British Gas heat pumps - some restrictions on their offering FYI

[Beelbeebub]

32 minutes ago, JohnMo said:

You can also make from water, with electric, Scotland is currently 95% renewable energy, with loads more on the way, that excess electric can be used to make green hydrogen. Almost run like a PV immersion diverter, excess electric, hydrogen making process starts.

Yes different discussion but the route "renewable electricity -> hydrogen -> boiler -> heat" is several times less efficient than "renewable electricity -> heatpump-> heat". Scotland would genuinely be better off providing 3 bar electric fires to heat than hydrogen boilers.

 

 

[Beelbeebub]

58 minutes ago, JohnMo said:

Or would a bigger % drop in gas consumption come from.

 

Setting up and mandating the following on all boilers

1. Running weather compensation

2. Priority hot water or X plan

3. Sorting zone control, so boilers cannot short cycle. Simple logic controller so min flow rate through system is alway maintained - regardless of what an owner tries to do make it run crap.

 

Would instantly decrease consumption by 20%+ in most installed boilers.

I don't think it would.

 

1. There are alot of boilers installed that can't do weather compensation.

2. There are a lot that can't do this either - at least in a way that improves efficiency.

3. Yes heating controls are a mess, but I'm it sure boiler short cycling is major issue efficency wise other than it indicates you are running at higher than needed temps.

 

Even then, the most optimised boiler and system can only approach 95% efficency.

 

Unless you screw your HP install up badly (have flow temps over about 55C or lots of cycling) your overall efficiency (gas to heat, via operation and grid) will be 100%.

 

And that's before you factor in the decarbonisation of the grid. It doesn't matter how efficient you gas boiler is, it's really hard to run it on anything other than gas (it's not even easy to run it on hydrogen)

 

Fun fact I found out, 

 

10 years ago, the best the national grid ever achieved was above 400gCO2/Kwh, and was often over 500.

 

Now the worst week we've had this year is under 250 and we've been aslpw as 100 (week 12)

 

For reference a gas boiler hits about 200gCO2/kWh.

 

So all those heatpumps, even the really badly installed ones, are massively ahead of gas in carbon terms. We're nearly at the point where a 3bar fire beats a gas boiler!

 

Of course, if we do a massive switch to HPs our elec demand will rise, probably quicker than we can add renewables.  But we can still just build some CCGT stations, burn the gas we would have burnt in our boilers and end up ahead.

 

[HughF]

5kw Samsung with PWM pump doing a DHW cycle into a 1m2 coil.... The 150ltr slimline Vaillant HP cylinders that were £500 on ebay last year (I've got one waiting to go in, driven by a CE iVT-9)...

 

Just for relevance to the thread...

 

This is Glyn Hudson's DIY install, plenty of details on his YouTube channel. Replaced an LPG combi...

Edited August 2, 2023 by HughF

[JohnMo]

1 hour ago, Beelbeebub said:

Even then, the most optimised boiler and system can only approach 95% efficency

That is incorrect

 

I was doing between 105 and 110% eff overall. That was verified by certified heat meter. Combi boiler, with preheat on DHW, big buffer (doing the water preheat and UFH) and running a combination of WC and floor buffering via UFH.

 

If boiler cannot do the required functions it could be replace foc.

1 hour ago, Beelbeebub said:

Unless you screw your HP install up badly (have flow temps over about 55C or lots of cycling) your overall efficiency (gas to heat, via operation and grid) will be 100%

Plenty on here would verify the issues are common place, with rubbish installs.

 

I know you are fixated on ASHP being the only technical solution, but there could be many.

 

 

[sharpener]

11 hours ago, TonyT said:

Decent gas boilers sized  correctly with hot water priority and weather compensation would be an option if you are sticking with gas.  More efficient than s or y plan

 

I understand why even with weather comp S-plan is less than optimal because you then feed the CH at the HW flow temp. But Y-plan?

