Kingspan ASHP replacment

[Ivon]

Hi all, first time poster here.

 

We have a new build that is fitted with a Kingspan ASHP to a Kingspan cylinder.

 

The system is only 5 years only and due to poor install has never worked correctly. We are on a development of 14 houses and all of them have had problems, some having 3 heat pumps in 5 years and one replacing the Kingspan for another brand after Kingspan pulled out of the market.

 

Our compressor has failed, to be fair, we have had two extensions over the last 5 years so it was well undersized but that leaves us at a loss of what to replace it with.

 

Following the last extension I plumbed in pipework and electrical cables for a Grant oil fired boiler but I just want to make sure we are doing the right thing.

 

Are there any ASHP's that we can directly replace the outside unit with? 

 

We have a 150l indirect cylinder, I know this is small but we only have 3 in the household and use the immersion when we have guests and need to. The system is controlled using Danfoss control units in the airing cupboard, upstairs and downstairs and is linked to a Grundfoss pump. 

 

Any help would be appreciated before we replace the outside unit with oil, once we ironed out issues with the system it eventually ran ok.

 

Thanks.

[Guest Alphonsox]

Hi Ivon and welcome to the forum.

 

If you eventually got the system running correctly would replacing the compressor be a better move than stripping the whole thing out ? Kingspan never actually made heat pumps, they just badge engeneered units made by Carrier ( a huge American air conditioning and other outfit) in Italy. A number of us have these units with different badges on the front covers. Carrier are very much in operation and will probably be able to offer spares to get you up and running again.

 

That being said it may be that the unit was incorrectly sized for your house - not uncommon unfortunately. Could you tell us a bit about it - size, when built, by whom, insulation spec if possible. Could you also let us know a bit more about the outside unit - model number if possible, picture would be good as well

 

There are a number of new-old-stock units that regularly appear on eBay. It may be that buying a bigger Kingspan/Carrier unit might be a solution if you haven't beeen put off ASHPs for life

[Ivon]

18 minutes ago, Alphonsox said:

Hi Ivon and welcome to the forum.

 

If you eventually got the system running correctly would replacing the compressor be a better move than stripping the whole thing out ? Kingspan never actually made heat pumps, they just badge engeneered units made by Carrier ( a huge American air conditioning and other outfit) in Italy. A number of us have these units with different badges on the front covers. Carrier are very much in operation and will probably be able to offer spares to get you up and running again.

 

That being said it may be that the unit was incorrectly sized for your house - not uncommon unfortunately. Could you tell us a bit about it - size, when built, by whom, insulation spec if possible. Could you also let us know a bit more about the outside unit - model number if possible, picture would be good as well

 

There are a number of new-old-stock units that regularly appear on eBay. It may be that buying a bigger Kingspan/Carrier unit might be a solution if you haven't beeen put off ASHPs for life

Thanks for the reply.

 

The house has gone from around 870 sq feet to around 1400 sq feet.

 

One extension is an orangery with a full length glass rooflight, and the second is a cart lodge style with far more insulation than is needed due to the proximity of a railway line.

 

The downstairs is fitted with an air conditioning unit and a stove.

 

We where not that cold last winter, the heat pump hardly worked due to low refrigerant. This was fixed by a friend who's an air con engineer and he adviced the compressor had been damaged due to low refrigerant. It had been topped up about a year before due to constantly defrosting that was put down to a leak. 

 

As the unit is massively underrated now I don't think it's worth trying to rectify the faults.

 

I had been bidding on the eBay listing for the 2 x 8 kw heat pumps but as the price went for the cost of an oil boiler didn't go any higher. 

 

We have a gas hob, I didn't get on with electric.

[PeterW]

Welcome ....

 

Questions : 

 

- what are you using as heating ..? UFH or rads..?

- who programmed the ASHP ...?

- how handy are you..??

 

if you can answer those it's probably a bit easier to advise on replacement. 

[Jeremy Harris]

Welcome Ivon.

 

I strongly suspect that the problems are as you say, poor installation and clueless setting up by Kingspan.  The default settings on these units are hopeless for the UK climate, but the units themselves are very good indeed, when properly installed and set up.

 

I have an identical unit, badged Glowworm, and it took a fair bit of work to get it set up properly.  Both Kingspan and Glowworm had near-zero technical understanding of the Carrier ASHPs they were buying in, and consequently both pulled out of the market after a number of problems they incurred.

