New air source heat pump Qs

[NoNameNoNumber]

Evening all,

We're going to replace our aging oil boiler for an ASHP.
We have 6.7kW of solar PV and a 5.12kW/hr battery so it makes sense. I've gotten rid of all of the downstairs rads and having the flooring machined by JK flooring for a wet UFH.

I've received a number of quotes, all around the £7-7.5k mark with the BUS, after a little research I've ruled out any of the Samsung/LG units. Been looking at Daikin and Steibel Eltron.

When we had the PV done I was advised to look out for HEIS, MCS and Napit. Now who is the equivalent for ASHPs?

What assurances can I expect that we will be able to maintain >20ºC all winter and my COP will be >400% as per the manual?

Do I pay the installers £15k then claim the BUS myself or do they do all of that and I just pay out the £7.5k?

At the same time I want them to upgrade my inverter from 3.6kW to 5kW and sort the DNO (which a number of companies have offered to do) but they use the flexi orb cert. Will this have any effect on my export tariff and SEG with Octopus?

I'm sure there will be more...

Kind regards

 

[PermaChanged]

is the equivalent for ASHPs?

What assurances can I expect that we will be able to maintain >20ºC all winter and my COP will be >400% as per the manual?

Check out HeatGeek registered installers.

 

[fish]

Check out HeatGeek registered installers.

However they may mess you around for 5 months and not get back to you and lose your information multiple times. Until eventually you have had enough going through multiple complaints procedures and they refund you. But your mileage may vary.

 

[Skilid]

However they may mess you around for 5 months and not get back to you and lose your information multiple times. Until eventually you have had enough going through multiple complaints procedures and they refund you. But your mileage may vary.

You don't have to get a quote through Heat Geek. You can find your nearest qualified installer and get a quote directly from them.

@NoNameNoNumber Do I pay the installers £15k then claim the BUS myself or do they do all of that and I just pay out the £7.5k?

Installers claim it. Nothing for you to do.

 

[PermaChanged]

However they may mess you around for 5 months and not get back to you and lose your information multiple times. Until eventually you have had enough going through multiple complaints procedures and they refund you. But your mileage may vary.

Ouch!

Seems my heat pump installation issues are not isolated to the non-Heat Geek affiliated installer I chose. Although, I still wish I had chosen a Heat Geek qualified engineer rather than the muppets I did deal with!

 

[gazref]

Last I checked HG offered assurance on efficiency/performance of the system. If so by extension theyd be vouching for the design of the total heating system. Something to factor

 

[shroomz]

Last I checked HG offered assurance on efficiency/performance of the system. If so by extension theyd be vouching for the design of the total heating system. Something to factor

But the heat geek guarantee seems to come with additional cost, would the cost benefit be worth the risk?

Evening all,

We're going to replace our aging oil boiler for an ASHP.
We have 6.7kW of solar PV and a 5.12kW/hr battery so it makes sense. I've gotten rid of all of the downstairs rads and having the flooring machined by JK flooring for a wet UFH.

I've received a number of quotes, all around the £7-7.5k mark with the BUS, after a little research I've ruled out any of the Samsung/LG units. Been looking at Daikin and Steibel Eltron.

When we had the PV done I was advised to look out for HEIS, MCS and Napit. Now who is the equivalent for ASHPs?

What assurances can I expect that we will be able to maintain >20ºC all winter and my COP will be >400% as per the manual?

Do I pay the installers £15k then claim the BUS myself or do they do all of that and I just pay out the £7.5k?

At the same time I want them to upgrade my inverter from 3.6kW to 5kW and sort the DNO (which a number of companies have offered to do) but they use the flexi orb cert. Will this have any effect on my export tariff and SEG with Octopus?

I'm sure there will be more...

Kind regards

I'm looking at heat pump installation as well, unfortunately there don't seem to be many heat geeks up this way. I've been gone for the Energy Saving Trust (home energy Scotland) grant and loan for mine, which also has a pv+batteries bit.
MCS seems to be the only requirement for the grant I'm going for.
I'm looking to share experiences on both as well, happy if I partly hijack your thread?

 

[BUDFORCE]

they use the flexi orb cert. Will this have any effect on my export tariff and SEG with Octopus?

I can't answer any other part of your post.

Our solar install is flexiorb, it's just an alternative to MCS.

In some ways slightly easier because your DNO approval is registered through them so you don't get the DNO certificate as such - so don't panic if you don't get it yourself.

Octopus are fine with it now, although that's only been the case for maybe 6 months and it does restrict what suppliers you can use for SEG a bit, as less accept Flexiorb.

We are with Scottish Power for export at 12p p/kWh but father in law who also has Flexiorb solar is with Octopus.

Scottish Power are a ******* nightmare to set up though, so probably best to stick with Octopus, even though for us they didn't pay as much.

 

[dirtychinchilla]

You aren't going to get an SCOP of 4. You might get somewhere near that, but it varies completely with the seasons.

 

[shroomz]

You aren't going to get an SCOP of 4. You might get somewhere near that, but it varies completely with the seasons.

Why do you say that? Heat geek do guarantee a minimum of 3.9. Also what about the heat pump monitor?

HeatpumpMonitor.org

heatpumpmonitor.org

 

[b0rn2sk8]

You aren't going to get an SCOP of 4. You might get somewhere near that, but it varies completely with the seasons.

SCOP = seasonal aka annual measure.
COP = here and now measure that varies with the seasons.

SCOP of 4 is very doable, particularly with underfloor heating.