 

FWIW the HP would replace a 28 y/o oil boiler. We currently have its stat set to the min which is 65C. Weather comp not possible because this would result in acid condensate all the time. It has an economiser in the flue and this produces a small amount on startup, the condensate tray has been replaced twice as it is.

 

4 hours ago, DanDee said:

If it's not the low COP that would drive you crazy, the reheat time will do for sure with a minuscule coil.

 

No, since the HP will increase the flow temp until it can get rid of the heat, the reheat time will be no worse than before. 6kW min o/p from an HP will still be twice as fast as the immersion heater. In any case it is not a consideration for us, the 210 l tank only needs heating once in 24h, atm entirely by PV.

 

3 hours ago, markocosic said:

For some, it's because they're planning to sell within the product lifetime and the new buyers wouldn't value the energy efficiency measures. (I'm in that boat)

 

For others, it's because they're not credit worthy/are already living beyond their means, so can't borrow the money now to save themselves money later.

 

For others, it's simply that they're mean, and have access to the money, but don't want to spend it on heating and hot water.

 

Most owner occupiers are in group 1 or 3.

 

No, the objections I have to replacing an OSO s/s tank in good working order are none of the above:

 

(i) massive disruption in order to dismantle and rebuild the airing cupboard, and lift carpets and flooring to run new pipework

or site new tank in utility room meaning there is no space for the thermal store I also want (which will fix the turn-down problem anyway as it will be a parallel sink for the heat)

(ii) cost thereof vs the small marginal savings given electricity is E7 night rate or free PV

(iii) waste of resources in scrapping off a tank prematurely

(iv) it is an unthinking brute force approach which totally lacks elegance in its design.

[Beelbeebub]

12 minutes ago, JohnMo said:

That is incorrect

 

I was doing between 105 and 110% eff overall. That was verified by certified heat meter. Combi boiler, with preheat on DHW, big buffer (doing the water preheat and UFH) and running a combination of WC and floor buffering via UFH.

 

If boiler cannot do the required functions it could be replace foc.

That is an extremely well set up system. It can only achieve the apparent the high efficiency because the UFH g WC provide very low return temps to allow maximum latent heat extraction.

 

If you were to use a modern HP on such a set up (when the current boiler expires) you would need a DHW tank, so would fit a large coil model and, alongside your low flow temp heating, would be getting efficencies of 150%+ (with respect to the base gas)

 

A modern HP will, in most cases, burn less gas for the same heat output than a boiler attached to same system.

 

Yes, some really bad systems with tiddly little rads that need 75 or 80C flow temps just to keep you warm enough, will need upgrading because they won't reach a.SCOP over 2.5

 

But if your system can run flow temps below 55C, you will almost always end up with less gas burn via HP

 

[Beelbeebub]

21 minutes ago, JohnMo said:

Plenty on here would verify the issues are common place, with rubbish installs.

 

I know you are fixated on ASHP being the only technical solution, but there could be many.

Yes, plenty of rubbish installs, especially the older ones with r410a and badly sized (over or under)

 

But yes I am fixated on ASHPs as the main (not only) solution, because they are.

 

Sure, some people will still be on oil or gas or electric for various reasons (unusual location, unusual usage patterns, unusual buildings etc) but the vastajority of houses, flats, offices etc could swap over from gas boilers to HPs. Not always air source and not always air to water (UK moving straight to A2A systems is an option) but given our infrastructure and preference for wet heating systems A2W ASHPs will be the default choice, like a combi gas boiler is often the default now and if not a combi then a boiler and UVC.

 

But if we want to reduce our carbon output the gas boiler has to go. There is no way we can get a combustion boiler to emit much less than 200gCO2 per kWh*. Many emit more.

 

HPs can already get below that value and as the grid decarbonises the figure drops lower and lower. Already a well setup HP running on a good day for our grid will emit less than 25gCO2/kwh

 

The funny thing is we already had a huge stimulus subsidy that was pretty effective with the boiler scrappage scheme. People had old boiler ripped out, and got cash towards a new boiler.

