Air Source Heat Pumps

matelodave

As said above, get several quotes, but also do a lot of research yourself so you can understand how they work and how to use them - they are significantly different to conventional heating systems and need to be operated differently.

You can do some of your own calculations to work out heat losses. Some heatpump companies like Daikin have calculators on their websites to help you do that. They also have configurators and calculators which can help you work out the costs.

If you've got some idea yourself then you can ask the right questions and better evaluate the quotations. Make sure the companies you ask for quotes are MCS registered

Silent_Dancer

karter wrote: »

I have just had a system installed but I am not happy with the kit provided as it is not the equipment that was discussed at the time of sale. I was quoted on a CTC system that included an intelligent thermal store as well as CTC ASHP.

The have installed 2 eco warrior heat pumps 12Kw & 9Kw. This has the 2 outside units plus 2 indoor inverters. The tank that has been installed is a Powerflow 210 litre tank that has no expansion options for heating a pool or wood pellet heating.

They have also replace 15 of my radiators but to be honest it looks like most of them are the same size as the ones taken out. There are a few that are bigger but not many. the construction of the new radiators looks identical to the ones replaced. The single vane radiators that have been replaced with double vane ones I am fine with.

I have only paid £5300 of the quoted price of £19300
My suspicion is they have installed cheaper inferior products to maximise profit and I am dreading the electricity bills that I presume I am going to be hit with.
They have also promised savings and RHI payments from the govt totalling £50k over 7 years based on the lowest payout figure. They have also confirmed that payments will be backdated to the date of my installation.

Any advice on how to deal with this would be greatly appreciated.

Its a good job you've not payed the balance.

1) They quoted for Swedish CTC heat pumps but installed Eko Warrier units which are probably Chinese.

2) £19K is way other the top for what you've had done, I'd have said no more than £8K is the value of the work.

3) The installer needs to MCS accredited to claim RHI.

4) An Energy Performance Certificate needs to be performed. Was any insulation added to the property? If not you may find that you are ineligible for RHI.

Silent_Dancer

Alfiethefish wrote: »

I have just obtained a quote for fitting an Ecodan W85VHA2 8.5 KW Air to Water heat pump. The property is a 4 bedroomed 18 year old end of terrace home with LPG radiator heating, double glazed to current standard with 100 mill insulated loft ( will put another 200 mill in to meet current standards ) and with PV installation for electric and hot water supplied of thermal roof panels. We have a concrete first floor and solid walls throughout the property.
Our current LPG bill is around £ 2400 a year and Electric is £ 480 a year less the £ 150 a year we get back from selling excess to the grid. So assume £ 2700 for total energy. I am told the cost of running the Ecodan will be £1000 per annum so we shud see a total saving of around £1200 to £ 1400 a year worst / best case.

Installation cost of £8000 against a new LPG boiler quoted at £ 3 K so £ 5 K difference on installation to make up. So my calculation is 5 years to recoup at worst and maybe 3.5 years at best and that is without the £ 1300.00 grant I am told can probably be obtained. I am wondering if this is too simplistic to be correct? We can not have gas as the National Trust is holding everyone here to ransom with a strip of land they want us to pay fortunes for to run gas into the site. Any views.

£3K is steep for a new LPG boiler if the replacement is straightforward. Shop around you should be able to get below £2K.

An alternative would be to look at oil. Guess £2.5K for boiler install and £1K for a tank. Oil is half the price per kWh than LPG so you'll quickly recoup the additional expense.

With an ASHP to minimise heat loss you need to top up your loft insulation and insulate the exterior walls. You will also need to install bigger radiators or underfloor heating. Was this included in the quote?

8.5kW sounds undersized for the property. I'd guess the heat loss at -3°C (which is how boilers are sized) would be 10 to 15kW depending on insulation. With a heat pump the sizing is critical undersize it and your bills will be very expensive as it the heat will be provided by a back up immersion. See heat pump sizing for more info.

Swainyjo

Samtheman1k
As it is a few years on from your original post I wondered if you wouldn't mind letting us know your updated thoughts on the system. ( you must have coped with a bit of coldness by now! )
I ask because we are currently renovating an old barn in France, we have underfloor heating installed and will eventually have rads upstairs. We asked a heating engineer to take a look with the idea of looking at a wood boiler. He, however, favours an ashp and is currently putting together a quote for a system. Having now done a little research into them ( I have to cycle to steal wifi to get online! ) I am really conflicted. I see why he is suggesting one ( given the ufh) and I know they are used quite widely out here( cheaper electricity I believe and they were giving grants! ) but people who hate them really seem to hate them, often without any first hand experience- which you have! I believe they have become quieter and now can cope with lower temperatures. It can get cold here in winter apparently (nievre) this will be our first! But the VERY cold temperatures don't last very long ( I hope). The man is local. One hopes he wouldn't DREAM of installing a system that couldn't cope with the environment it's designed for !!!
We are currently insulating all the roof, draft proofing and have new double glazing. We have VERY solid walls wich are very thick but it is, afterall a barn.
Look forward to yours, or anyone else's thoughts.