 

The major failing is that, by default, these units are set with a barking mad weather compensation curve, and a hot water capability that simply doesn't work well in the UK climate.  The default settings mean that the ASHP will go into defrost mode two or three times an hour, with the compressor and 4 way valve working overtime to try and keep the thing running.  If set up correctly, and if set to not produce very hot water, they are fine, very quiet, efficient and reliable.  If set to try and deliver hot water at 55 deg C (the default DHW setting) the efficiency will be dire, and the unit will run flat out for long periods to try and get that hot.

 

In general, most single stage monoblock ASHPs like this don't work very well when trying to deliver hot water, they work far better when only delivering lower flow tempratures.

Edited September 7, 2017 by JSHarris

[Ivon]

22 minutes ago, PeterW said:

Welcome ....

 

Questions : 

 

- what are you using as heating ..? UFH or rads..?

- who programmed the ASHP ...?

- how handy are you..??

 

if you can answer those it's probably a bit easier to advise on replacement. 

The ASHP is linked to rads.

 

The heat pump was set to the factory setting, it did not come with the Kingspan programmable controller, only the Danfoss timer, so it wasn't possible to change the heat curves. I didn't know about this until I came across this forum the other day.

 

I'm a chemical engineer, in the water treatment industry, in charge of running the UKs only large scale desalination plant. I helped to build both extensions and have a fair amount of practical skills but electrics isn't really my thing. I could swap out like for like but would have to get my Aircon friend to help with more than that from the control side.

Edited September 7, 2017 by Ivon
Added info.

[Ivon]

17 hours ago, JSHarris said:

Welcome Ivon.

 

I strongly suspect that the problems are as you say, poor installation and clueless setting up by Kingspan.  The default settings on these units are hopeless for the UK climate, but the units themselves are very good indeed, when properly installed and set up.

 

I have an identical unit, badged Glowworm, and it took a fair bit of work to get it set up properly.  Both Kingspan and Glowworm had near-zero technical understanding of the Carrier ASHPs they were buying in, and consequently both pulled out of the market after a number of problems they incurred.

 

The major failing is that, by default, these units are set with a barking mad weather compensation curve, and a hot water capability that simply doesn't work well in the UK climate.  The default settings mean that the ASHP will go into defrost mode two or three times an hour, with the compressor and 4 way valve working overtime to try and keep the thing running.  If set up correctly, and if set to not produce very hot water, they are fine, very quiet, efficient and reliable.  If set to try and deliver hot water at 55 deg C (the default DHW setting) the efficiency will be dire, and the unit will run flat out for long periods to try and get that hot.

 

In general, most single stage monoblock ASHPs like this don't work very well when trying to deliver hot water, they work far better when only delivering lower flow tempratures.

You're correct, Kingspan and the fitting company didn't have a clue. 

 

They totally messed up all of the installs, fitted pumps incorrectly, incorrectly wired up units. You name it, they did it. It was their first install of ASHPs, and their last....

[PeterW]

Right so your issue is there - heat curves will be rubbish and the temperature for rads is just too high for standard sized ones. 

 

The Grant oil boiler will tick all the boxes however you may want to be careful as they prefer a long burn so the tank controls may need to be tweaked. 

 

If you keep the rads then it will mean living with lower heat pump performance or going with oil - I would probably go with the latter. 

[Ivon]

Thanks Peter. The rads don't seem overly large, and the rads I have fitted in both extensions are sized to the rooms for an oil/gas boiler, though the ones in the orangery are fed from the upstairs circuit in 10mm pipe so may never balance correctly. I left that to someone else while I was away and only found out this year (that extension was completed 3 years ago). 

 

At the moment I'm leaning towards the oil as I think ASHPs only have a potential life span of 5-10 years. A Grant boiler should last 15-20 years at least and you're much more likely to be able to get spares. 

[Alexphd1]

I was also bidding on the 2x ashp's on ebay, never got it either.

[Ivon]

10 minutes ago, Alexphd1 said:

I was also bidding on the 2x ashp's on ebay, never got it either.

You may well see one of them come up for sale, though I planned to keep both of them, one for spares.

I'm calling it a close call, think I would have regretted it but was the easiest option as it would have been a direct swap for my knackered unit.