 

We need a similar setup to boost our heating fleet's efficency again.

 

The current scheme isn't working. Our rates are slow.

 

*Theoretically we could if we used Hydrogen, and central carbon capture for any H2 made with gas, but if you examine the logistics of that route it's clear it is pure fantasy, whose only purpose is to delay the switch from combustion boilers.

 

 

[Beelbeebub]

3 hours ago, JohnMo said:

 

Stop grants for heat pumps - only funding the well off at the moment, not everyone

This is my point. The current system makes HP installs expensive so this charge is leveled at them 

 

(I'll be honest, I think some of this is down to the current political climate and culture wars - some wish to stop all progress on the climate front and it is convenient to use "but what about the poor working class salt of the earth bloke?! - all this climate stuff is for middleclass metropolitan tofumunching wokerati!" attack line.)

 

The idea is to make swapping to a HP, which is good for society, also good for the majority of people.

 

At the moment we are trying to make a change good for all of us at a national and global level whilst making it hard on an individual level.

[JamesPa]

48 minutes ago, sharpener said:

No, the objections I have to replacing an OSO s/s tank in good working order are none of the above:

 

(i) massive disruption in order to dismantle and rebuild the airing cupboard, and lift carpets and flooring to run new pipework

or site new tank in utility room meaning there is no space for the thermal store I also want (which will fix the turn-down problem anyway as it will be a parallel sink for the heat)

(ii) cost thereof vs the small marginal savings given electricity is E7 night rate or free PV

(iii) waste of resources in scrapping off a tank prematurely

(iv) it is an unthinking brute force approach which totally lacks elegance in its design.

+1 on this analysis. 

 

Plus the annual cost of a G3 service (which wipes out the cost saving on energy) + given (iv) it's surely likely that a more elegant solution will appear in the next few years (eg a bolt in phe/pump).

 

 

[JohnMo]

31 minutes ago, Beelbeebub said:

you were to use a modern HP on such a set up (when the current boiler expires) you would need a DHW tank, so would fit a large coil model and, alongside your low flow temp heating, would be getting efficencies of 150%+ (with respect to the base gas)

 

A modern HP will, in most cases, burn less gas for the same heat output than a boiler attached to same system

I have now installed an ASHP, the buffer is still there with PHE and circulation pump, to increase exchange area. The buffer is a repurposed vented 160L thermal store, I heat it to just over 40 degs with ASHP, it actually settles out at close to 50, with max flow rate from ASHP of 55, but it doesn't give much useful quantities of hot water, nightly washing up and one shower, the next morning using return circulation the taps are warm which is fine. It is also charged via immersion with excess PV, was sat at 80 degs yesterday. A bad day I use 2kWh of gas, many days no gas. So boiler is still there for DHW only. It's only 2 years old to loathed to chuck it just yet.

 

UFH is by ASHP only and is now a single zone, no buffer, no mixer or any secondary pumps. As simple as it can be. Has worked well in the summer on cooling duty, using self generated electric (PV). Couldn't be greener.

[Beelbeebub]

50 minutes ago, JohnMo said:

I have now installed an ASHP, the buffer is still there with PHE and circulation pump, to increase exchange area. The buffer is a repurposed vented 160L thermal store, I heat it to just over 40 degs with ASHP, it actually settles out at close to 50, with max flow rate from ASHP of 55, but it doesn't give much useful quantities of hot water, nightly washing up and one shower, the next morning using return circulation the taps are warm which is fine. It is also charged via immersion with excess PV, was sat at 80 degs yesterday. A bad day I use 2kWh of gas, many days no gas. So boiler is still there for DHW only. It's only 2 years old to loathed to chuck it just yet.

 

UFH is by ASHP only and is now a single zone, no buffer, no mixer or any secondary pumps. As simple as it can be. Has worked well in the summer on cooling duty, using self generated electric (PV). Couldn't be greener.

Sound like a good setup.

 

The heating side is, more.or.less the way forward.