[Deleted User]

Looking forward to reading the replies

I written loads on here about mine, in an ancient pile, over the years.

Cheers

Cardew

Swainyjo wrote: »

Samtheman1k

I ask because we are currently renovating an old barn in France, we have underfloor heating installed and will eventually have rads upstairs.
Look forward to yours, or anyone else's thoughts.

There are loads of posts about the performance for ASHPs

One indisputable fact is that ASHPs need to run long hours(even 24/7) to be fully effective.

I would have thought that the hugely complicated French electricity tariffs will need to be taken into consideration. See:

http://www.thisfrenchlife.com/thisfrenchlife/2004/11/electricity_tar.html

Option Tempo
This is the by far the most complicated charging system that you can imagine for electricity, well, after seeing my tax forms
maybe not. This system has six rates of electricity pricing in total. Each day of the year is colour coded, depending on the forecast of usage by EDF for that day.

There are three colours, blue (jours bleus), white (jours blancs) and red (jours rouges) which represent low rate, medium rate and high rate.

On top of this each day has a cheaper and higher rate based on the Heures Creuses option above, with 10pm until 6am being a cheaper rate (heures creuses) than the rest of the day (heures pleines). The rules for tempo are

* The tempo year starts on 1st September.
* The tempo day starts at 6am.
* There are 300 blue days, 43 white days and 22 red days per tempo year.
* The number of days of each colour is fixed each tempo year.
*
Sunday is always a blue day.
* Red days can not fall on a holiday, weekend or more than 5 weekdays in a row.

The good news is that this means, despite the increased standing charge, electricity on blue days is by far the cheapest that you can get it, and during
the cheap rate on a blue day the rate is extremely low.

On white days the rate is higher than either option HC or Base, but not by much. The bad news is that on red days the cost is over 10 times that of cheap rate blue, i.e. it is prohibitively expensive to encourage lower usage.

Of course these days are usually the coldest of the winter.

The main draw back is that you don’t know what colour the next day is until 8pm the night before.

If you can understand that lot, I think it would be essential to have a large thermal store to take advantage of the cheaper rates.

[Deleted User]

Cardew wrote: »

One indisputable fact is that ASHPs need to run long hours(even 24/7) to be fully effective.

Yeah, about 8 hours a day with a foot of snow on the ground outside... Is that much different from GCH?

Cheers

zeupater

jeepjunkie wrote: »

Yeah, about 8 hours a day with a foot of snow on the ground outside... Is that much different from GCH?

Cheers

... probably .... in 8 hours our gas boiler could push out ~250kWh of heating at full tilt (if the radiators could take it !), but in reality, once up to temperature it modulates to suit requirements ... that would result in a serious reduction in the time to reach a decent deltaT operating temperature (~50C+) which is likely double that of the heatpump.

This doesn't mean that the heatpump isn't as good, it just means that it would need to have a different operating/usage pattern. For example, many with GCH would often use the heating for around 1 to 2 hours in the evening (Spring/Autumn) just to 'take the chill off' very quickly when necessary, whereas operating a heatpump to achieve the same effect would result in additional hours of discomfort before the temperature reached the same levels.

HTH
Z

[Deleted User]

So if I understand you correctly.

If both a ASHP and GCH are both timed for 8 hours the ASHP trickles out the heat whereas the GCH goes full tilt then modulates down so the net result is pretty much the same?

Cheers

Cardew

jeepjunkie wrote: »

So if I understand you correctly.

If both a ASHP and GCH are both timed for 8 hours the ASHP trickles out the heat whereas the GCH goes full tilt then modulates down so the net result is pretty much the same?

Cheers

You missed your vocation jeepjunkie, you should have been a politician(or heat pump salesman);)



The point, as I am sure you are aware, is that you can put on the gas CH, say, 20 minutes before you get up or return from work and the house is warm. That isn't the way you can operate a heat pump.

Anyway the point being made to the ex-pat in France is that a large thermal store would enable a heat pump to run during the cheaper periods and avoid the expensive periods.