To be honest, I'm going a little cold (Sorry) on the idea of an ASHP.
The companies I have found only have a few case studies on their websites and it seems next to impossible to talk to real people who have had an ASHP retrofit install and are happy with it. Is there anyone in Kent/East Sussex out there?
The next hurdle would appear to be the heat loss survey. Although there seems to be a standard, it seems that, in order to obtain three quotes, you need to pay three times?
Finally what companies based in Kent/East Sussex would people recommend who have actually had them install their ASHP?
I'll hold my hands up to being a little cynical but I suspect the good companies are too busy to need to look for work?
Although we live in Surrey, the company we ended up settling on (Doré Woodman, as mentioned in multiple of my other posts) certainly also covers Kent and Sussex, so would seem appropriate. Ours was certainly a retrofit installation - a 1930s property with an extension from around the millenium - and we have definitely been very happy with the level of workmanship, knowledge and support provided. When we recommended them to our neighbours (similar basic property but modernised in a different way), Doré Woodman made a list of recommendations of improvements they felt the neighbours should spend their money on before contemplating an ASHP install, so I'm also confident in saying the installer will talk you out of an ASHP unless it's an appropriate piece of work to be undertaken.
If you decide to have a chat with them (you'll probably talk to Alison in the first instance), I'm quite happy for them to use our place as a reference site. However, I suspect they may well have others nearer to you which might be better and easier. The option is open, though.
105 m2 bungalow in South East England
Mitsubishi Ecodan 8.5 kW air source heat pump
18 x 360W solar panels
1 x 6 kW GroWatt battery and inverter
Raised beds for home-grown veg and chickens for eggs
I know that Evergreen and Homely are one and the same, what I wanted to be sure about is whether @jswhite's Evergreen are one and the same. I think we can take it from his reply they are. In my view, this has implications for Homely - if a company is suspect in one area of operations, it has to raise questions (which I haven't answered) about other areas of operation. Again I have to acknowledge we are talking about allegations here, all are free to take heed or ignore them as they wish.
They offer "free" two minute online quotes in exchange for your postcode and email address. Quite how they manage to provide a quote (not an estimate) on very scanty details collected online is quite beyond me. Maybe it is so they can put you on their nibblers list and start putting the pressure on.
Although we live in Surrey, the company we ended up settling on (Doré Woodman, as mentioned in multiple of my other posts) certainly also covers Kent and Sussex, so would seem appropriate. Ours was certainly a retrofit installation - a 1930s property with an extension from around the millenium - and we have definitely been very happy with the level of workmanship, knowledge and support provided. When we recommended them to our neighbours (similar basic property but modernised in a different way), Doré Woodman made a list of recommendations of improvements they felt the neighbours should spend their money on before contemplating an ASHP install, so I'm also confident in saying the installer will talk you out of an ASHP unless it's an appropriate piece of work to be undertaken.
If you decide to have a chat with them (you'll probably talk to Alison in the first instance), I'm quite happy for them to use our place as a reference site. However, I suspect they may well have others nearer to you which might be better and easier. The option is open, though.
Thank you. That's the feedback I'm after. As you say, they may be out of area but they sound genuine.
"Quite how they manage to provide a quote (not an estimate) on very scanty details collected online is quite beyond me. Maybe it is so they can put you on their nibblers list and start putting the pressure on. "
This is the thing, I'm might look somewhat stupid after this reply, but I did receive a 'quote' of £9.5K and an assurance that I qualified for a £10k grant. Moving on to next stage, on the hook and wriggling. Heat Loss calcs and the 'quote' was suddenly £17,700 which elicited a sex and travel response.
Even more stupidly, when they reduced to £12.2k I agreed. Dumb. Looking back I can't believe I fell for it. The only difference between the highest quote and the accepted one was five radiators. Not £5ks worth..
It was a rush as the grant deadline was only days away. Not my finest hour. It was only after Heat Pump was turned on and the smart meter started laughing that I realised I'd been more stupid than the numbers suggest.
