Replace Combi with Air-Source Heat Pump?

RoyMi6

RoyMi6

RoyMi6

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Just had a meeting with a representative from the company that gave us free roof and room insulation on our 1983 build home (happy with how that went)

They're saying they've that there's a new Renewable Heating Incentive that we're eligible for that would give us £3039pa (£253.25pm) if we had a Air-source heat pump system installed to replace our gas combi boiler.

Included in the installation of the air conditioning unit outside we'd get a hot water tank installed in the loft as well as all the radiators replaced in the house (something that I had been looking at recently!)

They'd also provide 10 years of cover for the installation as well as 4 hour call out - included for free.

The costs would be £15,500 for the install but charged at £199 per month (on finance). With the RHI form the government we'd actually be £54pm better off.

Factoring in the projected cost savings of around £20 a month, compared to gas, it kind of seems like a win win for us (and yes I understand that they're making a tidy profit with these as well)

The idea of going all electric appeals to me (if we get solar panels installed we could live off grid!) but my previous experience with Electric Storage Heaters also showed me how bad it can be.

So, anyone had one installed? Good idea? bad idea? how loud is the air conditioning unit? Will it work in spite of my old house that doesn't have the best insulation in the world?
 
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I get alarm bells, only as I heard a Radio 4 programme a year or two ago about companies pushing these systems and leaving people with cold houses and steep bills. I've tried to find it for you but can't, sorry (might have been You And Yours but nothing coming up). Do your homework!

Maybe others have direct experience.
 
Oh yeah, totally aware of this kind of thing (massive fan of Watchdog :)) but everything he was saying I could find up backed up online (https://www.gov.uk/domestic-renewable-heat-incentive) and I checked in front of him.

I forgot to mention it in the opening post but the contract also has a 14 day cooling off period "from the day the installation is complete". So signing this week wouldn't mean we've only got 14 days to get out of it, but 14 days of running the system to see if it's capable of getting the house to temperature and run efficiently.

Given that we'd be having it installed within 4 weeks of signing it's probably a good time of year to put it through its paces.

If you can find people complaining about the systems themselves that would be good as I can't see anything wrong with their sales tactics or the RHI payments not being legit.
 
Ground/Air heat source pumps systems operate differently from your standard gas boiler, the main difference is that they run at a very low flow temp generally well under 40c (you gas boiler is likely running around 60-70c)

This means they work very well with underfloor heating but when using radiators you need to over size them to allow greater heat output at low flow temps, this is the likely reason they replace them as part of the work.

The system is unable to heat your hot water cylinder to 60c without using an immersion heater and in the winter months an immersion heater is required to boost the central heating side of the system. This has implications as electricity is 3x the cost of gas and you may find the system using a lot during the winter months it would be interesting if they have included this use in the comparison with a gas boiler.

You can't heat your house as you do with a gas boiler the system should be left running for near 24 by 7 at a low temp rather than trying to heat up the house in an hour or so (the system will be unable to this as the flow temps are low) A lot of complaints about these systems come from this as users are expecting the system to operate like a gas boiler system where they come home with the house at 15c and expect it to be up at 20c in an hour or so.

The average efficiently is around 3-4kw of heat given out for 1kw of electricity used this sounds good but you need to take into account if you have mains gas this is a 1/3 to a 1/4 of the price of electricity. Generally speaking unless you have a modern house with very good insulation and you have mains gas with a modern gas boiler with oversized radiators that allow lower flow temps so the boiler can condense for the majority of the running time it will be cheaper to heat your house/hot water with a gas boiler.

You need to carefully work out the sums with the RHI, I personally would work it out on the assumption you are not going to be saving any costs over your gas bill even take into account worse case winter usage could be 10-15% more.

I have a medium sized AC unit used for cooling in the summer and it is fairly noisy you wouldn't want it near a window or on/near your patio.
 
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I've installed and used, Air Source and Ground Source systems... Get ready to be cold.

As above, for a house to use one of these systems effectively it needs to be designed and built with the system in mind imo.
 
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Whats the unit price you get paid on the RHI per kWh for an ASHP? That multipled by your houses' energy requirement on an EPC/SAP is what you'll get paid? How did he come up with £3039???

I've got a Ground source HP, works absolutely great, but it is a new build/barn conversion with UFH throughout. We get about £1200/yr through RHI, so either your house needs a LOT of energy to heat/DHW, or the rate /kWh for an ASHP is a lot more than for a GSHP (doubtful).

Also, £15k for an ASHP+rads seems crazy, an ASHP unit is only a grand or 2 im sure. You need to be absolutely certain about the RHI payments and what your house will cost to heat/DHW before going for it.
 
I've got a an air source heat pump. Every room in the house, Inc conservatry is at 21-22c and running at 300-400% efficiency so far over winter. If it's done right they are absolutely fantastic. Mine replaced a combi boiler. I'm running radiators which are sized to run at 35c flow temp.
 
There was something on the local news ages ago about some company with a "govt" scheme who installed a heat pump in some pensioners home. System turned out to be inadequate and it's now costing them more to heat the house as they are having to put electric heaters on as the heat pump is not providing enough heating.

Also spending £15K to save £20 a month doesn't really sound good value for money, unless you are rich with huge savings to burn.
 
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We've been to a good 50+ houses this year where people have had them installed and the installers haven't had any idea how setup them up. That's the main problem. After sorting their issues everyone's been happy. If done correctly the technology works flawlessly. If you replace a gas boiler with a heat pump your bills should be around 25% cheaper than gas. If replacing electric storage heater you'll save 75%. Figure in the renewable heat incentive payback from the government which lasts for 10 years. Its a amazing deal
 
So had the second visit regarding this last night.

This time it was with a 3rd party who just came in to measure up and inspect the house in general to spec out the system.

Got hold of the original sales guy on the phone to confirm a couple of things.

The RHI we're getting is a "deemed payment" rather than a feed in tariff.

The amount of £3039 per year is worked out beforehand based on our current EPC rating. This amount also goes up with inflation each year.

Some people have said "spending £15K to save £20 a month doesn't seem worth it" but the actual practicalities of it will mean we're £50 per month better off each month because the RHI is more than the install cost (if paid on finance)

In addition we're having our entire system updated and serviced AND we have the potential to save some money on top.

Now... saying that... :)

NPower (our provider) have just said they're upping gas prices by 4.8% and electric by 15% (http://www.bbc.co.uk/news/business-38852517)

It seems annoyingly counter intuitive given Scotland's ability to produce as much electricity as it has done. While we're on a fixed tariff at the moment it won't effect us, but it obviously is concerning for when that comes to an end.

I've also found out that my dad knows the owner of a local company that do these kind of systems, so getting a 2nd opinion from him as well.
 
LAAAAAAAAAAAAAAAAWLS!

So!

My parents phoned them up to see if this "deal" was still going on. They told them they've gone into liquidation!

Checking online it appears the company is still obligated to find a company to continue all repairs and inspection for the next 10 years - http://www.energysavingtrust.org.uk/scotland/grants-loans/green-deal

It does appear that everything they sold (while not a viable business opportunity) was genuine, and actually a good deal - but just to a detriment to the company!

In addition, as the RHI payments are done by the government no one has lost out on that money coming in to pay for this installations.

Bullet dodged or opportunity missed?
 
Yes, a large heat pump installation company just went under. We've had a few people ring us about it to see if we can finish or do their work. It's definitely worth looking for another installer because the rhi payments providing they worked them out right, will be the same. (Btw rhi is going up to 10p per kWh in April x7 years) I can put some pics up when I get back of my install so you can see what's involved if you like.
 
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