I always thought heat pumps were expensive waste of time

[Resu]

ASHPs aren't the best solution for every house but that doesn't mean they don't have their place. Here in the north of Scotland there aren't many places outside of Inverness that have mains gas.

The video is correct in that they are not suitable for many older houses but in new builds they can work well, especially when paired with UFH. In small houses the air-to-air units can even work quite well.

 

[pirate]

Dylan had double vision, totally related to alcohol consumption. now pirate is suffering similar symptoms: double posting. put that neat rum down. ??

quadruple vision, Tel?

 

[telectrix]

wasn't me . the forum went ---- up. even still insisting on 50 characters in a post

 

[Simon47]

... but in new builds they can work well, especially when paired with UFH.

? ? ? ? ?
"Can" being the operative word.
Yes, if the house builder builds something well insulated, puts UFH in (especially in the otherwise cold block of concrete they tend to have as a ground floor), then a heat pump will probably work well. But as long as they carry on with the attitude of "doing it this way will save us 2d, so we'll do it this way" then we'll carry on getting new houses where HPs aren't going to work well.
They aren't going to fit UFH because it costs more than fitting a rad. They aren't going to fit an oversized rad because fitting the minimum size the figures suggest might work is cheaper. They aren't going to fit passivhaus standard insulation because that costs more than fitting the minimum the BRs (building regs) allow them to get away with - if they even fit it (c.f. a program on TV a few years ago where a big name housebuilder didn't even fit the roof insulation, it was still in rolls in the attic, and they had to take roofs off to fit it).
The quickest and simplest win for new builds would be to simply tighten up the BRs to need better thermal performance - then new builds would become better performing.

 

[Vortigern]

In fact in the new build we just completed, we came in a few days in after completion and there was a massive amount of water leaked. It turns out it was from condensation from above the insulation. It then transpired the "architect" got it wrong in the method of installing it. Cue, major work. I mean if you can't even get that right in a new build.......what hope?

 

[brianmoooore]

I have been bombarded recently with leaflets urging me to replace my old storage rads with new, high-efficiency ones.

The efficiency of new electric heaters is exactly the same as ancient ones, at precisely100%.
The controllability, in terms of when they release that heat, is a different matter.

I've had an air to air heat pump in service for about ten years, in my conservatory. Works well in cold weather, but in VERY cold weather it struggles. At these times the heating requirement is higher, and the units heat output drops right off.

 

[Resu]

? ? ? ? ?
"Can" being the operative word.
Yes, if the house builder builds something well insulated, puts UFH in (especially in the otherwise cold block of concrete they tend to have as a ground floor), then a heat pump will probably work well. But as long as they carry on with the attitude of "doing it this way will save us 2d, so we'll do it this way" then we'll carry on getting new houses where HPs aren't going to work well.
They aren't going to fit UFH because it costs more than fitting a rad. They aren't going to fit an oversized rad because fitting the minimum size the figures suggest might work is cheaper. They aren't going to fit passivhaus standard insulation because that costs more than fitting the minimum the BRs (building regs) allow them to get away with - if they even fit it (c.f. a program on TV a few years ago where a big name housebuilder didn't even fit the roof insulation, it was still in rolls in the attic, and they had to take roofs off to fit it).
The quickest and simplest win for new builds would be to simply tighten up the BRs to need better thermal performance - then new builds would become better performing.

When I said new build I didn't mean the usual "thrown up in the hundreds", Persimmons type of thing. Fortunately nothing of scale happens up here aside from local authority stuff.

I meant single house sites, private homes, self builds & the like. Little to no corners cut by most of the builders around here as it's not a massive community and generally speaking they rely on reputation so it isn't long before the rogues are outed!

 

[telectrix]

i can't get my head round how they work. you suck in air at 5 deg.C., magic it, and it comes out at 20 deg.C. has to need a large amount of leccy or witchcraft to do this.

 

[Dustydazzler]

i can't get my head round how they work. you suck in air at 5 deg.C., magic it, and it comes out at 20 deg.C. has to need a large amount of leccy or witchcraft to do this.

Sounds like a Fart

 

[James]

Basic theory is that you take air outside at say 8 degrees and cool it to say 7.5 degrees.
the point is that there is a LOT OF AIR that you are cooling outside.
if you cool a large amount of something, it releases a large amount of heat.
this heat is “pumped” inside the house and then released by blowing a SMALL AMOUNT OF AIR at a much higher temperature to warm the house.

it is proper thermodynamics blended with real life energy conversion from electricity to mechanical and can otherwise be described to others as WITCHCRAFT!!

