Help please! We have to make a decision!

mindovermatter

Hi,
It's crunch time - we need to decide on how to heat our house.
We live in a detached stone built house (1890) on Dartmoor currently heated by an ancient LPG boiler linked to a tank. The house has 2 woodburning stoves already and we plan to put another in the side extension. The house is poorly insulated and no improvements are reasonably possible.
We are due to start a large side extension which will mean moving the boiler to another room.
Advice please on choices as my wife and I are going round in circles.
The choices that I see are
1 - stay on LPG but get modern boiler
2 - get an oil boiler and new tank
3 - try air source heating bolted into existing radiators.
4 - other?
I know that there are some incredibly knowledgeable people on this website who might be able to steer us in the right direction.
Many thanks
Mindovermatter

mindovermatter

Just to add, we do have a 4KW PV system so that cold back up the heat pump - my wife, though, is convinced it won't work!

Cardew

To a certain extent your 'lifestyle' will affect your choice - i.e. at home all day or out at work etc.

A poorly insulated house should rule out a heat pump - apart from the the existing radiators situation. The huge cost of installation is yet another problem.

If you want 'conventional' CH, then IMO oil is your best bet.

Other alternatives?

Modern storage heaters on an Economy 7 tariff. Possibly the cheapest for both installation and running costs, but of course storage heating has disadvantages - especially if you both work. Your daytime consumption is also a factor

As you will have 3 wood burners, could the new one be linked into a CH system via a Dunsley Neutralizer? See:

http://www.dunsleyheat.co.uk/linkupsys.htm

Again with your wood burners in mind, have you considered just having simple(and cheap) electrical heaters? These can be extremely flexible - timed and remote control for very little money.

Whilst their running costs are undoubtably high, the interest saved from the capital invested(or borrowed) will go a long way to offset running and servicing costs.

Notwithstanding the above suggestions, in a house large enough to have 3 woodburners, oil CH would seem to be favourite.

mindovermatter

Hi Cardew
Many thanks for the advice - it is a large house especially with the building work about to take place.
I am with you, my gut feeling says to install oil.
We live the type of lifestyle where we don't need the central heating on all the time - just a couple of hours in the morning and in the evening to warm up bedrooms before children go to bed.
I take on board the idea of boosting the system via the new third stove but my only issue with that is that this extra stove will probably only be lit on limited occasions due to the location.
How about fitting a very low immersion into the new HW cylinder so we could harness the PV ? - say 1KW which could be on all day - the PV produces that even on a dull day.
Best wishes
Mindovermatter

[Deleted User]

Both Cardew and your wife are corect but here is my experience [cut from prev posts] with an ASHP. We used to be on bulk LPG...

Mitsubishi EcoDan ASHP running part fancoils and part UFH in a 108 year old detached house, former station, in Scotland with average insulation. We also have a SW 4kWp PV.

House maintained at 20c all year round with 210lt DHW tank. I don't like a house warmer than 20c but sometimes it is turned up if the wife 'feels' cold... Or will fire up the stove with suff off the floor of the woods.

Total house leccy cost over the last year £650ish though with the PV it is looking like it will be much lower still. I suppose if you look at the FIT income our electricity is free with a big surplus. Plus I believe there is still RHI to come...

Basically the ASHP runs during the day so not on E7/E10 and the like so is supplemented by the PV but during the darker months the PV contribution is to small to make any meaningful difference to running costs.

No it's not cheap to install but as we were starting from scratch due to renovations it made sense. So I would say if you are not prepared to go down the road of UFH, fancoils or replace all your rads and piping etc then oil would is likely to be best. Avoid LPG at all costs. There is biomass but personally I could not be bothered with that never mind the hastle of boiler stoves. With being all electric I don't have the hastle of buying from local suppliers who will always jack there prices come winter. If I get a power cut I'll just run the stove hot.

The ASHP has so far presented no issues whatsoever in winter as is rated and designed to work to -25c. Yes the ASHP will produce less heat at these lower temps but we are sized correctly so not an issue. If it gets to -25c then I'll have bigger problems elsewhere...

It suits us as we just 'forget' about heating and electricity bills now.

Cheers

PS I'd be surprised if there were no insulation measures you could take.

Surely the new extention will be well insulated, ours are?
Insulate under floors, seal round skirting, windows, doors etc
Insulate walls, either internally or CWI
Good doors and windows so zero drafts
But always make sure there is controlled ventilation too.

ankspon

All i want to know is do you want a lodger,it sounds great

[Deleted User]

mindovermatter wrote: »

Hi Cardew
Many thanks for the advice - it is a large house especially with the building work about to take place.
I am with you, my gut feeling says to install oil.
We live the type of lifestyle where we don't need the central heating on all the time - just a couple of hours in the morning and in the evening to warm up bedrooms before children go to bed.
I take on board the idea of boosting the system via the new third stove but my only issue with that is that this extra stove will probably only be lit on limited occasions due to the location.
How about fitting a very low immersion into the new HW cylinder so we could harness the PV ? - say 1KW which could be on all day - the PV produces that even on a dull day.
Best wishes
Mindovermatter

There is a lot of chat on many forums about heating DHW with PV.

Would it not be better to just let the PV cover the baseload of the house and consider solar thermal?

Cardew

If you go to the 'Green' forum there are all sorts of 'schemes' to maximise the use of PV generated electricity.

Your 1kW immersion heater has been suggested, as has a standard 3kW heater connected to a 110v transformer often used for builders tools.

Frankly I think these ideas are not worth the trouble, indeed if the PV panels don't cover the heater consumption(dull day and house background consumption - fridges etc) it will actually cost money as you will be using daytime electricity rates to supplement.

Edit.
I would echo Jeep Junkies' point about insulation. Money spent on insulation is a real investment.

grahamc2003

Remember that full house, air to water heatpumps attract subsidies - I think the one-off premium payment is £800, and then there's the rhi which wll comne into force at some stage, which will probably/possibly be around 7/8p/kWh probably/possibly deemed on the heat loss survey (not actual heating).

It will have to be commissioned (effectively meaning installed) by the MCS cartel, so won't be cheap. Also, they're bound to spec new radiators (or possibly more) - not sure if they'll install something other than what they specify and still collect the rhi. (Anyone know?)

The biggest concern, imo, with (decent, i.e. daikin, mitsui) heat pumps is
the correct installation and setup, assuming your house is fit for one.

mindovermatter

Hi Jeepjunkie,

Many thanks - youve just put me in a spin again - talk about me sitting on the fence!
I have asked the air source chap for some references to work that they have done in similar houses.......
My wife now likes Cardew's advice re simple electric heating as we are looking at huge startup costs for the oil which would pay for years of electric panel heaters in bedrooms. We already have electric showers so would not need tankful of hotwater all the time.

pit1821

mindovermatter wrote: »

Just to add, we do have a 4KW PV system so that cold back up the heat pump - my wife, though, is convinced it won't work!

Depends what you want the heater to operate normally in sikoni.