Sensible ASHP quote?

simons_s

Hi

A neighbour of mine had an ASHP installed about 6 months ago along with some solar panels. So far he's impressed with the results and apparently it's slashed his heating bills (although he hasn't gone through a full winter with it yet). Our houses are very similar (his slightly larger) so I had a survey done by the same company that installed theirs, to replace our LPG boiler.

During the survey all rooms where measured and it was concluded we would need four additional radiators installed. He didn't ask about loft insulation, cavity insulation or check for draughts though.

From what I've read so far I think the quote is on the high end of an ASHP installation, but the property is a 4 bed detached so it might be reasonable:

12 KW NIBE Air Source Unit Heat Pump - 1
NIBE Indoor unit - 1
250L Cylinder & 100L Buffer - 1
NIBE F2040 Control Unit - 1
Expansion Vessel - 1
K2 Radiators - 4
£10,584.00

Some basic calculations included in the survey:
Heat pump running costs £ 521.05
Alternative heating system (LPG) £ 1,173.91
Annual saving £ 652.86

Renewable heat incentive rate (payable for 7 years) £ 1,326.32
Annual Financial benefit ( accumulation above) £ 1,979.18
Return On Investment (ROI) 19%

At the same time I also asked to be quoted for installation of some solar panels to help with running costs of the ASHP. I've been quoted for a 4KW system consisting of 16 Perlight Solar 250W panels costing £4,905.

The annual savings sound optimistic to me and if these numbers are correct the savings and RHI could end up almost paying for the job in the 7 years.

I very much like the idea of a constant heat in the house. Our LPG bills aren't that high but we're often cold in the house as our bills would get crazy expensive having the heating on all day. We're also connected to a shared LPG tank so switching is a pain.

This would be a very big investment for me so I wanted to get some opinions of what I've been quoted and perhaps some things I should be looking out for? Any first hand experience of NIBE?

Thanks!

Martyn1981

Hiya. Not what you're asking, but a small contribution, the PV quote is decent, £5k for 4kWp is a good price, but do you have room for more if you are an all leccy house (thinking of becoming)? At the very least perhaps consider 280Wp+ panels as these won't impact any other costs but will lift output for a small premium on the panels, which are relatively cheap anyway.

Not comparable to what you are doing, but I had a small ASHP (air con) installed in April, just a 3.5kW unit to heat the living room and avoid GCH. Cost was approx £1k installed

So far this year the GCH hasn't been on since the install, and most of the heating has come from PV supply. I've been running the unit during the day with living room door wide open to 'store' as much heat as possible during the day.

I assume you'll be able to do similar, even with a larger wet system turned down low, from Feb onwards, and till Nov, if you have a decent (4-6kWp) PV system. Then a nightime E7 boost (?) during the night perhaps. Though of course the winter contribution from spare PV will be much lower, and COPs too.

simons_s

Hi Martyn.

I don't believe we have room for more as during the survey he said it the house would fit 8 on the front and 8 on the rear. That's good info on the panels, thanks. I will ask the question and see how much it increases the cost.

Cardew

It might be worthwhile doing some research on NIBE ASHP systems - on this forum and elsewhere.(there was a Facebook page) In particular check the warranty.

Lots of people had troubles with their system; albeit that was some years ago and it might now be resolved.

[Deleted User]

Cardew wrote: »

It might be worthwhile doing some research on NIBE ASHP systems - on this forum and elsewhere.(there was a Facebook page) In particular check the warranty.

Lots of people had troubles with their system; albeit that was some years ago and it might now be resolved.

Mitsubishi [that's what I have - trouble free after six years...], Dimplex, Panasonic, Daikin all brilliant. Nibe, hmm....


Solar panels nice to have and a great addition but will do little when you really need the heating. Divert to hot water, leccy car etc


Your proposed electric bills look a bit optimistic, especially with regular rads. Perhaps your house is modern and well insulated? Mine 100+ years old large detached ~£80pm total electric with 4kWh Solar.


Personally I wouldn't hang rads [as they would be massive for low flow temps] off an ASHP bar UFH downstairs/rads upstairs. I hope also that your existing rad pipes are all the right bore + insulated for high flow/low temps? We have a mix of fancoils/UFH/Bathroom towel rail so have a good idea how all work. The fancoils are superb and the best compromise IMHO.


Tip - go for Honeywell diverter/actuator valves - waaay the best. Danfoss ok as cheap to replace.


Sadly I'm moving house so loosing all the RHI & FITs. On the upside the new super insulated house will barely need heated


Marts setup is also a great idea


Cheers

simons_s

@Cardew

I'm struggling to find much about NIBE when I google them. I did see some negative things written here about them but it was mostly for older units and not the new f2040-12. I actually haven't seen anyone say anything good about them either. The energy company I had come and do the survey did not give me any manufacturers to choose from which leads me to believe they're only qualified to fit NIBE's, and I did see a post on this forum which said NIBE hands out certified installer certificates to just about anyone.

Apparently the warranty is also void unless I get an annual service done, which costs £145. In their defence this was clearly stated on the survey I had done.

