Heat Pumps, One for the engineers

[Dormouse]

Yes, cast iron, if thickly cast, is a thermal mass but not that great at retaining heat long term. Sheet steel, as in modern radiators, is not. A stone/concrete insulated floor is better at heat retention and can be heated at lower temperatures - typically 30 - 40`C.

[Stickyfinger]

They "fit" into a modern house very well, get the colour correct and choose a good design and they are far better than the designer stuff people fit these days....they are not just "old school" designs you know


The weight is not a problem....it is not that much and they are always close to a wall (remember they have feet.

Yes, it is the convection that matters....long slow heat release...

[CitroJim]

They "fit" into a modern house very well, get the colour correct and choose a good design and they are far better than the designer stuff people fit these days....they are not just "old school" designs you know

In that case, when I remodel my lounge and hallway I'll commission you to build me some Alasdair Getting them here in the back of an AX might be a challenge

And they'll be sitting on concrete floors...

[mickthemaverick]

And they'll be sitting on concrete floors...

That surprises me Jim, I thought your remodelling would include AXminster carpets throughout!!

[xantia_v6]

To give a different perspective on heat pumps (I know that this is an unusual installation compared to the average UK house) our house in New Zealand was built 25 years ago with solid concrete floors and walls with a skin of insulation on the outside of the walls.

The floors were made with heating pipes in the centre of the 100 mm slab. For the first 24 years the floors were heated by a little 15kw electric boiler running on cheap night rate electricity, with the floors and walls having enough thermal mass to ensure that it is rare to require any daytime heating.

Last year I replaced the electric boiler with a 16 kW air to water heat pump. 9 kW would have been sufficient, but this one was cheap as it was surplus from a commercial construction project. The nice thing about under floor heating is that it does not require much temperature in the water, never more than 35 degrees here, typically 30. So with an ambient temperature that rarely drops below 5 degrees, never below 0, the over-size heat pump should easily be getting an average COP better than 4.5.

And the best thing is that electricity here is 100% hydroelectric and (night rate) still only 7p (UK currency) per kWh. So heat is only costing 2p per kWh. The worst thing is that we usually spend (the southern) winter in the northern hemisphere.

[CitroJim]

And they'll be sitting on concrete floors...

That surprises me Jim, I thought your remodelling would include AXminster carpets throughout!!

New carpet for me is a difficult choice as it must be suitable for a lounge but as my lounge is also a busy thoroughfare between the front door and the only access to my garden and workshop back door it needs to be tough enough to resist oil, mud and bike traffic...

Something industrial I think... Difficult...

Interesting on the Kiwi heat pumps Mike... I once lived in a flat back in the mid-70s with electric underfloor heating. It kept a nice background warmth going but needed assistance from a conventional electric heater when really cold... No idea how much it cost to run as it was all included in the rent...

I believe such systems are now quite often specified in bespoke new builds but retrofitting is a bit of an issue unless doing a big refurb. job... Seems a popular option for barn conversions - no doubt financed by all the 'barn find' cars found in said barn before it was made habitable!

[Stickyfinger]

Forget about under floor in you place Jim the work/cost are way to disruptive/high. Stick to a "wet" system.

Laminate floor and a large carpet (Wilton naturally) in the living room area ?

[Gibbo2286]

How good is this modern stuff?
https://www.bestheating.com/milano-alph ... src=aw.ds

[CitroJim]

Laminate floor and a large carpet (Wilton naturally) in the living room area ?

That's what I'm thinking Alasdair... Maybe a carpet of the same quality as found in a night club - minus the hideous garish patterns I seem to recall they came in. Was that to stop the punters nicking them?

How good is this modern stuff?
https://www.bestheating.com/milano-alph ... src=aw.ds

I must admit I rather like the looks of those Eric For rooms other than the lounge and hall. Definitely trad. cast iron for those locations... They'll go well with my grandfather clocks

[Peter.N.]

Axminster is where we do our shopping.

Peter

[CitroJim]

Axminster is where we do our shopping.

When I was little I always imagined Axminister to be covered entirely in carpet... For all I know it may well be as remarkably, I've never been there...

Can you confirm one way or another Peter?

[Peter.N.]

It used to be covered with the Aminter carpet factory Jim, practically everyone worked there in the '70s but its gone bust and been rescued at least twice since we have been here, I believe it is still making carpet but on a much smaller scale than formally. Nice little country town though. You see it on 'Escape to the country' very often, when they come to East Devon they usually show it. They do have a showroom on the Seaton road (the carpets that is).

Peter

[Peter.N.]

I have just been looking at the hydrogen video posted by Myglaren and the situation is even worse than I thought, I had no idea precious metals were involved as two bits of wire with voltage across them stuck in a glass of water will produce hydrogen.

I would think that the power needed to produce hydrogen by hydrolysis could well be greater than the power the fuel produces. The only place I know that makes hydrogen by electrolysis is Orkney where they have an excess of green energy and even export some to the mainland. Can't see it ever being viable myself - unless there is a remarkable breakthrough.

Peter

[bobins]

Government green heating scheme off to slow start

"A major new grant scheme to replace gas boilers in England and Wales has got off to a slow start, government figures released on Thursday show.
Under The Boiler Upgrade Scheme households can apply for vouchers to help them switch to a heat pump.
The government aims to give out 30,000 vouchers annually but only managed 9,888 between the scheme's launch in May and the end of the year.
Since May last year households across England and Wales have been able to apply for a £5,000 voucher to replace their boiler with a more environmentally-friendly heating system.
The government set aside £450m for this scheme, and said it would fund 90,000 pumps over three years.
Based on new figures released on Thursday, at the current rate, by March 2025 when the scheme is due to end only 42,000 vouchers would be issued."

More at the Beeb: https://www.bbc.co.uk/news/science-environment-64414493

[Dormouse]

Out of curiosity, I applied to a scheme for such a green exchange. Where is the firm based? Market Harborough. Not East Kilbride or even Eyemouth. My nearest installer is Market Harborough!

Anyway, I have been doing rough calculations for my house and I have found that over the last month, as an example, a ATW Heat Pump would have needed to have achieved a COP of 3.3 to cost the same as my gas system. Now, trying to find the engineer's calculations to achieve this was all but impossible in the UK. But, go to Canada and not only do you get all the information you need but you also find a set of disturbing conditions.

The nail in the coffin is the very last paragraph.

It is recommended I retain my existing heating to top up the shortfall!!!!!!


This is from a company that relatives in eastern and western Canada know of and is rated as an OK firm but I only got this information from their Engineer's Manual which in Canada is a lot more readily available than the UK.