 

If (probably when) I do another build, I think I'll go for a HP feeding single zone UFH (it'll prob be a bungalow given other restrictions) with a diverter to a hot water cylinder. Prob unvented, though maybe vented with pump.  I don't think I'll use a thermal store just because of the extra temp/volume needed.

 

Only one pump, one valve. Weather compensated flow temps with thermostat high limit.

 

Question, if your boiler had some sort of catastrophic, not under warranty failure.....would you replace it?  Do you use gas anywhere else? Eg hob?

[JohnMo]

1 hour ago, Beelbeebub said:

Question, if your boiler had some sort of catastrophic, not under warranty failure.....would you replace it?  Do you use gas anywhere else? Eg hob?

No other gas, would just replace with UVC.

[Beelbeebub]

25 minutes ago, JohnMo said:

No other gas, would just replace with UVC.

Electric or HP? 

[sharpener]

2 hours ago, JamesPa said:

Plus the annual cost of a G3 service

 

You've mentioned this before, I am not sure it is mandatory to pay a third party to do it, what is the basis for yr thinking it is? For those paying for an annual boiler "service" it is a trivial amount of additional work and I think routinely included.*

 

Just looked it up, my UVC mfr (Ariston) says the following should be done annually by a "competent person". Hard to argue a degree in physics is not sufficient(!):

 

Clean the filter screen in the PRV, test the pressure vessel pressurisation and the temp and pressure relief valves, check that the drain pipes (D1 + D2) run clear. Check the pressure reduction valve works OK by measuring the pressure at a draw-off point (I doubt the professionals ever do that, if the spring in it fails [which has happened to me] flow/pressure will be catastrophically low anyway).

 

I test the valves more like 4 times a year as by repute they have a tendency to not re-seat properly if not used in a long time.

 

*Not that they do any work! This is another racket, Domestic and General which underwrite a big proportion of maintenance contracts admit that their policies only cover an annual inspection and they do not carry out the service procedures recommended by the boiler mfrs.

[JohnMo]

27 minutes ago, Beelbeebub said:

Electric or HP? 

HP, big coil cylinder.

[JamesPa]

17 minutes ago, sharpener said:

You've mentioned this before, I am not sure it is mandatory to pay a third party to do it, what is the basis for yr thinking it is? For those paying for an annual boiler "service" it is a trivial amount of additional work and I think routinely included.*

 

Just looked it up, my UVC mfr (Ariston) says the following should be done annually by a "competent person". Hard to argue a degree in physics is not sufficient(!):

Fair enough. I will drop mentioning this unless I can find proof of requirement somewhere.

 

Having said that the average householder might not be 'competent', so as a general point in relation to how not to sell ashps the point arguably still stands.

Edited August 2, 2023 by JamesPa

[Beelbeebub]

17 minutes ago, JohnMo said:

HP, big coil cylinder.

Sensible.

 

But the point is your system is incrementally improving. Right now it is good enough and will no doubt get even better.

 

Imagine if it was all or nothing. No halfway house, see how it goes, tweak a bit more, replace stuff as it ages out. Just do it all in one go because otherwise it won't be efficient enough.

 

We need to make your approach easier (normal even). Support it where required (IMHO, via a price guarantee subsidy for a.limited time).

[Beelbeebub]

37 minutes ago, sharpener said:

You've mentioned this before, I am not sure it is mandatory to pay a third party to do it, what is the basis for yr thinking it is? For those paying for an annual boiler "service" it is a trivial amount of additional work and I think routinely included.*

 

Just looked it up, my UVC mfr (Ariston) says the following should be done annually by a "competent person". Hard to argue a degree in physics is not sufficient(!):

As I was responsible for several.UVCs I can answer this.

 

We had an issue with a cylinder, basically the PRV activated and the tundish leaked, it is a design flaw with the common tundish design, water can track down the arms to the outside.

 

We have a suspicion the tenant was fiddling.

