Air Source Heating

[Octy0GG]

Considering Air Source Heating.

 

Persuade me / dissuade me - whichever.

 

Can't promise to follow your advice but I won't argue with it.

 

Thoughts obviously on air source in general.

 

But also Daikin Alththerma 3 in particular.

 

I'm in the North of Scotland

 

 

 

 

[BJB540]

Will be very interested to follow this topic. It felt like way too much of an initial outlay when we looked into it and having an older, relatively inefficient property too we were dissuaded by family.

[mac11irl]

no experience of it, in fact i havnt even done any reading up on it tbh, but a friend of mine who is big into his domestic efficiency stuff recently sold his house, bought another, and they are currently in a rental as they are (trying to given ecents.. )get work done on the "new" place. its about 25yrs old, extension going on and while at it upgrading the central heating, insulation etc. he was flipping between oil ( no gas main and tank installation distance requirements would have the cylinder in the middle of the back lawn.  ) and air source for weeks. committed to the air source about 10days ago... if he has chosen the heavy upfront. its because he sees the potential in it. house is on the west coast of ireland... ie fairly battered by miserable weather...

[Octy0GG]

11 hours ago, mac11irl said:

no experience of it, in fact i havnt even done any reading up on it tbh, but a friend of mine who is big into his domestic efficiency stuff recently sold his house, bought another, and they are currently in a rental as they are (trying to given ecents.. )get work done on the "new" place. its about 25yrs old, extension going on and while at it upgrading the central heating, insulation etc. he was flipping between oil ( no gas main and tank installation distance requirements would have the cylinder in the middle of the back lawn.  ) and air source for weeks. committed to the air source about 10days ago... if he has chosen the heavy upfront. its because he sees the potential in it. house is on the west coast of ireland... ie fairly battered by miserable weather...

Thanks

 

What you are saying is reminding me of another side issue - Does anyone know how are these systems viewed on the housing market?

 

[PetrolDave]

18 minutes ago, Octy0GG said:

 Does anyone know how are these systems viewed on the housing market?

Anything that is "non-standard" tends to have a negative effect.

[cheezemonkhai]

Have air source heating/cooling, but only air to air.

 

As such it's only partly relevant if you're thinking of heating plus hot water air:water.

In that situation I would go ground source if you can, but if not then air source can be excellent and if you have solar pannels can be cheaper than gas.

 

 

They are primarily used as AC, then used to heat in the months where it's cold but not cold enough to put on the gas heating.

This has extended the number of months the heating is not on for, but also reduced the temperature (21-18) that the stat is set two, because we can heat some spaces with the units in higher if we desire.

The house is boiling in the summer (Dead south facing, plus almost full wall windows and huge solar gain). but tend to set the temperature to 21-23.

 

We don't currently have solar pannels, and 2 * 12,000 BTU AC/Heating units have in for just over 10 months, but in that time they have consumed a total of 57kWh of electric, split as 36kWh cooling and 21 kWh heating.

The interesting bit is that for 10 months of heating and cooling, with the gas boiler turned down, the heat pump useage translates to just £10 in total (for the whole 10 months), so £1 per month to be cooled in the warmer months and the heating topped up in the cooler ones.

 

When the gas boiler dies, I'll be seriously considering ground or air source heat pumps and solar panels with a battery.

Big up front cost, but very low running costs and saves elsewhere.

 

 

 

[cheezemonkhai]

8 hours ago, Octy0GG said:

Thanks

 

What you are saying is reminding me of another side issue - Does anyone know how are these systems viewed on the housing market?

 

 

8 hours ago, PetrolDave said:

Anything that is "non-standard" tends to have a negative effect.

 

I disgree and so did a RICS surveyor, who stated when I was remortgaging that they would be very attractive to buyers.

The house is valued approx 5% higher than an identical one only a few doors down, by the same suryeror and they stated it was the heat pump AC that did it.

