ASHP on a low income: a cautionary tale
This is a 'cautionary tale' for anyone thinking of getting an ASHP who is on a fixed low income and/or uses their current means of heating very sparingly. I was lucky enough to get a Green Homes Grant which covered most of the installation cost and had expected the running costs to be simlar (or possibly even a little less) than a gas combi boiler. What I hadn't grasped though was the very different way it mean of heating my house. Previously, because my income is very small, I ran the heating only when absolutely needed (and generally less than was really needed for health); with the ASHP, the advice is to leave it on 24/7 at a constant (or near-constant) temperature. Even before the worst of the utility prices leap, this saw my bills tripling last winter. This winter, my plan is to keep the temperature as low as I can in order to minimise the risk of the house becoming damp and then to wear multi-layer thermals, hot water bottles, spend more time in bed, etc. This would have been so even if prices hadn't surged, but even at the heating level I'm now looking at, I have no idea how I'm going to cope financially from this point on. I'm not advising anyone else not to get an ASHP, but if you heat your house in a similar way to me pre-heat pump, think very carefully about what the 24/7 might mean in practice.
Thanks for sharing your experiences @zoomuno.
Was this (running the ASHP 24/7) explained to you when you purchased the heat pump, and did you get a breakdown showing comparative running costs between gas and the ASHP? Is your house well insulated?
Buy Bodge Buster – Homeowner Air Source Heat Pump Installation Guide: https://amzn.to/3NVndlU
From Zero to Heat Pump Hero: https://amzn.to/4bWkPFb
Subscribe and follow our Homeowners’ Q&A heat pump podcast
Thanks, Mars. The 24/7 things was explained to me when I purchased. I would say the breakdown made many assumptions about how the house would usually be heated (without making them explicit). I've refined my usage after reading a lot of posts here (thank you!) and taking advice from Midea. House is very well insulated. I'm not sure I can do much else (though open to suggestions).
Whilst I read up on heat pumps (pros and cons), I ultimately didn't grasp what it would mean in the day to day usage, and perhaps I couldn't have done fully without this practical experience. I do regret going ahead (and regret reaching that conclusion because I very much want to move towards more sustainable living). I'll see how this winter goes, but I might end up borrowing money to install a gas boiler again (and can hardly believe I'm having to consider this!). Obviously the dramatic increase in fuel tariffs has made things much worse (for everyone) and I wouldn't say to someone else in my position that they shouldn't go ahead. However, I'd advise them to be wary that there seems to be no information out there on the implications for people who are on low incomes (benefits/minimum wage/precarity, and with no possibility of improving their financial circumstances).
Posted by: @zoomunoThanks, Mars. The 24/7 things was explained to me when I purchased. I would say the breakdown made many assumptions about how the house would usually be heated (without making them explicit). I've refined my usage after reading a lot of posts here (thank you!) and taking advice from Midea. House is very well insulated. I'm not sure I can do much else (though open to suggestions).
Whilst I read up on heat pumps (pros and cons), I ultimately didn't grasp what it would mean in the day to day usage, and perhaps I couldn't have done fully without this practical experience. I do regret going ahead (and regret reaching that conclusion because I very much want to move towards more sustainable living). I'll see how this winter goes, but I might end up borrowing money to install a gas boiler again (and can hardly believe I'm having to consider this!). Obviously the dramatic increase in fuel tariffs has made things much worse (for everyone) and I wouldn't say to someone else in my position that they shouldn't go ahead. However, I'd advise them to be wary that there seems to be no information out there on the implications for people who are on low incomes (benefits/minimum wage/precarity, and with no possibility of improving their financial circumstances).
As long as you have correctly sized radiators it's a bit of a myth that you have to run an ASHP 24/7. (if you have underfloor heating it's different).
An ASHP does lose efficiency when you heat the water/let it cool repeatedly but it's not that much. My ASHP is off 12-5am and that is definitely cheaper than running it all night. My house heats up quite quickly in the morning. Having your heating varying by about 5 degrees, say between 15 and 20C is fine for an ASHP. If your heating cost tripled there might be something else going on.
Do you know how your ASHP is set up; for example, how is the radiator flow temperature controlled and what temperature is your hot water (and how much do you use)?
Thanks @kev-m. So would you switch off at night at any time of the year? In winter, my house would cool a lot if I switched off overnight, so I'm guessing the ASHP would have to work very hard during the day and might take most of the day to get to a reasonable temperature (and might take several hours if I lowered it as much as 5 degrees at night). Last winter, I most aimed for a daytime temperature of 16 or 17 degrees because of cost (not good with chronic health condition :-/ ) and 14-15 at night (but pump kept coming on during night and I found the temp too high).
The rads have been confirmed as correct size. Do you know how I can check rad flow temp control? Hot water temp is at 45 degrees. I use very little: wash up once or twice a week; shower less than average (chronic health again as opposed to bad hygiene!), but also keep hot water use to minimum (rinse hair on cold). Ridiculous really to be in this position! It would be lovely to find a way to keep the house warmer, but it's reducing the overall bill that's the priority in hopes I can avoid going back to gas.
@zoomuno Have you had your radiators balanced, this can contribute to the high usage if incorrectly balanced. Balancing reduced my consumption significantly.
