ASHP for a flat - (A2A; grants)

[magnayn]

We own a small flat (46 m^2) (detatched, above our garage) that we rent out.

 

The heating/DHW comes from a boiler that is shared with our house, on a separate heating zone. DHW really means 'kitchen/bathroom tap', as the shower is an electric unit. About 60% of the floor area is open-plan (but with an open ceiling to the pitched roof) and a bedroom & study for the rest.

 

Back when gas was 3p/kWh, we used to rent it on a "heating included in the rent" basis. However, rising costs and seeing the boiler on full blast on a warm day with all the windows open means this is feeling like an untenable situation, not least for my own sanity.

 

My go-to solution was to simply install a second boiler, buy a 2nd hand domestic gas meter and apportion costs that way. But this does mean at least a degree of faff in citing a new flue and getting a gasman to commission.

 

I was given pause when someone suggested I look an A2A heat pump as an alternative. Doing some initial investigations shows this does indeed look promising - and gives aircon as a bonus, but also that an unbelievable level of nonsense seems to be written about A2A by organisations that really ought to know better, determined for reasons I cannot understand to install more complicated A2W systems. 

 

These units are very attractively priced - certainly comparable to the gas alternative. I could simply replace the heating and leave the hot water well alone, as the amount used will be absolutely microscopic - fitting complicated tanks would never show an ROI in a million lifetimes.

 

Or, I could pursue some form of grant-based scheme to cover the cost (the property is registered separately with its' own EPC). I can't find a canonical description of what the rules are for 'boiler upgrade scheme' - I understand A2A used to be excluded in prior RHI schemes (which I guess explains the FUD), and I've seen mention that there were rules about it covering hot water too? I'm not against doing that per-se (if someone's going to pay me to do a silly thing), but I am against spending money without sense.

 

A2A Good/bad idea? Recommendations / things to consider if so or alternatives if not..

[JohnMo]

Nothing wrong with A2A, can be very cheap to run. But has to installed by certified person for F gas. No grants, but should be vat free.

 

Is it an Airbnb type of rental or long term? 

 

A cheaper more sensible option would be to spend a little to make your heating controls not playable with and more automated, with simple sensors that says window open heating off. Have time control wireless, away from end user in your hands.

[DougMLancs]

My brother has his detached 4 bed bungalow on just two A2A units and is very happy with it. Install costs were low and way more efficient than his old storage heaters. I would second retaining some control over any heating system and bear in mind if you go A2A then you’ll also have to manage/disable cooling. 

[magnayn]

1 hour ago, JohnMo said:

Nothing wrong with A2A, can be very cheap to run. But has to installed by certified person for F gas. No grants, but should be vat free.

 

Yeah - I'm aware of the F-Gas restriction. Fortunately I know someone who has just recently been certified, and that it's not actually hideously expensive to do so, so I have options there. I've also seen there are non-HFC units now that don't need F-Gas; they seem to claim SCOP of 4.2 - I presume they're less good than the other units.

 

I'm a little unsure on sizing and number of emitters though - any good resources around?

 

1 hour ago, JohnMo said:

Is it an Airbnb type of rental or long term? 

 

Long-term. It's actually got a multi-time by desired temperature controller, and frankly nobody that's lived there has ever seemed to be able to be bothered to operate it correctly. I briefly considered upgrading it to something like nest, but I think the simple fact of the matter is if there's no financial consequence of your choices, then it's very hard to make anyone be bothered about it (and back when it was relatively cheap it didn't much matter). I could simply take the thermostat controls away, but I also don't want people to be cold and able to decide for themselves.

 

1 hour ago, DougMLancs said:

My brother has his detached 4 bed bungalow on just two A2A units and is very happy with it. Install costs were low and way more efficient than his old storage heaters. I would second retaining some control over any heating system and bear in mind if you go A2A then you’ll also have to manage/disable cooling. 

 

Yeah - I'd heard of that aspirational requirement. I guess they can dream!

 

 

 

 

 

 

 

[RobLe]

41 minutes ago, magnayn said:

I've also seen there are non-HFC units now that don't need F-Gas; they seem to claim SCOP of 4.2 - I presume they're less good than the other units.