 

[Vortigern]

@telectrix Think reverse fridge basically. Anyhoo, when I was younger we had these cast iron pyramids in the bathroom. They were about 1m height and had a base of circa 30cm x 30 cm. They were pretty, quite ornate and had a small candle sized flame at the base which heated the mass of cast iron which warmed the bathroom nicely and dried your towels. It was very very cheap to run. We also had gas fridges (gas evaporation system again small flame at the back), gas lights, and flatley clothe dryers. I still have a flatley clothes dryer electric heated cost zippo to run and warms the whole room you just can't get them like that anymore. We used to have gas hall heaters again pennies to run, and they got condemned by the gas board. They warmed all the hallway and upstairs landing again for pennies. No wonder they got rid of them all. Now there is your green energy. I would put those cast iron towel warmers against your heat pump and bet they would win on green things and money/cost. This save the climate thing is very disingenuous. We could easily burn gas to much better bang for bucks etc. The will is not there. When they realised we werent spending enough, they made us get rid of it, far too dangerous (cheap) to run!

 

[brianmoooore]

Take an ordinary fridge, take the door off, cut a fridge sized hole in an external wall of your house and foam the fridge in the hole, with the back of the fridge inwards.
You now have your very own air sourced to air heat pump.

 

[telectrix]

@telectrix Think reverse fridge basically. Anyhoo, when I was younger we had these cast iron pyramids in the bathroom. They were about 1m height and had a base of circa 30cm x 30 cm. They were pretty, quite ornate and had a small candle sized flame at the base which heated the mass of cast iron which warmed the bathroom nicely and dried your towels. It was very very cheap to run. We also had gas fridges (gas evaporation system again small flame at the back), gas lights, and flatley clothe dryers. I still have a flatley clothes dryer electric heated cost zippo to run and warms the whole room you just can't get them like that anymore. We used to have gas hall heaters again pennies to run, and they got condemned by the gas board. They warmed all the hallway and upstairs landing again for pennies. No wonder they got rid of them all. Now there is your green energy. I would put those cast iron towel warmers against your heat pump and bet they would win on green things and money/cost. This save the climate thing is very disingenuous. We could easily burn gas to much better bang for bucks etc. The will is not there. When they realised we werent spending enough, they made us get rid of it, far too dangerous (cheap) to run!

back in the 1960's the Clean Air Act came in. my dad had to have the coal fires replaced with gas fires, and shame, they took out the Rayburn smokeless fuel stove which also heated the water. kitchen and hall had flueless gas heates ; bedrooms had heaters on a flex pipe. forward a few years and natural gas came in. gas board condemmned all our heaters that they had fitted olny a few years gefore.

 

[PEG]

I thought his arguments biased and shallow of technical content. From a wet pants that wants to fit gas boilers.

Hi,by his own admission,it was a rant ?,and one based on his many years in the job.

I didn't notice any bias towards advising gas boiler fitting,just an overview of what he,personally sees,as the current state of affairs.

There was enough technical input, commensurate with a 'layperson' audience,such a video is aimed at.

Having been involved in many 'eco' labelled schemes,over the years,i wholeheartedly agree with his assertions,regarding mis-selling,grants,and how many of these ideas.are forced on people and projects,where they can only fail,thus,preventing take-up,where they are ideal.

Just for interest,i have a friend who had a PV install,at about the time the FIT were due to drop....he asked my advice,and on paper,it was hard to knock,but my concern was the roof. It needed capable craftsmen,to deal with fitting...it also could have done with pointing at the sun ?

Anywho....after a decade plus,of failed systems,poor output,liquidated companies (3 off),and much legal expense,we are repairing and renewing the roof....and the entire array will be going in a skip,or as we say,being 'recycled'.

Apart from this awful waste of money,time and resources,the biggest casualty will be my friend and his extended family,as they will shun any similar scheme,be it worthy or not.

 

[Simon47]

Oh, absolutely agree - I can see hoards of people polishing their snake oil display cases ready for this next "opportunity". Many of them will have no idea what they are selling, and will only care about selling something and getting the commission before mounting up and riding off into the sunset before the victim finds out they'd "been 'ad" ?