Air Source Heat Pumps

Many thanks both. Air to air sounds like it might be worth investigating.

The floor isn't insulated......it is solid, with no foundations.

Interesting to hear about the heat sink. Thatch typically is a good insulator, and we have cold roof insulation as well. The walls are generally two layers of outer stone with general scree in between, rather than solid stone, which may make a difference. I have found that thatched houses seem to take a long time to warm up, and a long time to cool down, but once they are at a temperature they will keep there. Ours was lovely and cool this summer, until about the last week or so of the heatwave. It also stays warm in winter - normally we are the last to see any snow melt from the roof.

Edit: there seem to be quite a few use cases out there on ASHP usage for thatched cottages. Thanks again all.
 
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I know mates in NZ used air to air heat pumps and were always on about installing them ( 1 was a sparky and other a plumber)
1 of them lived in a timber chalet with no insulation overlooking Queenstown, so a fairly cold climate and that and log burner heated whole chalet even in winter.

Never understood why they haven't taken off here as seem relatively easy to retro fit into old houses and actually do work.
They've been using them over there for 20 odd years really.
 
I've heated my house with a warm air pump as we call them in Sweden for the last 6 years. My system only warms the house but its worked flawlessly . The house stays at a costant 21c all winter even when the out side temp is -20.
 
Mine too, although I'm on the Devon moors. I say, if you have decent insulation and UFH, it's they way to go. If you have radiators you need to get them up to a higher temperature than UFH, that's when the ASHP may become unviable. I would suggest getting a reputable firm round to go through the options, then you can make an informed decision. I can give you the name of the firm that did ours but not sure if that's allowed on here.
 
It's odd, my neighbour has one from Samsung I believe it's a big old unit bits it mounted on the side of the house above the garage so you'd never know. They are one or two teething issues but any new equipment does had it for a few years now and it's been fine.
I think installation is key.
Their house is mind 50's when it was built not exactly new.
 
Out of interest & given that a high tech heat pump installation is a considerable investment that will cost 3 , 4 or possibly more times what a standard oil or gas boiler would cost with air to air if you do not use ducting how do you controllably distribute the heat to individual rooms in a normal house with doors that are generally closed & how do you regulate the temperature independantly in those seperate rooms when most people would have bedrooms at a considerably lower temperature than say bathrooms or living rooms?

Air to air does have its place but IMHO that is in extremely well insulated, generally Scandinavian, propertys that generally use ductwork pre installed at the initial build stage to distribute the heat controllably to all rooms, normally via temperature controlled electric dampers fitted to the ductwork, think £££. Just my opinion & installing Air to Air outside of these parameters could be an expensive mistake if you were looking for controllable heating in all rooms similar to your experiences with radiators or UFH.

Once you have made your home 100% draught free & insulated it to within an inch of its life, fully understanding how to use / run an ASHP installation is also a major part of getting it to work efficiently & to its best capabilities. They do not function anywhere near like most peoples understanding of how you can run /operate an Oil or Gas boiler.

Plenty of research before committing would be my advice & if you take the plunge get your chosen installer to give you a cast iron money back heat guarantee on your room temperatures & domestic hot water temperatures. That will sort out the men from the boys!
 
Out of interest & given that a high tech heat pump installation is a considerable investment that will cost 3 , 4 or possibly more times what a standard oil or gas boiler would cost with air to air if you do not use ducting how do you controllably distribute the heat to individual rooms in a normal house with doors that are generally closed & how do you regulate the temperature independantly in those seperate rooms when most people would have bedrooms at a considerably lower temperature than say bathrooms or living rooms?

Air to air does have its place but IMHO that is in extremely well insulated, generally Scandinavian, propertys that generally use ductwork pre installed at the initial build stage to distribute the heat controllably to all rooms, normally via temperature controlled electric dampers fitted to the ductwork, think £££. Just my opinion & installing Air to Air outside of these parameters could be an expensive mistake if you were looking for controllable heating in all rooms similar to your experiences with radiators or UFH.

Once you have made your home 100% draught free & insulated it to within an inch of its life, fully understanding how to use / run an ASHP installation is also a major part of getting it to work efficiently & to its best capabilities. They do not function anywhere near like most peoples understanding of how you can run /operate an Oil or Gas boiler.