There’s very little performance difference between refrigerants with fluorine (F gasses) and natural ones without (R290 - propane, R600 - butane).  R290 is in fact usually touted as more efficient and capable of higher temperatures.  F gasses worsen global warming, but are in general less flammable so preferred by a/c installers.  I think most manufacturers are moving towards the natural refrigerants, as F gasses are phased out one by one due to GBW issue.  There are minimum room sizes allowed for a given charge of R290, so that if it leaked out, it would not form an explosive mixture.

[magnayn]

29 minutes ago, RobLe said:

There’s very little performance difference between refrigerants with fluorine (F gasses) and natural ones without (R290 - propane, R600 - butane).  R290 is in fact usually touted as more efficient and capable of higher temperatures.

OOh - that's extremely interesting - thanks for this.

 

I guess inevitably the removal of the F-Gas requirement means these units will face some push-back simply because it means anyone can buy them, regardless of their merits. Frankly my initial efforts to educate myself about the ASHP market has led me to believe the government schemes are causing active damage to uptake as (e.g) A2A units are dismissed not because they're not good, but because they don't funnel buyers to £5,000 cash to spend on expensive installation.

[JamesPa]

11 hours ago, magnayn said:

Frankly my initial efforts to educate myself about the ASHP market has led me to believe the government schemes are causing active damage to uptake as (e.g) A2A units are dismissed not because they're not good, but because they don't funnel buyers to £5,000 cash to spend on expensive installation.

+1 on that conclusion.  With a few notable exceptions the Ill designed government schemes appear to be funding the grant harvesting industry, inhibiting new entrants or innovation, and not developing a path to mass adoption at a price people will be willing to pay.  

[RichardL]

Double edge sword -  keeping the grant harvesters away from the A2A installers is probably a good thing?

If the grant is a net 0 anyway (gov't subsidises, installer takes it - customer same price) - then the only harm may be the marketing of A2A?
The install itself remains with competent firms? 

[JamesPa]

31 minutes ago, RichardL said:

The install itself remains with competent firms? 

No comment!

[magnayn]

On 06/06/2023 at 13:00, RichardL said:

Double edge sword -  keeping the grant harvesters away from the A2A installers is probably a good thing?

If the grant is a net 0 anyway (gov't subsidises, installer takes it - customer same price) - then the only harm may be the marketing of A2A?
The install itself remains with competent firms? 

 

The government's stated objective is to decrease the usage of gas, by getting the public to switch over to electric heat pumps. 

 

"Harming the marketing of A2A" is, by extension, harming the uptake of ASHP, thus running contrary to the objective.

 

I think there's a large number of small dwellings for which A2A is much more appropriate (and, frankly, I'd dispense with the whole hot-water tank complexity and space consumption and use direct-heat instead - but another governmental obsession is "all or nothing" when they ought to be pursuing "any improvement we can get").

 

Telling untruths about A2A pushes people into A2W, they run the numbers and conclude the finances don't stack up. I can't see any change to that situation so long as the unit price differential between gas and electricity remains where it is. I cannot fathom why the government doesn't just make gas relatively more expensive, you wouldn't need grant schemes and the whole problem would solve itself.

[JamesPa]

3 hours ago, magnayn said:

 

The government's stated objective is to decrease the usage of gas, by getting the public to switch over to electric heat pumps. 

 

"Harming the marketing of A2A" is, by extension, harming the uptake of ASHP, thus running contrary to the objective.

 

I think there's a large number of small dwellings for which A2A is much more appropriate (and, frankly, I'd dispense with the whole hot-water tank complexity and space consumption and use direct-heat instead - but another governmental obsession is "all or nothing" when they ought to be pursuing "any improvement we can get").

 

Telling untruths about A2A pushes people into A2W, they run the numbers and conclude the finances don't stack up. I can't see any change to that situation so long as the unit price differential between gas and electricity remains where it is. I cannot fathom why the government doesn't just make gas relatively more expensive, you wouldn't need grant schemes and the whole problem would solve itself.

I agree with a lot of what you say and particularly the issue with a bias against A2A.  Having said that self-install single a2a units are available for not a lot of money and to be honest if 1 or 2 is all you need, then its still going to be comparable with a gas boiler without the grant.  This being the case I can see an argument for not subsidising them.  

