Air-source heat pumps - are they good/crap?
Discussion
From the news recently: https://news.stv.tv/north/tomintoul-government-fun...
Yes council mandarins have fitted air source heat pumps to houses in one of the coldest and most inhospitable places in the UK.
Yes council mandarins have fitted air source heat pumps to houses in one of the coldest and most inhospitable places in the UK.
Olivera said:
From the news recently: https://news.stv.tv/north/tomintoul-government-fun...
Yes council mandarins have fitted air source heat pumps to houses in one of the coldest and most inhospitable places in the UK.
Reads like there's some issues with workmanship and billing.Yes council mandarins have fitted air source heat pumps to houses in one of the coldest and most inhospitable places in the UK.
I find it hard to believe a heatpump is working at all if a modern building is getting down to single digits overnight, so clearly there's an issue there.
Would be interesting to see what the ventilation solution is for those homes, whether there's MVHR or PIV.
-Ad- said:
caziques said:
This is the issue, correct installation.
Unlike a boiler, which can basically be chucked in and it will work OK, other factors such as water flow. controls, sizing, defrosting cycles, pipe sizing, radiator sizing and buffer tanks must be considered when a heat pump is fitted.
It would be very unlikely that a heat pump will perform OK simply by replacing a gas boiler.
Essentially this. A Heat Pump requires a heating engineer to do the work on calculating heat loss and then fully designing the system like you say, especially when it comes down to pipe sizing, flow rates, rads etc. Unlike a boiler, which can basically be chucked in and it will work OK, other factors such as water flow. controls, sizing, defrosting cycles, pipe sizing, radiator sizing and buffer tanks must be considered when a heat pump is fitted.
It would be very unlikely that a heat pump will perform OK simply by replacing a gas boiler.
I don't understand why people bang the insulation drum soo much, a house with a gas boiler will still have the same heat loss if you put in an ASHP. Doesn't matter if your place loses 15kW at DOT or 5kW, gas or ASHP still have to work with the same fabric and heat loss.
I'm researching and considering one at some point, but it would be with a pucker company and I'd do all the calcs first to be sure I can check their work and design. But a good one will charge more, especially if you go for Heat Geek assured.
Edited by -Ad- on Monday 5th February 08:33
Pray tell how one does a heat loss calc accurately, even remotely accurately. No brief inspection can possibly hope to assess that correctly. How many draught/air leaks are there? This will hve a massive effect on heat loss.
And your chances of encountering a "good installer" are slim. Most are in it to harvest the grant money. If the grants stop, they will disappear just as fast as insulation installers. Seems government lean nothing. Ever.
Note that despite all the fluff and PR, NO ONE will stand behind the installation and guarantee the running costs. Theres a couple of recent entrants that give the illusion that they are. But they are not really.
Until that happens, take up will be an uphill struggle.
Even if the grant continues to grow to the point 100% of the installation is paid for, that no help if the piss poor job of installing it means it costs 3 times more to run.
For anyone considering it, i say sit it out. In Wales we are already at up to £45k (probably about £25k actual work, the rest is just free money) of work at the taxpayers expense on non gas properties if you are on benefits or income under £31k. As they get more desperate to meet targets, they will just throw more money about. Just wait and let the government pay. Do i agree with that? Absolutely not. But its the direction of travel, like it or not.
Evanivitch said:
Reads like there's some issues with workmanship and billing.
I find it hard to believe a heatpump is working at all if a modern building is getting down to single digits overnight, so clearly there's an issue there.
Would be interesting to see what the ventilation solution is for those homes, whether there's MVHR or PIV.
No doubt, but, sadly, very common. There simply are not enough competent installers. I find it hard to believe a heatpump is working at all if a modern building is getting down to single digits overnight, so clearly there's an issue there.
Would be interesting to see what the ventilation solution is for those homes, whether there's MVHR or PIV.
Snow and Rocks said:
I always find it amusing when people say that an ASHP will be perfectly economical if you have a really well insulated house - feels a bit like saying a Range Rover V8 is affordable to run if you buy a house next door to your office.