Plenty of research before committing would be my advice & if you take the plunge get your chosen installer to give you a cast iron money back heat guarantee on your room temperatures & domestic hot water temperatures. That will sort out the men from the boys!
i am afraid you are wrong there i have installed air to air heat pumps in scandinavia for 25 years i have never used or seen used ducting just keep the doors open and the air flow form a unit installed in the right place will heat the hole house with no problem and it doesn’t have to be a highly insulated house good old houses with a bit of drought is no problem and a air to air heat pump doesn’t cost much more than a boiler and is easy to install the problem is just that there is very little experience with them in the UK but it will slowly come it is not for any reason that the unit i am using more than 1 million has been installed in Scandinavia
 
Hi yes i have been working with heat pumps for around 30 years first in Denmark and the last 6 years in Scotland, i will try to give a few facts about heat pumps. Th are 3 types of heat pumps for domestic use, ground source & air source heat pumps are heating water , ground source heat pumps are expensive and not the most efficient, air source are half the price and more efficient and all developing is focused on air to water heat pumps. so where is it it’s goes wrong the 2 types of heat pumps are designed to make 37 c water for heating and 55 c water for bat/hot water 37 c water doesn’t heat a old house so these heat pumps are only for new houses with underfloor heating and low temp. radiators and up to date insulation, i have seen a few adds where they say working on traditional radiators and they do but with 65 c heating water they are very expensive to run a boiler will be half the price . Then there is air to air witch is a good and very popular solution in scandinavia works in new and old houses very efficient but don’t heat domestic water.
i could go on and on but think this will do for now. i will be happy to answer any technical questions

I had Thorsen install an air to air Panasonic system to my cottage here in Ayrshire. Three years later still running faultlessly and keeps the whole cottage warm if I can't be bothered to light the log burner. Efficiency about 5:1 but new systems are quoting 7:1.
Very pleased with it - but no grants available for air - air.
 
I had Thorsen install an air to air Panasonic system to my cottage here in Ayrshire. Three years later still running faultlessly and keeps the whole cottage warm if I can't be bothered to light the log burner. Efficiency about 5:1 but new systems are quoting 7:1.
Very pleased with it - but no grants available for air - air.
Hi thanks great to hear you are pleased with your heat pump i will pop around next time i am in the area
 
My experience with them is that where there is a large household, with high demand for water, the reservoir can be used up very quickly. This then means your running off the immersion which is costly in electric. If however your a small household with low water demands, they can work very well. I suppose the solution for this might be to over spec for the size of the house.
 
My experience with them is that where there is a large household, with high demand for water, the reservoir can be used up very quickly. This then means your running off the immersion which is costly in electric. If however your a small household with low water demands, they can work very well. I suppose the solution for this might be to over spec for the size of the house.
it is just the matter of getting the right size water tank when designing the system
 
Has anyone got any real term experience of ASHP use, am in need of a new boiler and have been quoted various figures with the help of grants or schemes but it still looks an expensive option with heavy initial investment.
Long term will there be a saving or is it a green environmentally option and you pay through the nose for it?
I have fitted several over the last 10 years, the trick is to size the pump correctly, far too many have been undersized and relied on immersion booster heaters for when the outside temperature drops (sometimes from as high as 7C down!
(systems fitted with undersized ASHPs and booster heaters are almost always a disappointment to the end user in my experience)
some more thoughts
you will most likely have to increase your radiator sizes as they will have been designed and sized with a flow temperature of 75-82C dependent on age, ASHPs for the most part run most efficiently in the 35-45C range (although there are some high temperature ASHPs on the market that maintain their efficiency up into the 60-75C range I have no personal experience of those, most ASHPs can be run at 65C but their COP drops to immersion heater levels so bills go up! )
buffer tank, lots of people will tell you its not needed with modern invertor driven systems, dig a little deeper and most manufacturers will agree that it helps by reducing compressor cycles (and thus lifetime) worth finding room for one.
insulation, the more the better ! the less you lose the less you have to put in!
underfloor heating and ASHPs are a marriage made in heaven, if the budget allows thats the way I would go.
secondary heat sources, a log burner can be a very pleasant and effective way of supplimenting the heating, and gives a back up during power cuts and extreme weather
do they work? hell yes! the Scandinavians have been using them for decades successfully
are they cost efficient? as long as you can get the correct level of RHI and you can get an installer who isnt trying to pull your pants down then yes, servicing costs over their lifetime are minimal compared to oil.
solar panels (PV) well worth considering as the excess sent into the grid during the summer can be used to offset the winter running costs
 
