Air Source Heat Pumps

Harryo

TiredGeek wrote: »

:we have two domestic meters, neither is E7/E10.

Are they completely separate incoming supplies ? If so are they off the same phase?

TiredGeek

Harryo wrote: »

Are they completely separate incoming supplies ? If so are they off the same phase?

Completely seperate supplies, fuses and meters.
Different phases as well which makes wiring the house a nightmare - you have to make sure there's no way you could stick your fingers on live wires from both phases at the same time or you'd get a lethal 415v rather than the a painful 240v

Middy

I live in a 2 bedroom flat with a large landing and internal stairwell with a ESHP and my direct debit is £44 pcm.

My friend lives in a similar sized 2 bedroom property (1970s terrace) which has GCH and her dd is £72pcm for dual fuel

Harryo

TiredGeek wrote: »

Completely seperate supplies, fuses and meters.
Different phases as well which makes wiring the house a nightmare - you have to make sure there's no way you could stick your fingers on live wires from both phases at the same time or you'd get a lethal 415v rather than the a painful 240v

That really should be sorted out. Either an adequate single phase supply or if really necessary, a standard three phase distribution.

TiredGeek

Harryo wrote: »

That really should be sorted out. Either an adequate single phase supply or if really necessary, a standard three phase distribution.

LOL, nice idea
Small problems though: only two wires run down the valley so can't have "proper" 3 phase, and the transformer on a stick in the field could be overloaded with ASHP & electric showers etc if they all happen to be on at once if it was just all coming off one phase.

Apart from the billing confusion there's no problems with our setup, in fact it's a relief to know we have plenty of overhead on each supply so we're not gonna get supply fuses blowing etc.

Thanks for your concern tho

andrewlato

With my Trianco s1200, last months all electric bill came to 200pounds. That includes HP running constantly for 10 days(very cold weather) and rest days running for about 1h with 2h break in between. It was first month with this HP and she used between 75.6-80kwh every 24h when running constantly so here's why bill was so high. On days when ambient temp is above 2deg it will cost just over 3pounds per day to keep the house above 19deg so not too bad. Shame i cant get her power input down to around 2.5kw as shown in Trianco manual...misadvertising or what???
Im on prepayment E7 in NE Lincs, day 12.6p, night 4.73p ,standing charge 1.61pw
3 bed poorly insulated semi, double brick walls, large UPVC windows(fitted by total Cowboys). on 15/2/12 Im finally getting free loft insulation, that should make it 400mm of total loft insulation.Hopefully the house will get warmer.

Bonny2000

I just moved to a house with an eco dan heat pump. Our first bill came in at £220 for 5 weeks over the Christmas period. Our tarif is reasonable at 11p per KWH. We have a large 3 bed semi and the house wasn't even very warm compared to what we have been used to in the past. I was shocked by the bill..... We lived in a new build flat with GSH before. We are thinking of changing the system to a combi boiler as we like instant hot water and higher heating temperatures on demand. Is this easily done?
Could anyone also explain how different temperatures are set for time periods? Is it on the eco dan wall programmer or on a seperate programmer?

richardc1983

I had my multi split LG inverter air con system installed in my new house in May last year. House is a 1930's end of terrace. Consists of a 9.38kw (FM25AH UE1) heating outdoor unit and 2 x 3.9kw (LIBERO range) (lounge & kitchen) & 2 x 2.1kw (LIBERO rang) (bedrooms) indoor wall mount units purposely oversized so the units can be run constantly in low fan speed. The system is used for cooling in the summer and heating in the winter.

The house also has a GCH system fitted radiators and combi boiler etc. Boiler approx 6 years old manufactured by Glow Worm & is 30kw in capacity.

Having done some tests to see which is cheaper this winter by trying to compare similar temperature weeks one week running GCH then one week running the air con system it appears that it is cheaper to run the GCH. The house gets upto temp quicker by using the air con system but as its warm air you dont get that nice radiant affect you get with radiators which seem to provide a more comfortable even heat and being under the windows they keep the room warmer and at a more consistant temp.