 

They also said heat pump heating will be interesting to many buyers as people are very concious of the cost of bills (as well as some green concenrs).

 

[BJB540]

14 minutes ago, cheezemonkhai said:

Big up front cost, but very low running costs and saves elsewhere.

 

 

 

 

Is it realisable in the life span of the units?

[J.R.]

23 hours ago, Octy0GG said:

Considering Air Source Heating.

 

Persuade me / dissuade me - whichever.

 

I'm in the North of Scotland

 

 

Ignoring the loss of efficiency will it actually heat or put out enough heat in your winter conditions?

 

Real heat and not the salespersons hot air.

 

Its probably warmer where I am than you and I could not rely solely on the air source heat pump in winter, it spends more time cycled off & defrosting the evaporator than heating & probably consumes more watts than it gives out as heat energy.

 

 

[cheezemonkhai]

31 minutes ago, BJB540 said:

 

Is it realisable in the life span of the units?

Vs traditional AC definitely.

 

As heating on anything but gas yes, but the gas servicing would probably make that a yes too.

 

Solar/battery is the high cost, but with the lower costs and the fact you save elsewhere on electric and can resell any spare to the grid, I would say it’s worth it. 

 

12 minutes ago, J.R. said:

 

Ignoring the loss of efficiency will it actually heat or put out enough heat in your winter conditions?

 

Real heat and not the salespersons hot air.

 

Its probably warmer where I am than you and I could not rely solely on the air source heat pump in winter, it spends more time cycled off & defrosting the evaporator than heating & probably consumes more watts than it gives out as heat energy.

 

 

 

The house is modern, so well insulated, however the boiler was off for a few days due to a condensate pipe leak. During that time the AC units were in heat mode, the room doors left open and the house was up around 21 degrees. It’s a reasonably big house, so I would think so.

 

The water systems top up with electric if they need more heat, hence the idea of solar.

 

Ground source will obviously give more heat for a given time of year.

[J.R.]

Mine is more than capable of heating my appartement, I use it during spring and autumn where the weather is too changeable for the storage heating, I also use it if I return to the property in winter when it has no been heated during my absence, primarily because the storage heaters wont give out any heat till the next day and I have to heat the fabric of the building.

 

Thats when I know that my system is not up to the task in very cold conditions but it was never intended to do so.

 

How cold was it outside when you used yours as the sole heat source?

 

I suspect the OP in North Scotland gets some very cold weather, the efficiency of the units drop off drastically but as a user I know there is more to it than a theoretical rating, mine will heat albeit inefficiently but if its only putting out that heat 15 minutes per hour while cycling & defrosting (which wastes electricity) the theoretical efficiency of when it does work will not keep you warm.

 

Maybe the modern units are far better, ground source does not have the same limitations.

[john999boy]

This site is quite knowledgable and some assistance will be forthcoming!

[Octy0GG]

Thanks to everyone who has posted. It's all good food for thought

[cheezemonkhai]

1 hour ago, J.R. said:

Mine is more than capable of heating my appartement, I use it during spring and autumn where the weather is too changeable for the storage heating, I also use it if I return to the property in winter when it has no been heated during my absence, primarily because the storage heaters wont give out any heat till the next day and I have to heat the fabric of the building.

 

Thats when I know that my system is not up to the task in very cold conditions but it was never intended to do so.

 

How cold was it outside when you used yours as the sole heat source?

 

I suspect the OP in North Scotland gets some very cold weather, the efficiency of the units drop off drastically but as a user I know there is more to it than a theoretical rating, mine will heat albeit inefficiently but if its only putting out that heat 15 minutes per hour while cycling & defrosting (which wastes electricity) the theoretical efficiency of when it does work will not keep you warm.

 

Maybe the modern units are far better, ground source does not have the same limitations.

cars had ice in the morning and I would say day time temperatures were in the Low to mid single figures.