Yes an ASHP might be viable in a really well insulated house but what would it cost to heat that same insulated house with a gas boiler? I'd put money on it being cheaper overall and you wouldn't have to deal with the inflexibility of the heat pump.
You are not supposed to say that!Yes an ASHP might be viable in a really well insulated house but what would it cost to heat that same insulated house with a gas boiler? I'd put money on it being cheaper overall and you wouldn't have to deal with the inflexibility of the heat pump.
Using logic can get you into all sorts of bother.
Ill be sticking with my oil for the forseeable. Even if i fitted an ASHP, it simply makes no economic sense at all given the high cost of installation and insulation, even if running costs were halved. Well, unless i live to 100. Not likely with my track record!
Some facts about my ASHP for your consideration:
3,000 sq ft house built in 2022, EPC rating B
UFH downstairs, radiators upstairs
12kw Vaillant Arotherm + ASHP
300L pressurised cylinder
Downstairs generally set at 19.5 degrees. I find that UFH makes it feel warmer than equivalent temp in a radiator heating house. scale that back by couple of degrees overnight. Upstairs set at 17.5 degrees because we like it a little cooler for sleeping. In general the house feels warm and comfortable.
Direct debit is currently £220 per month but I think we'll have a small surplus come the end of the year.
Hot water set to 50 degrees and always on. Losses through the tank are minimal so makes sense just to keep it at a constant 50 degrees.
Hot water will run out after a bath or a few long showers. It takes 20-30 minutes to heat up again.
3,000 sq ft house built in 2022, EPC rating B
UFH downstairs, radiators upstairs
12kw Vaillant Arotherm + ASHP
300L pressurised cylinder
Downstairs generally set at 19.5 degrees. I find that UFH makes it feel warmer than equivalent temp in a radiator heating house. scale that back by couple of degrees overnight. Upstairs set at 17.5 degrees because we like it a little cooler for sleeping. In general the house feels warm and comfortable.
Direct debit is currently £220 per month but I think we'll have a small surplus come the end of the year.
Hot water set to 50 degrees and always on. Losses through the tank are minimal so makes sense just to keep it at a constant 50 degrees.
Hot water will run out after a bath or a few long showers. It takes 20-30 minutes to heat up again.
Olivera said:
From the news recently: https://news.stv.tv/north/tomintoul-government-fun...
Yes council mandarins have fitted air source heat pumps to houses in one of the coldest and most inhospitable places in the UK.
Yes council mandarins have fitted air source heat pumps to houses in one of the coldest and most inhospitable places in the UK.
That is a great real life example of what you can expect from them in the colder months, ie. nothing, without calling the grid and then giving you tepid water if you're lucky, in exchange for a £3000 leccy bill.They're are a total nonsense and absolutely nobody would have one nor even talk about them if not for the government "free" money paying for them.
Again : if there's a government grant for something, it's guarateed to be s
t.r3g said:
Olivera said:
From the news recently: https://news.stv.tv/north/tomintoul-government-fun...
Yes council mandarins have fitted air source heat pumps to houses in one of the coldest and most inhospitable places in the UK.
Yes council mandarins have fitted air source heat pumps to houses in one of the coldest and most inhospitable places in the UK.
That is a great real life example of what you can expect from them in the colder months, ie. nothing, without calling the grid and then giving you tepid water if you're lucky, in exchange for a £3000 leccy bill.They're are a total nonsense and absolutely nobody would have one nor even talk about them if not for the government "free" money paying for them.
Again : if there's a government grant for something, it's guarateed to be s
t.Can i add my install to the chat:
140m2 detatched house, some double - some triple glazing, cavity insulated and externally insulated too. Solar panels and battery with EV tariff.
ASHP: 8.5kw ecodan, with internal radiators swapped out to heating/cooling fan coil units.
Our monthly electric bill is £120/month in winter, free for the other 3 seasons.