 

Anyway, the arse covering recommendation from on high (the manufacturer's and insurers) was we needed someone with a g3 ticket to insect every year. This meant our regular company had to send thier one g3 ticket guy to do the annual boiler services. Rather than any of the regular gas safe guys who had been doing it (mostly they fit combis for us)

 

This was a fact that led us to ditch UVCs where.fitted and go with combis and vented.

[Beelbeebub]

I should add that even the g3 guy thought it was daft, the check was just a check of the expansion vessel then a visual check of the valve and pipework.

 

Could be done by anyone with eyes and a foot pump.

 

Every single home owner I know with an UVC has it inspected. Several didn't even know they had an UVC. One didn't even know where the cylinder was!

 

 

[sharpener]

54 minutes ago, JamesPa said:

Fair enough. I will drop mentioning this unless I can find proof of requirement somewhere.

 

Having said that the average householder might not be 'competent', so as a general point in relation to how not to sell ashps the point arguably still stands.

 

Well yes, I have no idea what happens with the average domestic install, I suppose it is done with the boiler "service" or not at all. Your case is a bit unusual in that you have a recent vented installation,@Beelbeebub has many for reasons above.

 

In a commercial setting I am not surprised a G3 ticket is an insurance requirement (though the course is not that expensive). If there is a suspicion of tenants fiddling with the system then it might need someone with a G3 ticket who knows what he is looking for to spot that.

 

I am not a professional landlord but in the past when I rented a flat out nothing surprised me, best was a tenant who wanted me to pay for an electrician callout, turned out he admitted to knocking the standard lamp over and the bulb blowing also tripped the RCD, muppet!

13 minutes ago, Beelbeebub said:

Every single home owner I know with an UVC has it inspected. Several didn't even know they had an UVC. One didn't even know where the cylinder was!

 

How did they know to get their (unknown) UVC inspected then? Or was it bc you put them all straight <g>?

 

26 minutes ago, Beelbeebub said:

We had an issue with a cylinder, basically the PRV activated and the tundish leaked, it is a design flaw with the common tundish design, water can track down the arms to the outside.

 

Yes, the concept of the tundish is pretty rubbish, at full flow from the relief valve it splashes out of the cheapo plastic ones and goes everywhere. Since they are usually tucked away somewhere the idea that the overflow will quickly come to someone's attention is risible.

 

My D2 pipework was installed by G3 qualified person and is fully compliant regarding size vs length, but still will not quite take the full flow when I test it without backing up to the tundish and overflowing, and that is after I had to relocate the bladder trap myself - before which it was much worse.

 

 

Edited August 2, 2023 by sharpener

[Beelbeebub]

48 minutes ago, sharpener said:

How did they know to get their (unknown) UVC inspected then? Or was it bc you put them all straight <g>?

 

Just seen! It's a typo!😁🫢

 

Should read

 

"Every single home owner I know with an UVC hasn't had it inspected. Several didn't even know they had an UVC. One didn't even know where the cylinder was!"

 

Basically, apart from me, getting inspections because it's a legal requirement, nobody in private homes seems to be - alot of people don't get their boiler serviced every year.  Most people are oblivious

[Beelbeebub]

54 minutes ago, sharpener said:

Yes, the concept of the tundish is pretty rubbish, at full flow from the relief valve it splashes out of the cheapo plastic ones and goes everywhere. Since they are usually tucked away somewhere the idea that the overflow will quickly come to someone's attention is risible.

 

My D2 pipework was installed by G3 qualified person and is fully compliant regarding size vs length, but still will not quite take the full flow when I test it without backing up to the tundish and overflowing, and that is after I had to relocate the bladder trap myself - before which it was much worse.

Problem we had is at very low drips, the water tracked from inside to outside around the arms between the top and bottom halves. It's really poor design, there is no drip feature on the top part of the tundish. Little drips will track down the arm.  I modified them by drilling the top "end stop" out and inserting the copper pipe just a few mm further into the tundish so there was a sharp drip feature.