 

Making gas more expensive is political suicide of course, which is why the Government wont do it.  If it were smart, what it would do is not allow gas prices to drop from their current elevated level as much as they otherwise would do.  A judiciously timed shift of the green taxes, which currently fall on electricity, to gas, would not be noticed in the general falling market price.  But that requires rapid, intelligent action with a laser focus on the (purported) end objective.  I'm not holding my breath!.

 

Much of the current problem, in my humble opinion (based on lots of reading and 2 years of trying to get a sensible proposal out of 'the industry') is down to the grant harvesting industry and their partners in crime, MCS.  The (almost) rigid rules imposed by the (almost) unavoidable requirement to have MCS certification (even if you don't want the grant) inhibit the innovation in installation practice which is needed to slash the total install costs and associated disruption.  From the point of view of the grant harvesters this is OK - so long as they follow the 'painting by numbers' recipe they are protected from any claim even though the result may be total cr*p.  Since many of them doubtless plan to go bust as soon as the grants dry up (as happened in the early days of solar), their reputation doesn't matter to them so long as they are protected from claims. 

 

A very small number of installers/specifiers seem to be emerging who are finding innovative ways to comply with MCS but at the same time deliver a cost effective and technically sane solution, however they are currently few and (literally far) between.  Octopus are also challenging the model, but focussing  it seems solely on a particular class of property. 

 

Edited June 7, 2023 by JamesPa

[magnayn]

15 hours ago, JamesPa said:

I agree with a lot of what you say and particularly the issue with a bias against A2A.  Having said that self-install single a2a units are available for not a lot of money and to be honest if 1 or 2 is all you need, then its still going to be comparable with a gas boiler without the grant.  This being the case I can see an argument for not subsidising them.  

 

Making gas more expensive is political suicide of course, which is why the Government wont do it.  If it were smart, what it would do is not allow gas prices to drop from their current elevated level as much as they otherwise would do.  A judiciously timed shift of the green taxes, which currently fall on electricity, to gas, would not be noticed in the general falling market price.  But that requires rapid, intelligent action with a laser focus on the (purported) end objective.  I'm not holding my breath!.

 

Oh, I agree completely - I wasn't trying to make a case that small-installation A2A ought to be subsidised; I think in general subsidies of this kind is a bad way to achieve the desired outcomes, though it's mired in the politics of gas prices (one reason that 2050 targets won't be met is the public won't wear it and politicians are delusional).  

 

Can you tell me more about MCS woes? I had to have that for Solar PV, but then the meter is paying me vastly subsidised FIT rates it didn't seem an unreasonable policy to mitigate against fraud. I'm expecting that one day it will be economically sensible for me to switch our house to a HP (I'm currently thinking 2; A2W for the new part that has UFH, possibly with A2A for the upstairs). I have zero intention of using contractors - I have a very, very low level of trust in their competence and they can't compete with my labour rates - but I will need to deep dive on design resources. Any pointers there too would be useful!

 

 

[JamesPa]

3 hours ago, magnayn said:

 

Oh, I agree completely - I wasn't trying to make a case that small-installation A2A ought to be subsidised; I think in general subsidies of this kind is a bad way to achieve the desired outcomes, though it's mired in the politics of gas prices (one reason that 2050 targets won't be met is the public won't wear it and politicians are delusional).  

 

Can you tell me more about MCS woes? I had to have that for Solar PV, but then the meter is paying me vastly subsidised FIT rates it didn't seem an unreasonable policy to mitigate against fraud. I'm expecting that one day it will be economically sensible for me to switch our house to a HP (I'm currently thinking 2; A2W for the new part that has UFH, possibly with A2A for the upstairs). I have zero intention of using contractors - I have a very, very low level of trust in their competence and they can't compete with my labour rates - but I will need to deep dive on design resources. Any pointers there too would be useful!