The old gas boiler couldnt give us free hot water, nor could it cool, nor could it use night time cheap rate electric.
I installed it myself so the system was correctly installed (all new piping to correct sizes, new previously mentioned radiators).
Costs:
Heat pump £1500
Tank £400
Piping £2000
Radiators: £4000 - this is worthy of another thread, they came from italy and I was charged a lot of tax!
140m2 detatched house, some double - some triple glazing, cavity insulated and externally insulated too. Solar panels and battery with EV tariff.
ASHP: 8.5kw ecodan, with internal radiators swapped out to heating/cooling fan coil units.
Our monthly electric bill is £120/month in winter, free for the other 3 seasons.
The old gas boiler couldnt give us free hot water, nor could it cool, nor could it use night time cheap rate electric.
I installed it myself so the system was correctly installed (all new piping to correct sizes, new previously mentioned radiators).
Costs:
Heat pump £1500
Tank £400
Piping £2000
Radiators: £4000 - this is worthy of another thread, they came from italy and I was charged a lot of tax!
r3g said:
That is a great real life example of what you can expect from them in the colder months, ie. nothing, without calling the grid and then giving you tepid water if you're lucky, in exchange for a £3000 leccy bill.They're are a total nonsense and absolutely nobody would have one nor even talk about them if not for the government "free" money paying for them.
Again : if there's a government grant for something, it's guarateed to be s
t.Right tool for the right job. We did our research, and bought the right tool. Same reason I don't use a hammer to install screws.
Load of rubbish. That's why they need grants and eco waffle.
We are off mains gas and don't have any central heating so I really wanted them to work but whenever I've looked into it they just don't stack up. We use electric heaters and a woodburning stove for heating and an old gravity fed hot water tank with immersion heaters for hot water. The house is reasonably well insulated with small rooms, but if I brought it up to the standards recommended for ASHPs then I probably wouldn't need any heating at all. Electric radiators are way more expensive per kW of heat bur they're typically on for 30 mins at a time then off again using none.
If you're building a brand new house with very high spec insulation then they might be worth a look but retrofitting it to a typical house is a non-starter.
We are off mains gas and don't have any central heating so I really wanted them to work but whenever I've looked into it they just don't stack up. We use electric heaters and a woodburning stove for heating and an old gravity fed hot water tank with immersion heaters for hot water. The house is reasonably well insulated with small rooms, but if I brought it up to the standards recommended for ASHPs then I probably wouldn't need any heating at all. Electric radiators are way more expensive per kW of heat bur they're typically on for 30 mins at a time then off again using none.
If you're building a brand new house with very high spec insulation then they might be worth a look but retrofitting it to a typical house is a non-starter.
eniacs said:
Can i add my install to the chat:
140m2 detatched house, some double - some triple glazing, cavity insulated and externally insulated too. Solar panels and battery with EV tariff.
ASHP: 8.5kw ecodan, with internal radiators swapped out to heating/cooling fan coil units.
Our monthly electric bill is £120/month in winter, free for the other 3 seasons.
The old gas boiler couldnt give us free hot water, nor could it cool, nor could it use night time cheap rate electric.
I installed it myself so the system was correctly installed (all new piping to correct sizes, new previously mentioned radiators).
Costs:
Heat pump £1500
Tank £400
Piping £2000
Radiators: £4000 - this is worthy of another thread, they came from italy and I was charged a lot of tax!
Accepting that your radiators were expensive, much more than would normally be the case, one has to ask, how, with a £7.5k grant, the installers still want 10-15k off the customer.140m2 detatched house, some double - some triple glazing, cavity insulated and externally insulated too. Solar panels and battery with EV tariff.
ASHP: 8.5kw ecodan, with internal radiators swapped out to heating/cooling fan coil units.
Our monthly electric bill is £120/month in winter, free for the other 3 seasons.
The old gas boiler couldnt give us free hot water, nor could it cool, nor could it use night time cheap rate electric.
