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

BulliJudd4

I'm going to go ahead with installation of an ASHP to replace the current setup of ancient storage heaters. I'm currently on a Total Heating Total Control (i.e. same as Economy 7) arrangement, whereby there are two supplies to the property (one the off-peak supply to the heating, the other the standard supply - there's a meter for each).

Can someone please explain the implications of this installation on the supply and meters?

Will I continue needing two supplies (one for the new system, the other for the standard electricity supply?) Or will it all go through one meter? I assume the installer will explain and carry out all the associated work, but I'd like to understand it in advance. It'll also be good to be fully equipped with knowledge when I contact my supplier to explain what's happening and change tariff accordingly (or ditch them for someone else!) 

Thanks

sleuth77

Has any of the posters on this particular forum replaced an ASHP with a more energy efficient model and was able to claim the RHI incentives.My Inherited ASHP is 12 yrs old and I’ve had numerous issues with it,I’m thinking of biting the bullet and starting afresh.Many thanks in advance.

matelodave

BulliJudd4 said:

I'm going to go ahead with installation of an ASHP to replace the current setup of ancient storage heaters. I'm currently on a Total Heating Total Control (i.e. same as Economy 7) arrangement, whereby there are two supplies to the property (one the off-peak supply to the heating, the other the standard supply - there's a meter for each).

Can someone please explain the implications of this installation on the supply and meters?

Will I continue needing two supplies (one for the new system, the other for the standard electricity supply?) Or will it all go through one meter? I assume the installer will explain and carry out all the associated work, but I'd like to understand it in advance. It'll also be good to be fully equipped with knowledge when I contact my supplier to explain what's happening and change tariff accordingly (or ditch them for someone else!) 

Thanks

A lot depends on how you'll be using the system and other stuff in the house.  I find that as our unit runs virtually 24hrs/day (not all the time but under the control of thermostats etc) and we set back the night temps by 2-3 degrees then we use most of our energy during the day and evenings and very little overnight (unless it's everso cold). Based on that I've got the cheapest  single rate tariff that I can get - 11.5p/kwh.

The unit uses very little energy during the summer months - about 2kwh a day to produce our hot water but it can look a bit hairy on a very cold day in Jan or Feb when it's heating all day we've managed to use 50-60kwh in a day.  Our total electricity consumption in an average years is around 7000kwh and about half (3500kwh) is used for heating/hotwater and the other half for everything else. So you need to see how you'll be using it all to evaluate whether a multirate tariff would suit you.
Bear in mind that you dont use an ASHP like a normal boiler - they are much more economical when running with low flow temperatures and aren't really suited to on-off, morning & evening  blats like a boiler. Running it longer with lower temperatures is much better so you'll need larger radiators than usual. Be careful that the system is designed to avoid using the boost/back-up heater. The ideal flow temp is around 40 degrees and most heatpumps won't go above 50-55 degrees without using the back-up heater. 
We have a flow between 30-40 degrees (with underfloor heating) and our hot water temperature is set to 45 degrees, with a short boost once a week to 60 to sterilise against Legionnaires Disease

matelodave

sleuth77 said:

Has any of the posters on this particular forum replaced an ASHP with a more energy efficient model and was able to claim the RHI incentives.My Inherited ASHP is 12 yrs old and I’ve had numerous issues with it,I’m thinking of biting the bullet and starting afresh.Many thanks in advance.

I think you'll have to look very carefully at the OFGEM site to check the rules on RHI to see if they do cover replacement installations. I'm guessing that if yours is not registered for RHI you could probably qualify as a new installation, but it may be more complex if it's already registered or you or the previous owner got a grant for the initial installation or RHI payments.

RHI for ASHP only started in April 2014, we had ours installed in 2010 but didn't get a grant and so were eligible for RHI. Some earlier installations could claim a grant but then weren't able to claim RHI.

IMO it is more complicated than it really needs to be, so you need to check the rules very carefully ( I still have to submit a declaration every year to continue receiving  my RH!

sleuth77

sleuth77 said:

Has any of the posters on this particular forum replaced an ASHP with a more energy efficient model and was able to claim the RHI incentives.My Inherited ASHP is 12 yrs old and I’ve had numerous issues with it,I’m thinking of biting the bullet and starting afresh.Many thanks in advance.

I think you'll have to look very carefully at the OFGEM site to check the rules on RHI to see if they do cover replacement installations. I'm guessing that if yours is not registered for RHI you could probably qualify as a new installation, but it may be more complex if it's already registered or you or the previous owner got a grant for the initial installation or RHI payments.

RHI for ASHP only started in April 2014, we had ours installed in 2010 but didn't get a grant and so were eligible for RHI. Some earlier installations could claim a grant but then weren't able to claim RHI.

IMO it is more complicated than it really needs to be, so you need to check the rules very carefully ( I still have to submit a declaration every year to continue receiving  my RH!

