Wet Air Source Heat Pump

Cocksure

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Hi,
Does anyone have a wet air source heat pump and if so what are the electricity cost of running one, how long do they take to heat up the radiators, how hot do they get etc.

Basically I know nothing about them but quite fancy fitting one myself to try. So any information/feedback would be helpful. Currently planning on fitting a 14kw Mitsubishi unit if there any good?

Also does anyone know if you can link two units together into one system? It’s 240 square meters so the 14 kw is probably not large enough to do it all and a second unit might well be required if the 1st one works out. I just plan to do so many radiators for now and the remainder of a old gas boiler as needed
 
I don’t know a massive amount about these but have fitted 2 very large Mitsubishi ones to a school! (HVAC engineer)
This is not something I would recommend fitting yourself, as you will have zero warranty. Even the ones I fitted HAD to be commissioned by the manufacturer for warranty purposes and they are very picky. We also had to get another company in to do lots of flushing and put additives in the system.
Plus glycol had to be added by them and it is pretty expensive.

You could do all the internal work and get a company to supply and fit the outdoor unit plus commission it. In theory they should be able to offer you a good price as they get good discounts and you only have to pay 5% vat to them for home use.
 
What is a wet air source heat pump?. I know about air source heat pumps ..I have a Danfoss AX11 , I know about shallow geothermal.. actually solar wet brine circulation collectors,and I know about deep vertical bore collectors.. but wet air?.
 
What is a wet air source heat pump?. I know about air source heat pumps ..I have a Danfoss AX11 , I know about shallow geothermal...
Know it all :p;)

I meant a air source heat pump that then heats water which then heats your house, instead of the air to air system, meant air to water setup (that’s the term :rolleyes:)
 
I have an air source heat pump to heat my pool in the summer :cool:

Only a small pool but its alot cheaper than an electric heater. The COP is 4.9 which is pretty good for air source.

Underfloor heating is best used for ASHP which requires lower running temps. A well insulated house is also a bonus.
 
I have an air source heat pump to heat my pool in the summer :cool:
Nice :smashin:

Currently looking into building a passive house at the moment so everything is on hold until I know one way or another with that. If I do get permission then it seems like the ideal product to use for the heating especially as I would like to fit solar panels as well (costs depending etc)
 
Not relevant to yourself, but many new builds in Canada use this kind of heating system I believe. But electricity is quite cheaper over in Canada than the UK
 
Hi guys, sorry to jump on the thread but we are having problems with our Nibe air drawn heating.
It was installed when we bought the house 9 years ago brand new, we just cant find anyone who will look at it close to where we live (Bath, SW England) if you have any ideas you can give me I would be grateful.
 
Hi guys, sorry to jump on the thread but we are having problems with our Nibe air drawn heating.
It was installed when we bought the house 9 years ago brand new, we just cant find anyone who will look at it close to where we live (Bath, SW England) if you have any ideas you can give me I would be grateful.
Have you tried contacting Nibe themselves? Likelihood is that they will have a list of improved installer or will offer a repair service themselves
 
[QUOTE Currently looking into building a passive house at the moment so everything is on hold until I know one way or another with that. If I do get permission then it seems like the ideal product to use for the heating especially as I would like to fit solar panels as well (costs depending etc)[/QUOTE]

Look to insulate the crap out of it first and orientation (to the sun) for passive solar gain and use well insultated windows. This is easy to do especially on a new build. Once you do this then look at the heating. The more insulted it is, will mean lower heating required. If it is one of the sealed type houses (which is good), then I think you have to look into air ventalation. When you are looking at heating systems make sure the heating engineer has all the necessary u values of the building envelope so the system is tailored to your house. Too many still use standard figures and no. of bedrooms for heating system sizing. (Solar hot water heating is a good way to heat the water).
 
Did you go ahead with the Mitsubishi ashp? Would be very interested to see how it’s performing.
 
Did you go ahead with the Mitsubishi ashp? Would be very interested to see how it’s performing.
Not yet, the planning permission was turned down for a passive house, so all my energy has been worked out alternative options. It is still something that I do want to fit though when I do finally sort out having somewhere new to live. One thing that comes across strong though is that the insulation of the property needs to be very very good for them to work, I have just made an offer on a grade 2 listed building so figuring out how to do that should be fun!

PS thanks for the video, getting real users feedback is useful :)
 
Not yet, the planning permission was turned down for a passive house, so all my energy has been worked out alternative options. It is still something that I do want to fit though when I do finally sort out having somewhere new to live. One thing that comes across strong though is that the insulation of the property needs to be very very good for them to work, I have just made an offer on a grade 2 listed building so figuring out how to do that should be fun!

PS thanks for the video, getting real users feedback is useful :)
We live in an old house that’s well (not brilliantly) insulated and it definitely does leak heat, but generally in cosy rooms, with closed doors it works a treat.

look forward to hearing your updates if you successfully purchase your new property.
 
Looking at fitting one to my house and the advice from a leading expert in the field is to sort the insulation and draughts. I have managed through improving the insulation (new windows, cavity wall insulation, extra roof insulation (12" plus), draught management (sealing all skirtings etc)) to reduce the heat requirements for the house by 50% and that makes an ASHP a very viable option in my case. Still have to increase the size of some radiators and fit a more efficient hot water cylinder because of the lower primary temperature.

You have to get them professionally fitted with certificates to get the grant which is definitely worth getting.
 
Looking at fitting one to my house and the advice from a leading expert in the field is to sort the insulation and draughts. I have managed through improving the insulation (new windows, cavity wall insulation, extra roof insulation (12" plus), draught management (sealing all skirtings etc)) to reduce the heat requirements for the house by 50% and that makes an ASHP a very viable option in my case. Still have to increase the size of some radiators and fit a more efficient hot water cylinder because of the lower primary temperature.

You have to get them professionally fitted with certificates to get the grant which is definitely worth getting.
Sorry for the delay in responding .. but yes. Insulation and draft exclusion is the cheapest fix.. many decades ago, I went around with a paper mache pulp filling gaps in floorboards and skirting boards ..it doesn't come cheaper than that. Attic insulation with rockwool is a 200 quid once off.
The huge difference with a heatpump is that you run it 24/7 for peak efficiency. This sounds counter intuitive, but it is true. If the smaller radiators ( smaller and less efficient) are continuously pumping lukewarm water at 36degrees they heat the rooms just as well to 21 degrees as a thumping big oil boiler squirting out 70 / 80 degrees water in fits and starts. The huge difference is that the heatpump needs to be outputting at a low temperature otherwise it looses its efficiency.
 

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