 

And yeah, the pipework can't take full flow. But, in fairness, I don't think they are supposed to. The PRV isn't a blow off valve, all or nothing.  It's supposed to "crack" open and allow a dribble of water out, thus bleeding energy. In theory it only needs to bleed a flow rate equivient to the energy input and delta between incoming mains and activation temp.

 

Even a 30kw boiler jammed on full power would only require 5lpm to stay cool.

 

It was part of why we suspected the tenant was playing with the valve. The second time it happened it was an overflow because the valve had opened so far and was stuck on the little "detent" before it snaps back.  The resulting flow overwhelmed the tundish pipework and flooded the floor.  The floor which the tenant stacked lots of "priceless" papers that he forbade me to move our of the standing water when I arrived.  Neither I, the G3 guy or the valve manufacturers could envisage how the valve could be activated to that level of opening without manual intervention.

 

The tenant claimed against our insurance for damage to the papers and items (despite me having written to him previously to warn him not to store items next to the tank).

 

Luckily I had all the communications, and testimony from the manufacturers, engineers etc

 

His claim was denied. 😁

[JamesPa]

4 minutes ago, Beelbeebub said:

Problem we had is at very low drips, the water tracked from inside to outside around the arms between the top and bottom halves. It's really poor design, there is no drip feature on the top part of the tundish. Little drips will track down the arm.  I modified them by drilling the top "end stop" out and inserting the copper pipe just a few mm further into the tundish so there was a sharp drip feature.

 

And yeah, the pipework can't take full flow. But, in fairness, I don't think they are supposed to. The PRV isn't a blow off valve, all or nothing.  It's supposed to "crack" open and allow a dribble of water out, thus bleeding energy. In theory it only needs to bleed a flow rate equivient to the energy input and delta between incoming mains and activation temp.

 

Even a 30kw boiler jammed on full power would only require 5lpm to stay cool.

 

It was part of why we suspected the tenant was playing with the valve. The second time it happened it was an overflow because the valve had opened so far and was stuck on the little "detent" before it snaps back.  The resulting flow overwhelmed the tundish pipework and flooded the floor.  The floor which the tenant stacked lots of "priceless" papers that he forbade me to move our of the standing water when I arrived.  Neither I, the G3 guy or the valve manufacturers could envisage how the valve could be activated to that level of opening without manual intervention.

 

The tenant claimed against our insurance for damage to the papers and items (despite me having written to him previously to warn him not to store items next to the tank).

 

Luckily I had all the communications, and testimony from the manufacturers, engineers etc

 

His claim was denied. 😁

The thought of a UVC in a rental property gives me the screaming heebie jeebies.  The tenants will only report something wrong when leaking water has done major damage or if there is an actual explosion.  Avoid in my book.

 

Probably this is an excellent argument for heat pumps as opposed to boilers in rental properties.  Gas can explode, properly installed electrics are pretty much idiot proof.

[Beelbeebub]

42 minutes ago, JamesPa said:

The thought of a UVC in a rental property gives me the screaming heebie jeebies.  The tenants will only report something wrong when leaking water has done major damage or if there is an actual explosion.  Avoid in my book.

 

Probably this is an excellent argument for heat pumps as opposed to boilers in rental properties.  Gas can explode, properly installed electrics are pretty much idiot proof.

Yeah, we switched out all the UVCs (we didn't have many) after that. Went to combis and in the case of electric places, electric showers and vented cylinders.

 

It's also why I'm thinking of doing heat only HPs for the electric flats and leaving the existing cylinder/shower arrangement. 

 

Any future upgrade would be to vented tank heated by large coil and if pressure is an issue, a pump.

 

The combi flats and houses are tougher.  But almost all did have a tank at one point, so it would be possible to refit one. Probably go with vented and pumped.

Edited August 2, 2023 by Beelbeebub

[markocosic]

9 hours ago, HughF said:

This is Glyn Hudson's DIY install, plenty of details on his YouTube channel. Replaced an LPG combi...