@zoomuno
Yes to switching off all year. My house drops from 20C or so to 15 overnight in the winter. My house is quite well insulated but only to 1990 standard with a bit extra loft insulation.
What make, model and kW rating ASHP do you have? If you tell us someone will probably be familiar with it. Also, what size and age is your house? Do you know if your ASHP is working on weather compensation? If it is then the rads will be hotter when it's colder outside. That's normally the most efficient way to run an ASHP. Are your radiators ever hot as in too hot to comfortably keep your hand on?
45C is about right for water for most people; ours is 47. Rinsing hair in cold is only going to save pennies; it's heating and/or lots of long baths and showers that rack up the pounds.
I do feel for you and hope you can at least be comfortable. If it's any consolation (and it probably isn't) at today's prices I doubt gas CH would be much cheaper to run.
Thank you @prjohn I'm pretty sure they were balanced at the time of installing, but I'll definitely look into this.
@kev-m Wow, that's interesting (the switching off). I'll experiment with that come autumn.
The pump is a Midea monobloc model MHC-V10W/D2N8-B. Heating capacity says 10kW. House is three-bed semi (cavity wall insulated and well insulted loft), built 1948 but with 2022 timber built single-storey extension (insulated to max). Yes, pump is working on weather compensation. Radiators are never hot, at most luke warm in winter.
Thanks so much for your response. I'm wowed by the knowledge and generosity on this forum!
@zoomuno
It sounds as if you have the basics right. Have a look at these threads that discuss Midea ASHPs.
There are some links/references that may be useful.
What does your EPC say for the energy and hot water consumption for your house? It can be useful to give a rough estimate of how many kWh your ASHP is likely to consume in a year.
I would be tempted if only for interest to work out how much your old mains gas boiler would have cost to run given the dramatic increases in gas prices, even higher in percentage terms than the increases in electricity prices.
Do you know what your annual consumption was for gas in kWh when you use to have a gas boiler?
Hi @jeff So my dual fuel costs for 12 months to October 2021 was £373. (My bills were extremely low compared to most households, but that kept it affordable.) My utility company (electricity only now) now wants to put my DD up to £165/month (I've resisted, but there's a debt building so I'm going to have to bite the bullet). That difference, if my maths is right and taking into account a price hike of 54%, has a little more than trebled the original costs, but I have a few additional costs since then that account for that extra.
- 22 Forums
- 2,047 Topics
- 44.7 K Posts
- 10 Online
- 3,274 Members
Join Us!
Trusted Installers
Struggling to find a reliable heat pump installer? A poor installation can lead to inefficiencies and high running costs. We now connect homeowners with top-rated installers who deliver quality work and excellent service.
✅ Verified, trusted & experienced installers
✅ Nationwide coverage expanding
✅ Special offers available
Latest Posts
-
RE: Yes, the "zoning with ASHP" topic again...
James, On your question: Please explain why a highe...
By HarryRea , 3 hours ago
-
RE: Commencing on an ASHP Installation Process
I think you may very well be right and of course A2A ca...
By JamesPa , 5 hours ago
-
-
RE: Renewables & Heat Pumps in the News
Yes, it's far too much money. DESNZ will no doubt wis...
By Transparent , 11 hours ago
-
That all sounds very believable. Presumably mixing of ...
By JamesPa , 14 hours ago
-
RE: Battery sizing - How low can you go!
@bontwoody Hope this is legible
By ChandyKris , 19 hours ago
-
RE: Agile: average import cost vs other tariffs?
@old_scientist We are with SSEN and our G99 application...
By Toodles , 1 day ago
-
RE: Solar Power Output – Let’s Compare Generation Figures
Yes. Storing the solar generation within the home is gr...
By Transparent , 2 days ago
-
RE: ASHP Ecodan L9 error - No Heating but Hot Water
@phoenix15, @heacol cover your area… I’d strongly recom...
By Mars , 2 days ago
-
RE: Warm weather and heat pumps.
@editor Oh nothing right now because $ needed for struc...
By Lucia , 2 days ago
-
RE: Potentially more choice including air to air heat pump grants
@jeff Such documents are far too wordy for my ‘daily re...
By Toodles , 2 days ago
-
RE: Getting the best out of a heat pump - is Homely a possible answer?
@grahaml I cannot agree that it is a small percentage o...
By benson , 3 days ago
-
RE: Samsung Gen6 16kW tribulations
@emceed, can you please give us an update on your syste...
By Mars , 4 days ago
-
What's the problem you are trying to solve. The answer...
By JamesPa , 6 days ago
-
Good luck. For what it is worth my system was very def...
By JamesPa , 7 days ago
-
RE: Massive Electricity Cost for Running My Air Source Heat Pump
I agree @mark-h The Building Regs are now very readable...
By Transparent , 1 week ago
-
RE: Help me understand my Mitsubishi Ecodan system
@carpenterstation When changing settings in the ser...
By RobS , 1 week ago
-
RE: Ecodan Legionella cycle - immersion heater problem
Thanks for letting us know @clockworks I admire your ...
By Transparent , 1 week ago
-
RE: Revised version of MCS-020 (noise standards for heat pumps)
As you say this is no change, which I personally think ...
By JamesPa , 1 week ago