We used a local M&E contractor who got a system design from Mitsubishi (foc) we had exhausted the renewables companies that had been established for more than 3 years as the new starts were almost all phoenix companies.
One thing we did find was the cost difference the M&E guys were happy to share the cost price of the kit which incidentally was 50%+ less than the renewable companies. It did appear that the renewables companies quotes were cost plus fitting plus the grant you were due to get back! Our most expensive for the same kit but less plumbing work was 42k more than we have paid! The others were still 28-30k more than we have paid! As a benchmark the 2 x 14kw ASHP were less than 9k
To be honest, I'm going a little cold (Sorry) on the idea of an ASHP.
The next hurdle would appear to be the heat loss survey. Although there seems to be a standard, it seems that, in order to obtain three quotes, you need to pay three times?
I'll hold my hands up to being a little cynical but I suspect the good companies are too busy to need to look for work?
If you're on this forum, would really recommend you do the heat loss calculations yourself. you don't need to be engineer, just able to measure and have knowledge how your house is built. The spreadsheets have been published by others in this forum. There's also an online one at heatpunk.co.uk (just register as john smith heating company, its not checked).
You can then get the retail cost of an appropriate size heatpump from a number of online suppliers (such as midsummer wholesale and others). radiators are also easy to cost - use stelrad to get the outputs at heat pump temperatures to get sizing (the heat loss tools will do this for you as well), then screwfix for radiator costs. you can then do the maths on what they are quoting you - subtract the obvious large item materials, then see whats left for Time and Sundries. It can be bonkers. I have had several a couple years back inflating the quote by the amount that you'd hopefully get back in grant (In RHI days .. more than £10000) they all got told to take a walk. so I haven't done it yet....
The other thing you can do which is surprisingly useful, is find a way to measure the heat usage of your current system on a cold day. As a really basic measure, photograph or write down your gas (or oil?) meter reading at the same time each day. Better, do it hourly. Then do the maths.
Even better, if you have a smart gas meter , download the "hildebrand bright" app, register your meter details, and you'll be able to see 30 minute meter readings on your phone, for free. Therefore you know how much kwh of gas you burn per hour. multiply by the efficiency of your boiler (which can be a difficult one to get right, but probably lower than you think) and you know the heat input going into your house.
I'm doing all of these as a prelude to getting a heat pump - I haven't got one yet. so far the "actual usage" data is telling me that my house is slightly better (10-12kw) than what the MCS calculations suggest (14-16kw). But I'll probably go larger on the HP anyway for safety margin!
One thing that I would definitely recommend, whether you eventually go for a heat pump or not, is to try to improve the energy efficiency of your home.
I'm doing all of these as a prelude to getting a heat pump - I haven't got one yet. so far the "actual usage" data is telling me that my house is slightly better (10-12kw) than what the MCS calculations suggest (14-16kw). But I'll probably go larger on the HP anyway for safety margin!
Empirical heat loss assessments, done of a cold design temp day, tend to get sniffed at these days, but in fact I think it may be one of the most accurate ways of getting a real figure rather than a 'modelled' method.
The key to getting the right size heat pump is tear up all the brochures sales pitches downright lies and other bull$hit and instead get the manufacturer's engineering data tables for outputs. These still aren't perfect, but they are much better, and much more detailed. You need to match, and then add a bit, your heat loss at your design LWT at around zero to minus two ambient. For example, my 14kW rated Midea heat pump only delivers just over 11kw in these conditions, which is just when you need the heating the most. Midea may we worse than some others, but they all do this. My heat loss (calculated) at design conditions is around 12.3kW so you can see what is going to happen, and it does happen, the house runs cold in cold weather.
Midea 14kW (for now...) ASHP heating both building and DHW
Empirical heat loss assessments, done of a cold design temp day, tend to get sniffed at these days, but in fact I think it may be one of the most accurate ways of getting a real figure rather than a 'modelled' method.
