Air source heat pump question.

lindal1000
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Re: Air source heat pump question.

Post by lindal1000 » Sat Feb 23, 2019 4:20 pm

We have Air source heat pump. It's not noisy at all. Wasn't that much more than installing any other kind of heating either. We built a little three sided block work wall to hide it and deflect the noise, but after installing it we said we need not have bothered with the wall.

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Re: Air source heat pump question.

Post by Catrose » Sat Feb 23, 2019 7:04 pm

We have one, and I do find the noise a little annoying on those rare sunny days in winter when we eat outside. In the summer it of course isn't noisy at all. Our main problem is that since we live in a cold area it is much more complicated if we want to go away for periods in winter as can't drop it down to 6degrees as pump might still freeze. And we can't drain it as we have underfloor heating. The pump needs to have hot water circulating around inside it. So we have to leave it at 19/20, and turn the radiators to hors gel so only heating a small amount of water. But it annoys me.

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Annabelle's Papa
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Re: Air source heat pump question.

Post by Annabelle's Papa » Sun Feb 24, 2019 9:32 am

ALBMFFS
OK, I'll take the bait, the below was like cheapest system that the company sold at just under £400, installation, you could double that price.

Depending on what you pay per Kilowatt hour. So for example you pay €0.25 per kilowatt hour and if you want 2.5kw per hour with a standard convector heater it would cost €0.25 x 2.5kw to run per hour so €0.625 but on a thermostat once it had reached the desired temperature it would turn off and then click back on, an ASHP you are getting the bonus of the inverter technology so approx €0.16 per hour (working on a COP of 4) but again, once it had reached the thermostat temperature it would turn off and then click back on again.

https://www.ebay.co.uk/itm/Mitsubishi-A ... 0005.m1851
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Re: Air source heat pump question.

Post by F Flinstone » Sun Feb 24, 2019 1:44 pm

For new builds you now only have three choices for heating, Gas condensing boiler, we would be on a gas tank, so no thanks, wood pellet boiler, if you have the room for a one tonne hopper nice idea, we have the room but we went for the third option of Air/Water Heat pump with UFH. We have gone for a bi-zone model so it will do UFH, or wet rads, we are not worried about them not being so efficient in the winter months as the large volume of water stored in the inside tank has a 3kwt immersion heater fitted to "Top" up if necessary, the cost of the pump and storage cylinder is 8000€ the whole package is 15000€, for retro fitting it would be a lot more expensive.

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Re: Air source heat pump question.

Post by Hal » Tue Mar 05, 2019 12:20 am

Annabelle's Papa wrote:
Sat Feb 23, 2019 9:23 am
We are looking at installing one in our large lounge, we will only want it for heating, never cooling, so where to position the external unit ? My thoughts are on a south facing wall to take advantage of any warmed air from the sun, also why not build an open ended green house around it so it would be protected from frost, snow and ice, my theory is if you can raise the air temperature around it, it would need less electricity and heat the room quicker.

Please feel free to shoot my thoughts down. Or any advice/tips that you might have.
Will this be the only type of heating in the room? I ask because I note where you live as an ashp, whilst efficient, is useless at producing high temperature heat, so it needs to stay on for longer to heat things up which is why their operating cost pans out to be the same as convential heating at the end of the day. I am a thousand kms south of you where I do not need highly heated air, but do notice that it takes quite a bit extra on a really cold evening when it is -3 or so...sometimes even calling for a blast from a small fan heater to start.

Definitely do not cover the pump with anything - leave it to draw air from all around, preferably on a south facing position.

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vic evans
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Re: Air source heat pump question.

Post by vic evans » Tue Mar 05, 2019 7:02 pm

Hal wrote:
Tue Mar 05, 2019 12:20 am


Will this be the only type of heating in the room? I ask because I note where you live as an ashp, whilst efficient, is useless at producing high temperature heat, so it needs to stay on for longer to heat things up which is why their operating cost pans out to be the same as convential heating at the end of the day. I am a thousand kms south of you where I do not need highly heated air, but do notice that it takes quite a bit extra on a really cold evening when it is -3 or so...sometimes even calling for a blast from a small fan heater to start.

Definitely do not cover the pump with anything - leave it to draw air from all around, preferably on a south facing position.
Hal,I post in trepidation of receiving more 'verbal' from a Global administrator of this non Global network for pointing out innacuracies in your post :lol: & whilst not wanting to be the the protector of the weak and unwary :roll: as has been suggested I do feel your post does warrant some response if only to assist those contemplating air- air heat pumps.
"useless at producing high temperature heat,".. Not useless but a function of the design of the things. Modern refridgerants are normaly able to support temperatures in the 50/60 deg C range so expecting anything higher would be futile.
"so it needs to stay on for longer to heat things up "...Heat loss calculations are based on 'steady state conditions' & heating systems are assumed to run 24/7. Any variation to these criteria, such as intermittant heating, require an uplift in both the heat source & heat emmiters dependant on environmental conditions. When I was designing in the SW UK it was normal to assume a lower outside temp. of 0 deg C for example. If your system requires auxiliary heating it could be for either of the the above reasons or simply poor design. To say that " which is why their operating cost pans out to be the same as convential heating at the end of the day. is a statement based on ignorance & does little to help other considering such systems.
I have designed & my company have installed numerous hybrid commercial installations using 'low' temperature hot water around 55 deg C using suitably sized fan convectors with zero problems. Designed correctly, for the environment it will operate in there is absolutely no reason why an air-air heat pump will not function well as long as minimum outside temperatures are considered & running costs using the latest inverter/gas technology can result in running costs other systems will struggle to match.
I'm here to help where I can. The sarcasm & insults are just a complimentary service I provide.

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After the Storm
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Re: Air source heat pump question.

Post by After the Storm » Tue Mar 05, 2019 9:50 pm

;) :P :lol: :innocent: ;)


Hal
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Re: Air source heat pump question.

Post by Hal » Wed Mar 06, 2019 1:05 am

Vic, i think we agree on everything, but you are being kinder to the air pumps in explaining the reasons why..

An air pump IS 'useless' for produing high temperature heat in UK winter conditions - you put it better by saying futile to expect high heat, yes. I have a split level system in France which is great at warming the place when it is cold at 5 degrees outside. I have a divalent system in the UK that only warms the radiators when a day's high temperature is 1 degree where I have to occaisionally bang on the gas back-up to give us that little extra.

I have never measured the cost of running the air pump alone vs traditional gas heating, so my comments come from what is generally written about the costs. I have though noted that on a cold day using the pump alone, as it would be with a lower OAT, it is on for longer and with the price of electricity as it is....

One day I might do a comparitive test, but then it would be futile as we also have an Aga to give background heat...

You do say 'designed correctly'. Yes, if I were to do a new build, with all the modern insulation I see, and that if space were built to house a decent size pump, that its 'lower' temperature product would heat up things a darn sight quicker. But putting pumps into older houses is not always an ideal design, and therefore efficiency will be compromised requiring longer operation and higher cost.

Design/technology will have to get better as I see the Govt are now talking of banning gas in new builds from 2024 (?) or thereabouts, so there will be no more reliance on the luxury of having a hybrid setup unless they will make one with an immersion back up.

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