Thanks for the reply matelodave.I did email ofgem with various questions but as of yet no reply I will wait till things calm down and try ringing them hopefully I’ll get some kind of incentive.Sleuth

arty688

sleuth77 said:

sleuth77 said:

Has any of the posters on this particular forum replaced an ASHP with a more energy efficient model and was able to claim the RHI incentives.My Inherited ASHP is 12 yrs old and I’ve had numerous issues with it,I’m thinking of biting the bullet and starting afresh.Many thanks in advance.

I think you'll have to look very carefully at the OFGEM site to check the rules on RHI to see if they do cover replacement installations. I'm guessing that if yours is not registered for RHI you could probably qualify as a new installation, but it may be more complex if it's already registered or you or the previous owner got a grant for the initial installation or RHI payments.

RHI for ASHP only started in April 2014, we had ours installed in 2010 but didn't get a grant and so were eligible for RHI. Some earlier installations could claim a grant but then weren't able to claim RHI.

IMO it is more complicated than it really needs to be, so you need to check the rules very carefully ( I still have to submit a declaration every year to continue receiving  my RH!

Thanks for the reply matelodave.I did email ofgem with various questions but as of yet no reply I will wait till things calm down and try ringing them hopefully I’ll get some kind of incentive.Sleuth

Hello,
I'm in the same situation , did you hear back from OFGEM ? I thought if you have or the previous owner has claimed anything for the heat pump then I don't think you are eligible .

sleuth77

Hi arty
No and did ring OFGEM and was promised a reply but sadly nothing yet.Although one of the companies I had in to get a quote said as the heat pump was installed before RHI the previous owner might have got a grant and this would be deducted from any RHI payments,if this helps.
Regards Sleuth

danrv

Have had a read through the article on various ASHP systems. I need to install new heating in my 3 bed semi detached property (electric warm air system). 
Options are down to Quantum storage heaters, ASHP 
wet system or ASHP air to air multi split.

New storage heaters would need E7 wiring installed. Hot water immersion would be timed for cheap rate.
ASHP + radiators would be the most expensive to fit.
ASHP air to air cheaper to fit and heating would be 
more direct and controllable.
Hot water immersion on competitive normal rate electricity.

Just wondering with air to air ASHP multi split, how many indoor units can run from one outdoor? 
Wouldn’t want too many of these on the house exterior.

richardc1983

Just seen the below article, there is a target of 600,000 heat pump installations by 2028! Whilst I am all for supporting heat pumps as the main source of heat, until they bring down the cost of electricity per kWh it is not worth the investment and extra running costs over mains gas. Gas is very cheap so if you have a high efficiency condensing boiler running on mains gas then you are better off with that for your heat than going for a heat pump.

A heat pump produces heat more efficiently and cleanly but the electricity costs more to do so: If we consider my own energy tariff that is a current fixed rate deal 1kWh of electricity costs 13p and the equivalent in gas is just over 2p. If we for argument's sake say that a heat pump is 300% efficient meaning for 1kw of energy used (13p) we are getting 3kw heat from it. On my tariff, for it to break even the heat pump system needs to be about 700% efficient.

A modern condensing gas boiler maybe 98% efficient meaning 3kw of heat generated by mains gas is costing about 7p a heat pump is double. Even the standing charge for gas is considerably less at 9p than electricity which is nearly 3 times as much at 23p.

Homeowners being sold heat pump systems over a new modern condensing boiler are being missold if they have mains gas. The number of people I have come across who have ripped out a condensing boiler and put one of these systems only for operating costs to go through the roof only to rip it all back out and start again is crazy.

If you are on mains gas and looking to replace an older gas boiler, fit a new gas condensing boiler, if you don't have mains gas and are using oil or electrical resistive heating (fan heaters, convectors etc) then fit some form of heat pump. Electrical resistive heating is 100% efficient. Meaning that you get 1kWh of heat out for every 1kWh you use, in my tariff example above that is 13p, so a 3kw fan heater will cost you 39p an hour to run whereas a heat pump will produce 3kw of heat for that hour using 1kw of electricity and cost 13p to do so. The equivalent 3kWh from mains gas is approx 7p.

https://www.acrjournal.uk/heat-pumps/uk-targets-600-000-heat-pump-installations-a-year-by-2028/

richardc1983

danrv said:

Have had a read through the article on various ASHP systems. I need to install new heating in my 3 bed semi detached property (electric warm air system). 
Options are down to Quantum storage heaters, ASHP 
wet system or ASHP air to air multi split.

New storage heaters would need E7 wiring installed. Hot water immersion would be timed for cheap rate.
ASHP + radiators would be the most expensive to fit.
ASHP air to air cheaper to fit and heating would be 
more direct and controllable.
Hot water immersion on competitive normal rate electricity.

Just wondering with air to air ASHP multi split, how many indoor units can run from one outdoor? 
Wouldn’t want too many of these on the house exterior.

See my article above, do you have mains gas this should be the only question you need to ask. If you have mains gas go with a condensing boiler. If you don't and electricity is your only option then go with an air to air heat pump system as you say this will give you the most control. A multi-split system you can have as many as 6 indoor room units connected to 1 outdoor unit so it leaves the outside looking neat and tidy. Look at the LG systems which are a good all-rounder in value and function.