I installed it myself so the system was correctly installed (all new piping to correct sizes, new previously mentioned radiators).
Costs:
Heat pump £1500
Tank £400
Piping £2000
Radiators: £4000 - this is worthy of another thread, they came from italy and I was charged a lot of tax!
Oh, wait, that right, the £7.5k is just extra free money for the grant harvesters, sorry, i mean installers.
At £7.5K, the systems should be free for "normal" size houses or close to it.
Lots of people getting very wealthy off the back of the taxpayer.
monkfish1 said:
Accepting that your radiators were expensive, much more than would normally be the case, one has to ask, how, with a £7.5k grant, the installers still want 10-15k off the customer.
Oh, wait, that right, the £7.5k is just extra free money for the grant harvesters, sorry, i mean installers.
At £7.5K, the systems should be free for "normal" size houses or close to it.
Lots of people getting very wealthy off the back of the taxpayer.
Octopus have been doing heat pumps for a fee hundred quid with grant supplied.Oh, wait, that right, the £7.5k is just extra free money for the grant harvesters, sorry, i mean installers.
At £7.5K, the systems should be free for "normal" size houses or close to it.
Lots of people getting very wealthy off the back of the taxpayer.
Andeh1 said:
The problem with them is when utter numpties who do a straight swap with a gas boiler without researching them, then cry foul when their drafty uninsulated house stays cold.
True to a point, but a lot of these "numpties" are people like my parents in their late 70s, not that street wise who very nearly got bamboozled and pressured into just such an install in their totally unsuitable house by a pushy salesman with a load of glossy brochures (with smal print.)Old people who think they are being green and saving money, and it must be all good because the government are supporting it and even helping pay for it.
In fact the government are achieving the omni whammy of promoting sharp practice verging on corruption, discrediting a potentially good technology by pushing inappropriate use of it and wasting heaps of money in the process.
r3g said:
Olivera said:
From the news recently: https://news.stv.tv/north/tomintoul-government-fun...
Yes council mandarins have fitted air source heat pumps to houses in one of the coldest and most inhospitable places in the UK.
Yes council mandarins have fitted air source heat pumps to houses in one of the coldest and most inhospitable places in the UK.
That is a great real life example of what you can expect from them in the colder months, ie. nothing, without calling the grid and then giving you tepid water if you're lucky, in exchange for a £3000 leccy bill.They're are a total nonsense and absolutely nobody would have one nor even talk about them if not for the government "free" money paying for them.
Again : if there's a government grant for something, it's guarateed to be s
t.Right now you're just coming across as the same sort of thoughtless moron that buys an electric car without any sort of home charging capability yet needs to be able to tow a boat 300+ miles at drop of the hat in the dead of winter. So because they don't suit you, they therefore don't suit anyone.
monkfish1 said:
Lots of people getting very wealthy off the back of the taxpayer.
They're getting rich because like every other govt scheme it encourages rentseeking; don't subsidise the installation, subsidise the material. Every fking time it's the same st; solar panels, insulation, woodchip boilers.Evanivitch said:
monkfish1 said:
Accepting that your radiators were expensive, much more than would normally be the case, one has to ask, how, with a £7.5k grant, the installers still want 10-15k off the customer.
Oh, wait, that right, the £7.5k is just extra free money for the grant harvesters, sorry, i mean installers.
At £7.5K, the systems should be free for "normal" size houses or close to it.
Lots of people getting very wealthy off the back of the taxpayer.
Octopus have been doing heat pumps for a fee hundred quid with grant supplied.Oh, wait, that right, the £7.5k is just extra free money for the grant harvesters, sorry, i mean installers.
At £7.5K, the systems should be free for "normal" size houses or close to it.
Lots of people getting very wealthy off the back of the taxpayer.
JuanCarlosFandango said:
In fact the government are achieving the omni whammy of promoting sharp practice verging on corruption, discrediting a potentially good technology by pushing inappropriate use of it and wasting heaps of money in the process.
This ^^^^^Again. Just like last time with insulation.............
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