a different "manufacturer" name shown.  Even their description of the user interface and inbuilt wifi is the same.

 

So hopefully if I need spares, EBAC might be able to support it.

[Jeremy Harris]

Looks to be a Mitsubishi compressor, from the part number, which is good news, as these are pretty common and used in a fairly wide range of heat pumps and air con units.  My guess is that EBAC are assembling these from well-known parts, as they make them here in the UK, and that's also good news, as the chances are that there will be several sources for spares.

[ProDave]

Not so good news, no mention of them on ebac.com, not even the fact they started developing them in 2011. So it looks like they have stopped making them and erased it from even their history.

[newhome]

Hopefully the supplier will sort for you but just a few things to note re your rights:

 

Under the Consumer Rights Act 2015:

• Less than 30 days you can return the goods for a full refund
• Less than 6 months the onus is on the supplier to prove the fault wasn't there when you bought it. The supplier can attempt to have it repaired and if that is unsuccessful they have to refund.
• Over 6 months you are still covered but the onus is on you to prove that it was inherently faulty. So you will need to gather evidence. Photos of the current status of your heating system (ie none) may assist, and gather as much evidence as you can such as where it has been stored since purchase etc. The supplier may require you to get a professional report I guess. Do you still have the receipt, copy of the ad etc? 

How did you pay? If by credit card you may be covered by a Section 75 refund although this shouldn't be your first port of call. 

 

Your warranty will be with the manufacturer I imagine, ie the brand name on the item, so if not one and the same I would contact them pretty swiftly also if it's only for 12 months although there should be an expectation that this sort of item lasts much longer than a year, even if it had been used!  

 

 

[newhome]

Looks like both the brand and the supplier are part of the TP group? Not a tin pot affair by any means so hopefully you will get somewhere with addressing this. 

 

 

[ProDave]

I will keep you posted. Just to be clear the supplier and brand name it was sold under has not yet been mentioned on this thread I don't want that information to inhibit what I may or may not say.

 

I have a copy of the receipt giving the sale date and estimated delivery date and my point of (if necessary) sending a recorded delivery claim was to establish the fact the issue was identified before the 1 year warranty had expired. It was brought from ebay

 

I have just looked and the ebay listing is still there though the pictures have gone. I will take a print our of that in case it goes offline.

 

In the ebay listing is a "full description" link ans when you click that, this little snippet is at the top of the description:

 

• UK Design, UK Manufactured, for the British climate
• Highest quality construction with corrosion protected evaporator coil
• 7 year warranty full parts and labour warranty as standard
• All components wire back to internal auxiliary box, ensuring that internal to external cabling is kept to an absolute minimum

 

I will keep a print out of that in case they start trying to wriggle out of a warranty claim.

 

Sorry the quote has messed up and I can't edit it. [fixed by mod]

[newhome]

Why do you think the warranty is only 12 months if the full description says 7 years? It’s moot anyway as there is an expectation that this sort of item should last much longer than 12 months and evidence of it being sold with a 7 year warranty is good evidence of that (if indeed you need to take further action). Let’s hope it doesn’t come to that.