 

The modern units are definitely much more efficient and capable than those from 5-10 years ago.

 

That plus they spend a lot less time in defrost than the older units.

[cheezemonkhai]

1 hour ago, john999boy said:

This site is quite knowledgable and some assistance will be forthcoming!

Assistance as in grants?

 

Also worth mentioning that Air or ground to water Systems still get renewable heat initiatives payments...

[john999boy]

29 minutes ago, cheezemonkhai said:

Assistance as in grants?

Assistance as in information. 

[meta55b]

From my own personal experience with air source heating, don’t. I have about 300 houses out of about a 1200, that I have to deal with, that were installed with air source and there’s constant callouts for breakdowns and repairs. An engineer once told me that the Daikin are terrible and should have installed the Mitsubishi ones, His word not mine. 

[cheezemonkhai]

18 minutes ago, meta55b said:

From my own personal experience with air source heating, don’t. I have about 300 houses out of about a 1200, that I have to deal with, that were installed with air source and there’s constant callouts for breakdowns and repairs. An engineer once told me that the Daikin are terrible and should have installed the Mitsubishi ones, His word not mine. 

I heard the opposite for air to air.

The Daiken air to air are excellent, few Problems, much quieter than the Mitsubishi and Fujitsu units and far less electrical DC noise to trip breakers.

 

I have heard the earlier altherma air to water were trouble, but I wouldn’t avoid air/ground source heat pumps generally just because of one brand.

[meta55b]

The ones i have dealings with are air to water. Only forwarding the info from what I’m told by the tenants, repair history’s and engineers comments. 

[cheezemonkhai]

Useful info for sure.

 

Sadly just like gas boilers, some are excellent, some are trouble.

The idea is sound, but I would definitely look for ground source if I could fit it.

[robstaaaar]

My penneth worth:

 

I work for a housing provider in london.  We had a scheme where the Ecodan/Mitsubishi ASHP's system was fitted.  The installer didn't fully understand the system and fitted/commissioned many components incorrectly.  That, together with uninformed users, caused no end of defect call outs for maybe 2-3 years, ranging from programmer and room stat issues, to leaks, back flows and cold spots in certain rooms.  It was eventually resolved by another subcontractor IIRC.

 

Generally, the full package itself works well in principle and would be something I'd invest in, together with a PV and battery storage set up.  If you can, select a handful of installers and ask to visit/demo their work from a previous client (obviously, covid allowing).  ASHP's are widely used in many parts of the world, so it's a proven technology.  Also, gas won't be around for much longer...

 

Hope that helps.

 

Robstaaaar

 

 

[Aspman]

We're geting this on our new build. Air to water I believe.

 

We did some research into this and the basics of what I found were this -  on a new build with modern insulation they can work well and be efficient. If you're not in a new or very recent build don't touch them they'll be ruinous.

 

We're also putting in underfloor heating so the pump is only heating the upstairs. Also the temperature of the water produced by the pump is lower than you get from a traditional boiler so to output the same heat your radiators need to be much bigger.

We can reduce out radiators because of the output from the underfloor heating but they will still be very large and we're looking to mount them vertically so we don't lose too much wallspace.

Edited 4 June, 2020 by Aspman

[cheezemonkhai]

I was advised full underfloor meant no radiators at all on that floor.

 

You might want to check as it was very much oversized radiators or underfloor not both.

[VWD]

For anyone in Scotland pondering this ,I'd suggest logging on to Pistonheads and contacting a member "Get Carter", who lives somewhere nar Applecross and has something similar installed in his house.

[Aspman]

18 hours ago, cheezemonkhai said:

I was advised full underfloor meant no radiators at all on that floor.

 

You might want to check as it was very much oversized radiators or underfloor not both.

 

That's right, we'll have no radiators on the ground floor but big uns upstairs.

 

We saw the radiators in the first completed house were there was no underfloor heating. They were insanely huge. We did not want that.