@jeepjunkie

The house is about 20~ years old. Insulation is not terrible but not great either. I'm planning on improving the loft insulation and lining our attached garage with celotex boards. AFAIK we have cavity wall insulation due to the property age. Double glazing is still the original.

I don't know if retrofitting UFH is an option for us. Even overlaying would mean raising skirting and replacing floors in the kitchen / toilets. I would imagine this is quite expensive and not something that was mentioned in the survey.

I don't know about the bore & insulation of the pipes. Also not mentioned as an issue in the survey. Any way I can easily check myself?

I have another company coming out next week to quote for the same job. I will ask him the questions about upgrading solar panels, UFH, pipe bore size / insulation etc..

Thanks!

lovesgshp

It is not always required to change radiators or pipework. Many systems here in Italy are working on original rads with no problem.
I do not know much about Nibe, but have seen they have had quite a few problems. Research all the pumps very well before you make a decision, as the COP can vary by quite a lot.

simons_s

@jeepjunkie what mitsubishi heat pump do you have?

I had a second installer here today who mostly fit mitsubishi heat pumps and has recommended the mitsubishi ecodan 8.5kw. I'm trying to research this model now and it does seem to be more popular than the nibe. Has anyone got any first hand experience with this model?

How do I know who is trying to sell me the correct size heat pump?

The two models recommended by these installers are quite different in size. The second installer already told me what heat pump he would install without taking any measurements (he did go on to measure all rooms and window sizes). He hasn't given me any quotes yet but did say I wouldn't have to upgrade many radiators, just the singles to doubles. The first installer wanted to upgrade the one double radiator in the living room to a much larger one and add a second one.

The second installer also recommended I not fit solar panels onto the property. He told me the house is not at a good position for solar panels and the nearby trees would affect performance.

The mitsubishi also only has 3 years standard warranty, where the nibe has 7 as standard.

I'll wait for the quote from the second installer, but to me if they're similar in price it would make sense to go for the nibe as it's a larger unit with a longer warranty?

edit: if 'the calculation' at the bottom of this page is anywhere near correct I wouldn't of thought the 8.5kw would be enough.

House is 132 meters squared according to the EPC
House is not refurbished so anything between 70kw and 100kw lost
(70 * 132) / 1000 = 9.24
(100 * 132) / 1000 = 13.2

Cardew

jeepjunkie has an Ecodan; as have other posters on this forum.

I suggest you do a forum search for Mitsubishi Ecodan and you will find loads of posts.

I think you will find that there is little criticism of the Ecodan, but plenty of criticism of the installers. Unless your system is properly installed it can be a disaster.

You might be interested in reading the Energy Saving Trust's report on trials of heat pumps - links on this forum. You will see the huge difference in the COP of systems.

simons_s

Thanks for the info I do appreciate it. Unfortunately UFH won't an option for us due to our budget, and we want to move away from LPG/Oil and having fuel deliveries.

The second company quoted £8900 for the pump and installation, and recommended radiator upgrades costing £1600.

8.5kW Mitsubishi Ecodan Kit
Mitsubish Ecodan PUHZ-W85VHA2 8.5kW ASHP Outdoor Unit
FTC 5 Controller
Fix-it foot 600 Vibration Proof Base
Expansion Vessel with robokit
Circulating Pump(s)
High Performance In-Line System Filter
Thermox DTX Glycol
Plumbing Pipe and Fittings
Ancillaries
Delivery
£4,413.30

Unvented Hot Water Cylinder 200L Single HP Coil
£888.55

Low Loss Header
£300.00

The remaining cost comes from installation, commissioning, EPC etc..

Interestingly, the second company mentioned the radiator upgrades are only recommendations and that 'I may find the current system can perform to my requirements'. That doesn't exactly fill me with confidence.

When taking into account radiator upgrades that have been recommended the two companies quotes are very similar in price.

All things considered I believe the Nibe is better value, and has a much longer warranty. The first company are also charging half the cost per radiator installation.

Still so confused with it all - need to do more research.

Cardew

simons_s wrote: »

Still so confused with it all - need to do more research.

As I stated in post#10

You might be interested in reading the Energy Saving Trust's report on trials of heat pumps - links on this forum. You will see the huge difference in the COP of systems.

There is no doubt that Mitsubishi and other manufacturers produce good equipment.

The problem is that these manufacturers do not take responsibility for their equipment working to the specification they indicate in their brochures i.e. COP xx @ yy outside temperature. They sell their equipment to installers, and they fit the equipment.

This is particularly so in retrofit installations. The problem we have as consumers is we have no guarantee of performance. If you look at the 12 month trials carried out by EST some installations were little short of a disaster. System COP's as low as 1.2 and under 2.0 was not unusual.

The equipment needed to measure system COP is simply not available to customers. Even if you can monitor electricity consumption to the ASHP how do you measure heat output? Put simply you have no comeback if your system performs poorly.

No installer is going to refuse to fit a system in an unsuitable house. e.g. unsuitable radiators, pipes for flow rate etc.

Essentially you need to research the installer, more than the equipment and hope he is competent and honest.