 

 

My thoughts  (like those of others on here) in relation to heat pumps are pretty well documented in other threads on this forum and I don't think I should labour them.  My biggest issues personally are

 

1. The fact that they have worked their way into permitted development rights so that the use of an MCS contractor (design + install, they cannot be split by the customer) is required if you are to install a heat pump without getting express planning consent, thus effectively creating a near-monopoly

 

2. The fact that they more or less insist on a method of calculating the system size which, for retrofits, ie their main market, may bear little or no relationship to reality.  This wouldn't matter except that system sizing is so crucial to the performance of the system, the cost and the disruption. 

 

3. The fact that their rules are largely about process not outcomes, which protects the installer not the consumer whilst at the same time stifling innovation

 

In fairness to MCS they have recognised (3) in their latest consultation, whether it will change I don't know. 

I recently challenged them on (2) and today received a response.   I intend to ask for permission to publish it as it deserves to be heard.  

I haven't yet engaged with them in respect of point (1).

 

I should add that I'm just a consumer, not from the trade, albeit a consumer with a background in engineering, a degree in physics and who has spent 2 years failing to get a quote from an MCS installer for a heat pump suitable for my property (I've had plenty of quotes!) and reading the experiences of other on this forum and elsewhere.

 

I suppose one could deploy the 'its early days and work in progress defence', to use software analogy - its still in beta testing.  However beta test software is generally declared as such and those who participate do so knowingly and are given meaningful feedback opportunities.    

 

In relation to solar PV, my comment was that lots of the early installers went bust when the grants dried up and I am guessing the same will happen with Heat Pumps.  Realistically people see an opportunity to harvest some taxpayer cash.  Some of those are competent, professional and value their reputations, because they intend to stay in business (feel free to complete the sentence).

 

As to design resources, I cant point at a 'handbook' (others may) but reading on this forum and watching heat geek and john cantor videos will help.  If you are designing for an existing property, get a smart meter for your gas (and the ability to download the readings)  asap, or take daily fuel consumption readings in the heating season if not on gas.  Note any changes you make to the way you use your heating.  This will give you an experimental determination of actual load.  Then use this information to sense test any system sizing done by spreadsheet.  Getting this right is more than half the battle.

[Crofter]

On 04/06/2023 at 15:02, DougMLancs said:

My brother has his detached 4 bed bungalow on just two A2A units and is very happy with it. Install costs were low and way more efficient than his old storage heaters. I would second retaining some control over any heating system and bear in mind if you go A2A then you’ll also have to manage/disable cooling. 

Hi, I'd be interested to hear more about this. Try as I might I can't find basic costs for A2A units online anywhere.

[DougMLancs]

9 hours ago, Crofter said:

Hi, I'd be interested to hear more about this. Try as I might I can't find basic costs for A2A units online anywhere.

Here’s his quote- fitted Sept last year in the Midlands

[Crofter]

1 hour ago, DougMLancs said:

Here’s his quote- fitted Sept last year in the Midlands

Thanks. How does the zero VAT rating work?

[DougMLancs]

Heat pumps are one of the energy-saving measures that are zero-rated for VAT. Installers shouldn’t be charging VAT on materials or installation. More info here https://www.gov.uk/tax-on-shopping/energy-saving-products

 

I think it has to be professionally installed to qualify for the zero rating though. If you went the DIY route then VAT would apply. Others will correct me if I’m wrong.

Edited June 9, 2023 by DougMLancs

[JohnMo]

The install and supply needs to be the same company on the same invoice to be zero vat.

[magnayn]

On 09/06/2023 at 01:15, Crofter said:

Hi, I'd be interested to hear more about this. Try as I might I can't find basic costs for A2A units online anywhere.

Sometimes helps to narrow the search to "air conditioning" as in the UK the conspiracy is to believe A2A is just for cooling.

 

E.g: https://www.saturnsales.co.uk/Stylish-Wall-Mounted.html gives you an idea of how much you're being rushed for installation (sundries like pipework notwithstanding).

 

In my own case I cannot see the VAT saving would outstrip the installation costs (even if I were prepared to have "trades" drill into my property with their "minimum viable effort to get the job done"..). Frankly, a friend went through an F-Gas course as it was cheaper than installation!

