UPDATED: Air Source Heat Pumps/Air Con - Full Info & Guide, is it cheaper to run than mains gas?

paceinternet

The Panasonic is a very nice looking product, but not suitable to provide the heating to whole of your property.
It is rated to work at outside air temperatues of -5 to +24 deg C
The quoted output is at an outside air temperature of 7 degC. Below that, it will be less, but they do not tell you what it can deliver at 0 or -5.
You will not distribute the air around the whole house from one unit.
If you had the one unit in your main living area, and panel heaters in rooms which are used less often, it may be a solution.
You need to consider changing from E7 to a normal day tariff as well if you dump the storage heaters. E7 tariffs charge more for daytime units than std.

There is no magic to how much heat your draughty bungalow needs, Do some simple calculations based on floor area, or get a proper survey done.
To give you an idea, if you have 60 sq m of floor, and poor insulation with exposed walls you could need at least 120 watts per sq m = 7.2 kw.

Edit: richardc1983 has said most of the same whilst I was typing.

richardc1983

Couple of videos for you to watch:

http://www.youtube.com/watch?v=oCehY4KKE74

And heres my setup, just done this for you:

http://www.youtube.com/watch?v=-0g0Y0_tL_E

Bear in mind that the 2.8kws quoted by the manufactures as the duty this is only achieved with fan speed on high. So if you want to watch tv and have the fan speed on low you will lose capacity. This is why it is better to oversize as for example 3.5kws unit is quoted at high fan speed, you may only require 1.5kws of heat for that room so you can run it at low fan speed and you will have your duty but without the noise of the fan!

hebridean

I'm hoping to start building a traditional 1 3/4 story 200m2 house in the next two months and intend using an ASHP. It will have underfloor heating and Kingspan insulation lowering the u value by 30%.

I've been doing a lot of surfing on the matter and have been taken with the Nibe Fighter and the Sanyo CO2 with the Sanyo being about £3000 cheaper and capable of heating the water to 65c without using an immersion heater. I have also read good things about the Mitsubushi Ecodan and bad things about the Gledhill tank they have been sold with. Though i beleive that they are now being sold with a Kingspan tank. The Ecodan is also cheaper than the Sanyo, but what tank to mate it with that will provide hot water and heating?

Trying to find any impartial info on the performance of the manufactureres units is very difficult as there appears to be very little info out there. Also there seems to be only a handfull of traders selling the pumps online displaying prices. It reminds me of the underfloor heating industry over ten years ago and now you can buy almost everything from Screwfix.

I would be grateful for any info that could help me make up my mind as i'm very confused at the moment.

Many thanks.

Andy_WSM

Andy_WSM wrote: »

Hey guys, I'll let you know if I run into problems - I have nothing to gain or lose here, if it needs moving, so be it and I'll be the first to moan about it and let you know but at the moment it is working perfectly whether the temps be sub zero or double figures. This is new technology to us all, so someone needs to be a guinea pig! I've only done what the manufacturer said you can do - and it does what it says on the tin at the moment...

This morning the loft is actually 0.5C colder than the outside temps, but that's not enough to make me worry again!

Current temps: Outdoor 8.5C, Loft 8.0C, House, usual 22C.

I did notice that the unit ran a lot less last night as it was mild out and the overall power consumption / cost for the past 24 hours is: 12KW/h = £1.35 (11p/kwh)

Going to quote my own post as I got up into the loft on the weekend to see that everything is as it should be and give the unit a clean up.

Well, the good news - it just wasn't dirty! I took Henry into the loft, but there is hardly any dust on the unit and didn't bother cleaning it. It's clean, so best left alone.

I found a slight leak on one of the water connections - more of a weep than a leak, so just tightened the flexi hose and all seems good.

Running costs are still exceptionally low. The timer is set to run for 4 hours in the morning and 8 hours in the afternoon/evening. I'll admit there have even been evenings in the Summer (and some mornings) when I have switched the radiator on in the living room!