Evening all,

We're going to replace our aging oil boiler for an ASHP.
We have 6.7kW of solar PV and a 5.12kW/hr battery so it makes sense.

It does but in reality that battery is fairly small and a heat pump will rinse that in a few hours when it’s very cold.

If you have a time of use tariff you’ll want to charge it whenever it’s cheap.

I've gotten rid of all of the downstairs rads and having the flooring machined by JK flooring for a wet UFH.

Make sure they have done the heat loss correctly and have calculated the UFH spacing correctly for low temperature and your floor covering.

I've received a number of quotes, all around the £7-7.5k mark with the BUS, after a little research I've ruled out any of the Samsung/LG units. Been looking at Daikin and Steibel Eltron.

From what I understand Vaillent is currently considered to be the best but Daikin is also fine (mines Daikin). I’ve not heard of Steibel.

When we had the PV done I was advised to look out for HEIS, MCS and Napit. Now who is the equivalent for ASHPs?

HIES is an insurance scheme for your deposit/extended warranty, it doesn’t impact you using the product. Others exist but it doesn’t really impact the installation if you are using someone reputable and has been around for a long time.

Napit is an electricians professional body and runs one of the celery certification for building regs schemes. Don’t worry about it.

MCS is the renewables/low carbon scheme. I think you’ll want an MCS installer to do it to make sure you’ve got the relevant paperwork if you want to sell but it doesn’t stop you not using a non-MCS installer. There isn’t an export scheme to sign up to like solar.

I’d have serious doubts if a heat pump installer wasn’t MCS (or equivalent) or operating under an MCS umbrella like say via heat geek. You do need to know what you are doing.

What assurances can I expect that we will be able to maintain >20ºC all winter and my COP will be >400% as per the manual?

The design temperature should tell you this, there are look up tables in the heat pump manual for a given power and flow temperature. Basically the lower you go on flow temperature (and therefore the bigger rads/closer UFH spacing) the higher the COP for your heat loss. 400% is doable but will be more expensive than one targeting 350%.

Do I pay the installers £15k then claim the BUS myself or do they do all of that and I just pay out the £7.5k?

They do it.

At the same time I want them to upgrade my inverter from 3.6kW to 5kW and sort the DNO (which a number of companies have offered to do) but they use the flexi orb cert. Will this have any effect on my export tariff and SEG with Octopus?

Flexi orb is now as widely accepted but Octopus accept it.

I'm sure there will be more...

Kind regards

Ask away, I had mine done a few weeks ago. It’s early days but seems to be working well.

 

[NoNameNoNumber]

Thank you all for your replies, and apologies for the delay, we bought a new-born home last week so it's been a little busy here...

We've had several quotes back now and have a technical survey with Aira next week.
They offer a 10 year performance guarantee, 10 year product and installation guarantee and a 2 year insurance backed by HIES
The 12kW Vailiant Arotherm @ 45ºC flow temp SCOP is 4.21. I'd like to see in writing that figure being backed by their performance guarantee.

 

[b0rn2sk8]

Vailant is good kit and the flow temp looks sensible for a retrofit. Dare I ask how much?

 

[NoNameNoNumber]

£7500 after the BUS
That includes a 250l tank and 5 new rads
Also, a 5kW solar inverter (long story)

Aira are bringing their own ASHP to the market, think he said the 6kW and 8kW are out now but the bigger ones are due Sep. They have a 15yr warranty, and a SCOP of 4.7 @35ºC which isn't as groundbreaking as their sales guy tried to convey. They do only make 57dB though, and the warranty is good. He did say they're based on the Arotherm.

The Aira Heat Pump Outdoor Unit | Aira

The Aira Outdoor Unit efficiently draws in and extracts thermal energy from the fresh air outside to heat your home and hot water.

www.airahome.com

 

[b0rn2sk8]

This is well worth a watch for anyone interested in buying a heat pump or are buying a house with a heat pump.

They pulled their punches in the video but these are absolute dog **** installs.

TLDW:

• Brand new high end development with houses built to the near passive house standard with very low heat loss.
• The workmanship looked reasonable on the physical install but the design is just bonkers.
• The ground floor is entirely open plan and yet has 4 thermostats to control it which is just bonkers as the space is always going to be the same temperature throughout.
• The underfloor heating had a high temperature blending valve (which lowers efficiency) despite being a low temperature system
• The install has separate heating circuits for upstairs and downstairs with a loss loss header and additional pumps which costs more to install and just lowers efficiency - the whole install just needs a single pump.
• The expansion vessel was installed on the flow rather than the return which causes issues in all systems, not just a heat pump - it should be on the low pressure side (return).
• The filter was also installed on the flow which has the effect of protecting the radiators from debris the heat pump may throw rather than what you actually want is to protect the expensive heat pump from crud in the radiators - it should be on the return
• when installed they set it to work with a fixed 45 degree flow temperature which results in a heat pump which just cycles like crazy - bonkers
• Finally the best one - they installed an 11kw heat pump on a property which they calculated to have a heat loss of 3kw which adds a petrol bomb to the cycling issue.
• All of this resulted in a system with a SCOP of 2

This house should be dead easy to heat with a heat pump and should achieve fantastic efficiency. A massively oversized heat pump, with a property which is over zoned and additional equipment which isn't needed has basically resulted in a system which doesn't work.

One of the other houses they installed an 8kw heat pump on a small mid terrace built to a near passive house standard - they didn't run a heat loss calculation but based on the other much larger property, it was probably under 2kw. Absolutely nuts.

It's like they hadn't thought about it at all and just installed it like its an old school gas boiler.