 

At the moment I'm a bit stalled on design. I have a ~45m2 floorplan with an 60% open-plan kitchen/living area, and a bedroom and a half -- do I need an implementation with a unit in each of the 3 spaces, or 2, single-splits or a multi-split (seems preferable just for finding places outside for the units). Or even a large emitter centrally located. With water it's somewhat easier to "whack in an extra radiator". I'd be interested if anyone has opinions or literature about effective placement of mini-splits.

 

Back-of-envelope calcs (heatpunk) think the heat loss at -2.4C is 2824W, -- that might be rather high based on some of the existing radiators 

 

 

 

[Crofter]

I did finally find, through a thread on here, that Appliances Direct sell them.

 

Like you, I'm considering various options including a single central unit vs multi splits. I put some layout drawings on my other thread.

[magnayn]

On 10/06/2023 at 13:14, Crofter said:

I did finally find, through a thread on here, that Appliances Direct sell them.

 

Like you, I'm considering various options including a single central unit vs multi splits. I put some layout drawings on my other thread.

I did find, after a tip from a friend that just F-Gas certified, that eBay has many vendors that sell units there that I haven't found often elsewhere (e.g: Samsung, but they're quite cooling rather than heating focussed).

 

On the "nonsense about A2A" thread, I was watching a YT video about air/air from a channel that's a A2W heat pump training organisation (heatgeek), where they talk to a guy that does commercial A2A. 

 

It was very notable half way through that the mask slipped. The real concern is that A2A is simple! If any old joe can get an F-Gas certificate, or fit units that don't require it - where then for over-complicated surveys (that bear little relation to reality as in old housing everything is a guess) and a closed-shop of "professionals" who can bamboozle the public with storage tanks and buffers and pumps and pipe sizes ?

 

This is lunacy. He was against ceiling fans (that americans in A2A setups use to push the air around) because... it might decrease the delta-T across the condenser and so lower the efficiency. I am without words. What's important isn't "are you comfortable in the room", it's overall efficiency apparently. So running practically 24x7 at a high efficiency (A2W) is preferable to a lower efficiency but more rapid time to comfort (A2A). Optimising for the wrong goal.

 

We have a heating market which is effectivelybeen  "do some simple sizing / gut feel for rads, upsize by 20%, install a boiler based on DHW demand, job done". If you need a PhD to correctly size an A2W system without it bankrupting the client then all is lost.

[DanDee]

1 hour ago, magnayn said:

What's important isn't "are you comfortable in the room", it's overall efficiency apparently. So running practically 24x7 at a high efficiency (A2W) is preferable to a lower efficiency but more rapid time to comfort (A2A). Optimising for the wrong goal.

 

We have a heating market which is effectivelybeen  "do some simple sizing / gut feel for rads, upsize by 20%, install a boiler based on DHW demand, job done". If you need a PhD to correctly size an A2W system without it bankrupting the client then all is lost.

 

When you know what you need, you buy what you need, when you don't know what you need, people like them are telling you what you "need".

 

The A/A works wonders for those that need it, and those that don't "need" it, want it ripped out because of the air blowing around.

 

Same with A/W, you don't need a PhD, you need UFH on all floors and to size the A/W over the minimum required.

[joth]

On 10/06/2023 at 11:18, magnayn said:

In my own case I cannot see the VAT saving would outstrip the installation costs (even if I were prepared to have "trades" drill into my property with their "minimum viable effort to get the job done"..). Frankly, a friend went through an F-Gas course as it was cheaper than installation

 

To zero-rate the VAT the installation must be at least 40% of the total bill. So yes, on a zero rated supply & install,  instead of +20% VAT you'll pay minimum of 166% of the price of all the materials.

 

 

[sharpener]

Hmm, let me see if I have got this right...

 

If the HP and parts cost £7500 you either pay £9k inc VAT for supply-only, or a min of £5k of installation on top and no VAT so £12k5 in total.

A penny less and you have to pay a shade under £15k inc VAT.

 

Conversely if the installation costs are only £2917 then even with the VAT due the total is also £12500.

So there is a "dead zone" of installation costs between £2917 and £5000 where the endprice is in fact disadvantageous to you. And I am sure that is one reason why installation never costs less than £5k though I can think of others.

 

[Dave Jones]

MCS scammery.