Air source heat pump

tamzzy

tamzzy

tamzzy

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Talk to me about air source heat pumps
At 8p/kwh electricity + solar PV, it seems a no-brainer

However I've got a very new boiler about 2 years old and I don't wish to remove this just yet

With the Boiler Upgrade Scheme grant, do I have to remove this boiler or can I use the grant to install a ASHP system that runs alongside the boiler (ie a "hybrid" system)?
 
tamzzy said:
Talk to me about air source heat pumps
At 8p/kwh electricity + solar PV, it seems a no-brainer

However I've got a very new boiler about 2 years old and I don't wish to remove this just yet

With the Boiler Upgrade Scheme grant, do I have to remove this boiler or can I use the grant to install a ASHP system that runs alongside the boiler (ie a "hybrid" system)?
Click to expand...

Yes your boiler has to be ripped out to be eligible for the grant.

200sols said:
Don't count on solar, when you need the heating its rarely pumping unless you have an absolutely huge array. Also you won't be getting 8p all day.
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Not sure I agree about that. My array is big but it’s not that big and I have 13.5kwh battery which again is big but not that big and I’ve not come close to touching peak time electricity yet on IOG.

Sure you are not going to be doing a huge amount of solar over winter but combined with grid charging batteries it makes a significant difference to running costs.

Heat pumps have a slightly lower running cost than gas when buying at the price cap.

The battery means you can take proper advantage of time of use tariffs like cost, agile and IOG to massively reduce the average cost of energy compared to the price cap so there is real money to be saved.

Even though if I couldn’t get through an 18 hour gap on IOG during the depths of winter, the triple dip @12p on Cosy would never be an issue.

tamzzy said:
it's 7 hours from 0000-0659, is that enough time to heat the tank?
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More than, my 180L tank takes 35-40mins.

P.S. There is a 40 page thread on heat pumps in this sub forum already.
 
tamzzy said:
Talk to me about air source heat pumps
At 8p/kwh electricity + solar PV, it seems a no-brainer

However I've got a very new boiler about 2 years old and I don't wish to remove this just yet

With the Boiler Upgrade Scheme grant, do I have to remove this boiler or can I use the grant to install a ASHP system that runs alongside the boiler (ie a "hybrid" system)?
Click to expand...


They are a good idea, but whether you make money on them very much depends on the house you are living in.

The main cost is not the heat pump itself. Rather it is modifications to your existing central heating, insulation and maintenance costs.

93% of installations require significant changes to, or complete replacement of the central heating system, and additional home insulation.

The first thing I would do is get some real quotes, before you get too wrapped up in the idea, and do the calculations to see if you will actually make money.
 
SpellowHouse said:
The main cost is not the heat pump itself. Rather it is modifications to your existing central heating, insulation and maintenance costs.

93% of installations require significant changes to, or complete replacement of the central heating system, and additional home insulation.
Click to expand...
Thank you, just had my home refurb a couple years ago, added in internal insulated plasterboard to the external-facing walls.
My current boiler runs at 50c flow temp (so similar temps to a heat-pump).
All piping and radiators are new as well and function well with 50c flow temp so I don't anticipate any of them needing replacement.
Fwiw my gas bill during Dec/Jan/Feb this year was £60/mth on average.

Having slept over it maybe the cost/benefit isn't that much to warrant throwing away a 2 year old high-end boiler currently.
 
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if you are running on a 50C flow temp then in theory, you are heat pump ready already bar the heat pump itself and probably a cylinder swap to one with a larger coil.

On the insulation point, you just can’t have any loft insulation recommendations on your EPC, if you have 300mm, it’s fine.

You’ll not ‘make money’ but you might want to consider that given how little work you actually need to do, the government grant is likely to cover the cost of the entire installation. You might be left with a token £500 to pay. You might get £500 back over the lifetime of the appliance but there is no ‘ROI’ like solar. Just don’t forget the tons of carbon savings per year.

The government grant isn’t going to get more generous (IMO) so you might as well take advantage while you can.

I’m not sure why you’d wan’t to keep your existing boiler, it would be completely redundant.

You could sell the boiler once it has been decommissioned, it is yours at the end of the day.
 
Best thing to do is get a quote.

My 2 bed mid-terrace was quoted £860.00 for the 4KW HP install. Adding the extras required by law has bumped this to ~£1300.

Opposite 3 bed end terrace applied after me. Similar £860.00 quote for a 6KW HP. However Octopus have added an additional £250 discount and one less paperwork step means his is coming to ~£1100.00
 
SpellowHouse said:
The main cost is not the heat pump itself. Rather it is modifications to your existing central heating, insulation and maintenance costs
Click to expand...

This. Gas boilers can put out hot water at 80C no problem. Heat pumps usually only manage 40-50C, which means for the equivalent amount of heating you need to have it working for twice as long as your boiler would have been, and have twice the surface area of radiators in the house. That's just one of the many reasons for modification. Gets very expensive very quickly.

When I looked into it, I realised spending the money on more solar capacity (if you have space) and more battery capacity was a better use of the money.
 
b0rn2sk8 said:
You’ll not ‘make money’ but you might want to consider that given how little work you actually need to do, the government grant is likely to cover the cost of the entire installation. You might be left with a token £500 to pay. You might get £500 back over the lifetime of the appliance but there is no ‘ROI’ like solar. Just don’t forget the tons of carbon savings per year.
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Yeah, I considered it as savings per year rather than actually earning money as with the solar PV
 
Ormy1 said:
This. Gas boilers can put out hot water at 80C no problem. Heat pumps usually only manage 40-50C, which means for the equivalent amount of heating you need to have it working for twice as long as your boiler would have been, and have twice the surface area of radiators in the house. That's just one of the many reasons for modification. Gets very expensive very quickly.
Click to expand...
True. In my case though my boiler is already running at 50c for max efficiency so it's the same as an ASHP
 
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