Out of interest & given that a high tech heat pump installation is a considerable investment that will cost 3 , 4 or possibly more times what a standard oil or gas boiler would cost with air to air if you do not use ducting how do you controllably distribute the heat to individual rooms in a normal house with doors that are generally closed & how do you regulate the temperature independantly in those seperate rooms when most people would have bedrooms at a considerably lower temperature than say bathrooms or living rooms?

Air to air does have its place but IMHO that is in extremely well insulated, generally Scandinavian, propertys that generally use ductwork pre installed at the initial build stage to distribute the heat controllably to all rooms, normally via temperature controlled electric dampers fitted to the ductwork, think £££. Just my opinion & installing Air to Air outside of these parameters could be an expensive mistake if you were looking for controllable heating in all rooms similar to your experiences with radiators or UFH.

Once you have made your home 100% draught free & insulated it to within an inch of its life, fully understanding how to use / run an ASHP installation is also a major part of getting it to work efficiently & to its best capabilities. They do not function anywhere near like most peoples understanding of how you can run /operate an Oil or Gas boiler.

Plenty of research before committing would be my advice & if you take the plunge get your chosen installer to give you a cast iron money back heat guarantee on your room temperatures & domestic hot water temperatures. That will sort out the men from the boys!
air to air units use seperate cassette type units in each room, all connected by linesets to an outside unit, each cassette allows temperature and time control for each room, standard AC tech from the year dot!
as to ducting, for a lot of the 60's-80's builders put in warm air systems without a dedicated return duct system, they relied on loose door fit or in the posh houses room air vents to provide a return air route, yes you did need supply ducts, but they were usually hidden in stud walls, ceilings etc, with adjustable registers to control airflow to individual rooms in fact locally a builder put in an estate that relied on pure convection to heat the houses (a terrible system that cost a fortune to run, but did actually heat the houses )
 
air to air units use seperate cassette type units in each room, all connected by linesets to an outside unit, each cassette allows temperature and time control for each room, standard AC tech from the year dot!
as to ducting, for a lot of the 60's-80's builders put in warm air systems without a dedicated return duct system, they relied on loose door fit or in the posh houses room air vents to provide a return air route, yes you did need supply ducts, but they were usually hidden in stud walls, ceilings etc, with adjustable registers to control airflow to individual rooms in fact locally a builder put in an estate that relied on pure convection to heat the houses (a terrible system that cost a fortune to run, but did actually heat the houses )
Your description is a split A/C system using an air to refrigerant heat exchange process located within the external compressor heat pump to provide heating & cooling through the same refigerant lines to the ceiling mounted units in the relevant rooms, which can be seperatly controlled & no need to leave doors open to allow warm air to circulate. This is a completely different system to that being described by Thorsen.
Same technology but used in a completely different way.
 
Your description is a split A/C system using an air to refrigerant heat exchange process located within the external compressor heat pump to provide heating & cooling through the same refigerant lines to the ceiling mounted units in the relevant rooms, which can be seperatly controlled & no need to leave doors open to allow warm air to circulate. This is a completely different system to that being described by Thorsen.
Same technology but used in a completely different way.

No it isn't. That's exactly the type of system Thorsen installs.
 
No it isn't. That's exactly the type of system Thorsen installs.
Really.Then why does Thorsen refer to leaving the doors open in his post above to allow air to circulate around the house, presumably from a fixed unit in one room? No need to do that with the system you have described?
To get an accurate answer you need to post an accurate description!
 
Really.Then why does Thorsen refer to leaving the doors open in his post above to allow air to circulate around the house, presumably from a fixed unit in one room? No need to do that with the system you have described?
To get an accurate answer you need to post an accurate description!

OK Sir. Crack on.
 
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