Winter is on the way, so I will be watching closely the performance of the ASHP over the Autumn into the Winter, but have got that I just trust it to come on & off as it pleases and do it's thing.

Cardew

hebridean wrote: »

I'm hoping to start building a traditional 1 3/4 story 200m2 house in the next two months and intend using an ASHP. It will have underfloor heating and Kingspan insulation lowering the u value by 30%.

I've been doing a lot of surfing on the matter and have been taken with the Nibe Fighter and the Sanyo CO2 with the Sanyo being about £3000 cheaper and capable of heating the water to 65c without using an immersion heater. I have also read good things about the Mitsubushi Ecodan and bad things about the Gledhill tank they have been sold with. Though i beleive that they are now being sold with a Kingspan tank. The Ecodan is also cheaper than the Sanyo, but what tank to mate it with that will provide hot water and heating?

Trying to find any impartial info on the performance of the manufactureres units is very difficult as there appears to be very little info out there. Also there seems to be only a handfull of traders selling the pumps online displaying prices. It reminds me of the underfloor heating industry over ten years ago and now you can buy almost everything from Screwfix.

I would be grateful for any info that could help me make up my mind as i'm very confused at the moment.

Many thanks.

Had a quick glance at the SANYO CO2 and it makes a big play of getting the domestic Hot Water(for taps etc) to 65C but doesn't say what the CH water temp will be???? admittedly with your new installation with underfloor heating that won't be an issue.

It also(unless I missed it) doesn't give in detail of the COP at various outside ambient temperatures.

There surely must be a 'downside' in enabling it to produce water at 65C??
Could that be in the form of a lower COP?

As I understand heat pumps, they are at their most efficient when raising large quantities of water a few degrees, and the efficiency drops off the higher you raise water temperature. Which is why ASHPs are so suited to swimming pool heating where thousands of gallons are raised a few degrees.

albyota

Hebridean, ASHP is the way to go, but spend more money on insulation and good quality double or even tripple glazing then any of the better quality makes will surfice, IMO Ecodan or Sanyo or Daikin would be your best choice, the
kingspan cylinder is very good, I have seen it in action, a great combination from the professionals, sanyo uses a two stage compresser to superheat the water, call up sanyo and ask for a demonstration, although you would probably have to go to their HQ, don't listen to rumours from those who have not seen or tried, they always seem to focus on the negative side. My system is Ecodan and has performed very well indeed since fitted Oct 08.

hebridean

Many thanks to you all for your replies. I'm now realise that i was not far off the mark in the shortlist of pumps i was considering.

It's my intention to run the pump on an economy 10 tarrif with the tap water heating being done during the early hours and thought that the higher i could get the water temperature at a cheaper rate the better.

Maybe not though.

Cheers.

muckybutt

Thought id add my two penneth, we have just had a Heatking 9000i ASHP installed by way of a council grant and im well impressed, complete strip out of the old oil system and all the old pipework.
Unit 2Kw input 9Kw output, Kingspan cylinder for hw.
It is so quiet it didnt even wake us up this morning like the old thing used to, and weve copious amounts of hot water on tap now, our house is dated back to 1850, mid terrace cottage only single glazed tho due to being listed so im looking at fitting secondary glazing now. With the heating on i was looking at the meter and it goes slower than when the immersion used to be on, also installed is a back up / top up heater when outside temp falls below 2 deg to assist system, all fully pressurised so mains pressure hot water as well.
I would certainly recommend this to anyone thinking of putting ASHP in wether in an old house or a new one.
http://www.heatking.co.uk/bwarmi.html

samtheman1k

We warned though that most modern heat pumps are modulating, which means that during the warm months, they barely have to work to generate hot water, hence the low noise. As the temperature plumets towards freezing, it will be running on full blast and will be a bit noisier!

orkneyviking

Has anyone tried to / or got any advice on some kind of shield to protect the outside unit from the worst of the elements and extend its lifespan?

I have some kind of behive box in mind?


Thanks