 

Hmmm!

 

 

Thoughts out loud:

 

 

This is:

 

- A 6 kW could input from a standard "low temp" F-Gas heat pump 

 

- A cylinder setpoint of 42 degC, which best case gives 150 litres of shower water (allowing for some destratification), and then reheats at 6 kW

 

- And a NEW cylinder with decent insulation but perhaps more importantly a completely clean 1m2 coil that runs halfway up the cylinder.

 

Looks like it works nicely; heat pump wise; and it'll also have low standing heat losses etc. I'm sold on this being a functional option 

 

The capacity is miniscule though due to the temperature it is being operated at. Works for a self confessed hair shirt. I perhaps wouldn't want to be the father selling this to a wife and 2.4 long haired daughters though. I would roll my eyes at it if buying the place.

 

If it were a more modern heat pump you could perhaps have 50C for the same COP; if reheated at the same rate. Still a relatively low capacity cylinder.

 

 

Now to the "miscellaneous old cylinder" option for a "typical retrofit" (rather than a brand new cylinder, purchased independently of the heat pump, either for reasons of necessity or due to poor planning)

 

It's for sure gonna have higher heat losses.

 

What is the coil? 0.6 m2 is quite different to 1.0 m2. Is it in the bottom of the cylinder only (trying to stir the thing up using convection currents) or does it extend through more of the cylinder? Is it clean, or has it been heated to 80C in the southeast of England and is there the usual 20 of scale on the coil / in  the  bottom of the cylinder? Was it ever big enough at 60C? Is it gonna be big enough at 42C or 50C? Did you want an invented to sack off all the roof tanks and pumps etc?

 

Given the small material cost of a cylinder vs a paid heat pump install, and the opportunity to get it all without VAT, would you be daft not to swap it? Probably.

 

Retail (what the fitter would charge) on those slimlines is 1165+VAT

https://midsummerwholesale.co.uk/buy/vaillant-heat-pumps/vaillant-cylinder-150l

 

Retail on the biggest baddest cylinder in that range is 1605+VAT

https://midsummerwholesale.co.uk/buy/vaillant-heat-pumps/vaillant-cylinder-300l

 

Some will say fuggit; do it. I think this is the reality of anybody serious about an upgrade.

 

 

Some will ask to reuse an old piece of shite with the potential to be a scale filled liability that was last touched by the fitter etc. Or cause complaints due to low stored volume.

 

The fitter will say naah, not worth the risk.

 

 

Now say the cylinder is relatively new. Say it might / will probably actually work.

 

If fitters are looking for work, and price is a consideration, they might entertain taking the time to check if they can use that and the risk of touching it last.

 

Reality: they're not looking for work. Demand exceeds supply. They're going to choose the jobs which pay the most. If you're interested in a new cylinder you'll get a fair price for a new cylinder. If you're not interested in a new cylinder you're going to get much the same price.

 

This only changes once supply exceeds demand.

 

 

The big boys and girls have additional constraints. BG evidently won't install ANYTHING other than in accordance with the manufacturer's backside covering instructions. Fitters won't get the leeway.

 

 

You can't DIY this because of the f**king MCS cartel. Not just the grant. It's not even legal. (planning)

 

Nor can you MCS space heating only. Not grant eligible.

 

And that's perhaps the kicker. Don't blame the installer for wanting to include hot water. They're obligated to otherwise the job costs £5k more. And if they're gonna do hot water to get the grant - you automatically increase costs by £5k by not doing hot water - to then they think you're daft for not going all out on maximum performance and pleasure and resale value, but perhaps can't articulate this in the best way?

 

I think MCS are f**ks and HMG are fools for promoting them. Just in case that wasn't clear before!

 

 

Octopus are known to be targeting 90s Barratt estates. Where there are 30 year old vented cylinders in houses due for their first bathroom swaps/cylinder swaps etc. And much of the heating was still large bore copper. Probably not accidental?