I can keep the flow temp of the rads down on the gas boiler to about 50C and the house maintains about 21C downstairs (TRVS open fully) and about 19C upstairs with the TRVs set lower as dont like it hot in bedrooms. With the air con system we have to have a set point of 22/23C in the downstairs rooms to compensate for the cooler areas near windows where the radiators normally stop any cool draughts from the windows. Bedrooms still set at 19C on the controllers the same as with the GCH. I found that with higher flow temps on the boiler to get the rooms upto temp quicker rooms end up feel stuffy even though TRVs are used reaction times are too slow so the rooms overheat when the TRV shuts off. So a lower flow temp means the boiler is just ticking over and the rooms dont tend to overheat but are slower to warm up but sometimes I turn the boiler up to get the house upto temp then reduce it right down. The air con doesnt even struggle on the colder days. Maybe I bump the fan speeds up a bit or start the upstairs units later once downstairs is close to set temp. When only one indoor unit is running there is a limit to what the outdoor unit can ramp down to so its usually best to have all 4 indoors running for max efficiency as the outdoor unit will still ramp down to the lowest setting and room temps are maintained. A multi unit is designed to run multiple units at the same time and not just one unit otherwise it becomes inefficient.

Cost of using air con per week during period (05th Nov - 24th Dec) ranges between £19-£26 (total elec usage for the house). Cost of using GCH per week during period (31st Dec - 4th Feb) is between £12-£19. Even when just using the air con system at temps below 5C outside I was still finding that I had to use the GCH radiator in the bathroom and the bottom of the stairs otherwise those areas were cold. This was costing £6-£8 per week on gas including the hot water rather than just the £4 for hot water. Over the summer gas usage is just for hot water and is approx £2-£3 per week, so about £2-£4 gets added on top if using the boiler to heat two radiators when using the air con system bringing the total to between £6-£8 for the week on gas alone.

On the weeks where GCH only was used my total electric consumption for the week cost between £10 & £13 as we have a tumble dryer also so some weeks this was used more. Its confused me with all the figures so maybe you can make more sense of the details I have profided. I have also attached my readings for the weeks so you can see roughly what I am using on the weeks without air con and with weeks of just using 2 radiators for the GCH. Above in bold are the dates I used air con and GCH so you can see from the attachments costs for those weeks.

Electric


Gas


There is much debate on if Air Con is cheaper to use for heating than GCH. Looking forward to your views. What do you think based on the data I have provided taking into account usage of electricity without the air con and usage of electric with air con etc.

Kind Regards
Richard.

deano72_2

Bonny2000 wrote: »

I just moved to a house with an eco dan heat pump. Our first bill came in at £220 for 5 weeks over the Christmas period. Our tarif is reasonable at 11p per KWH. We have a large 3 bed semi and the house wasn't even very warm compared to what we have been used to in the past. I was shocked by the bill..... We lived in a new build flat with GSH before. We are thinking of changing the system to a combi boiler as we like instant hot water and higher heating temperatures on demand. Is this easily done?
Could anyone also explain how different temperatures are set for time periods? Is it on the eco dan wall programmer or on a seperate programmer?

im not sure what you mean different temps for time periods,are you refering to eco1 & eco2 settings?if so that is done on the mitsi controllor par-w21.
your bill sounds abit steep,what set up have you got,eg uf heating/rads/type of build ect

shortperson

Hi - we are considering ASHP as part of a renovation to our 'new' house. We have a 1960s bungalow that we want to extend and refurbish. It currently has the original Thorn gas boiler, large bore pipes and steel radiators and we are on mains gas. The house does have cavity wall insulation but needs new windows and doors all round and more loft insulation. It has suspended floors which need insulating too. We are considering UFH with an ASHP, and possibly solar PV to feed electricity to it, and solar thermal for top up water heating. We like the idea of renewables and had previously experienced a lot of problems with our old house which had a Glowworm condensing boiler with radiators, so are somewhat put off a 'traditional' wet CH system. The whole heating system will be replaced whatever we do, and I think we will have UFH whether we have an ASHP or a gas boiler, and we would like to get a woodburner - though that would most likely be used at evenings & weekends when we're around more. We'd want a system boiler with a pressurised system if we do go the gas boiler route. We live in Dorset, so milder weather but it still has been pretty cold the last two winters.

I know that an ASHP will cost more to buy and install, but are we completely bonkers to consider it rather than a new gas condensing boiler?