The key to getting the right size heat pump is tear up all the brochures sales pitches downright lies and other bull$hit and instead get the manufacturer's engineering data tables for outputs. These still aren't perfect, but they are much better, and much more detailed. You need to match, and then add a bit, your heat loss at your design LWT at around zero to minus two ambient. For example, my 14kW rated Midea heat pump only delivers just over 11kw in these conditions, which is just when you need the heating the most. Midea may we worse than some others, but they all do this. My heat loss (calculated) at design conditions is around 12.3kW so you can see what is going to happen, and it does happen, the house runs cold in cold weather.
I'd have thought from a scientific point of view, the experimental evidence should always be more valid than the theoretical numbers. we had a really good design conditions day on the 11th december - it never got over minus 1, and as we had house guests, all bedrooms and reception rooms were in use and heated to a minimum of 19C, some 20 or 21.
the smart gas meter gave me this
and there are no other heat sources, and gas is not used for anything else. so based on this (minus say 15% for loss from a modern mod-con boiler) I think I have a pretty good idea where I need to be on heat pump sizing. The fact that its lower than my MCS theoretical method number - tells me that I am "definitely warm enough" if I get a pump specced to the theoretical method number, and can drop it down a bit if I need to to make the engineering work . (with various mitigations options for worst case days including but not limited to : work on improving heat-loss of house , backup heaters , heat less rooms, etc...).
but yes I totally agree, you have to study the output tables for your proposed heat pump to see how it does at the low outside temps when you'll actually need it . It has surprised me how bad the heat pump vendors are at assign highly optimistic model numbers based on nominal capacities in "best case situation test conditions" and these capacities don't hold true in the conditions that actually matter - i.e. when its proper cold out!
@derek-m I've been trying to think of a solution to this. Apparently the inner wall and outer stone is not suitable for cavity insulation. I was wondering if I could line the inner wall (and ceiling) with kingspan or equivalent straight onto the current plaster and then finish off with something a little more attractive. Half the room is already well insulated but the other half might benefit. We would lose width on a 3.3metre wide room but could probably live with that if it made a difference.
Empirical heat loss assessments, done of a cold design temp day, tend to get sniffed at these days, but in fact I think it may be one of the most accurate ways of getting a real figure rather than a 'modelled' method.
The key to getting the right size heat pump is tear up all the brochures sales pitches downright lies and other bull$hit and instead get the manufacturer's engineering data tables for outputs. These still aren't perfect, but they are much better, and much more detailed. You need to match, and then add a bit, your heat loss at your design LWT at around zero to minus two ambient. For example, my 14kW rated Midea heat pump only delivers just over 11kw in these conditions, which is just when you need the heating the most. Midea may we worse than some others, but they all do this. My heat loss (calculated) at design conditions is around 12.3kW so you can see what is going to happen, and it does happen, the house runs cold in cold weather.
I'd have thought from a scientific point of view, the experimental evidence should always be more valid than the theoretical numbers. we had a really good design conditions day on the 11th december - it never got over minus 1, and as we had house guests, all bedrooms and reception rooms were in use and heated to a minimum of 19C, some 20 or 21.
the smart gas meter gave me this
and there are no other heat sources, and gas is not used for anything else. so based on this (minus say 15% for loss from a modern mod-con boiler) I think I have a pretty good idea where I need to be on heat pump sizing. The fact that its lower than my MCS theoretical method number - tells me that I am "definitely warm enough" if I get a pump specced to the theoretical method number, and can drop it down a bit if I need to to make the engineering work . (with various mitigations options for worst case days including but not limited to : work on improving heat-loss of house , backup heaters , heat less rooms, etc...).
but yes I totally agree, you have to study the output tables for your proposed heat pump to see how it does at the low outside temps when you'll actually need it . It has surprised me how bad the heat pump vendors are at assign highly optimistic model numbers based on nominal capacities in "best case situation test conditions" and these capacities don't hold true in the conditions that actually matter - i.e. when its proper cold out!
it's worse than that because although some manufacturers make an allowance for defrosts, in my experience it's nowhere near enough. In a defrost cycle, which in cold, damp weather can be every hour, the ASHP stops heating for about 10 minutes. So that's 15-20% down. But it's worse than that because when it starts again it's lost several degrees of flow temp and has to build that up again.
