Getting rid of oil central heating - domestic hot water

[Caecilia]

We want to remove the oil boiler/radiators central heating from our 1960s bungalow and install electric underfloor heating. The hot tank is the usual indirect system fed from the cold tank in the loft, water is heated by the boiler with an immersion heater as back-up. The pipework in the loft and running around the house is a nightmare tangle that we're struggling to understand. While we're going to get a professional to do the work, we'd like to understand in more detail how the system actually works. We also want to economise on costs by removing the radiators and as much of the pipework as we can, ourselves, which will also enable us to take up the floor boards and insulate underneath. An important factor to be considered is that one person in this house needs daily hot baths, so we want to keep a hot water storage tank. Other hot water requirements (shower, washing machine, dishwasher) heat water as required.

The cold water storage tank also needs replacing; we have the replacement but have changed our minds about doing it ourselves!

The main questions are:

1. We assume we won't need the feed and expansion tank in the loft as it only serves the central heating? Is this right? The hot water tank will vent into the new cold water tank - currently it's an open vent pipe over the cold tank.

2. Can we keep the existing hot water tank, which is relatively new, and just remove and seal the boiler pipework, or will a new tank be necessary?

3. Is there a system where we can move the hot water tank into the loft, and put it alongside the cold tank? Another thing to be considered is that we might want to put two bedrooms and a shower room in the loft - the space up there is adequate.

3. Thinking longer term, funds might be available in the future to install PV or solar hot water panels on the roof. What should we be thinking about in making our decisions now, so we don't spend money unnecessarily now if we decide to go down this route in the future?

We really need to get this sorted before we go any further with updating the house; it needs rewiring - the old wiring is another maze running over the loft floor; and loft insulation and boarding put down so we have to remove this pipework before we can do that.

We'd really appreciate any advice and suggestions, please, so we know a bit more of what we're talking about when we get the pro's in! Thanks in advance

 

[simond]

You will learn far more in the space of a few minutes with an on-site professional than in 20 emails on a web site.

I am intrigued by your interest in electric UFH when oil fired water UFH would be more responsive and cheaper to run. Since nearly all the UK's electricity is generated using fossil fuels and the typical process from generator to power point is 30% efficient, you will be ruining the planet and your bank balance.

The solar thing does not tally with your proposed squandering of energy resources on the electrical UFH, other than both routes are expensive and pointless.

One can get very confused looking at the wide range of opinions on the net; the old method of getting a site visit and investing your time and money with someone you can trust takes a lot of beating.

 

[Kes]

Simond's advice is good, but to help you get a general grasp of the theory:

1) In the roof there should be a large header tank feeding the h/w system, and a smaller expansion tank feeding the c/h. You (your plumber) can get rid of the c/h expansion tank and its pipework when the wet c/h system goes.

The h/w tank has a separate expansion pipe over it from the top of the h/w cylinder. This stays.

2) I think you mean the h/w cylinder. Yes, this can stay and the boiler connections be plugged.

3) Yes, the h/w cylinder can be put in the roof, but it is not common. You will need enough height for the base of the feed tank to be around 1 mtr above the top of the h/w cylinder just to get some flow out of your taps. Apart from the obvious support for the feed tank you may need to strengthen the base to take the weight of the h/w cylinder. A shower in the roof space is possible, but you will probably need a pumped supply due to lack of height of the feed tank.

3 and a bit) Don't really know, possibly to install a h/w cylinder that is designed to take a feed from solar panels.

Rgds. (18 emails to go)

 

[JohnD]

We want to remove the oil boiler/radiators central heating from our 1960s bungalow and install electric underfloor heating.

you must have money to burn

 

[wilhelm]

get a nice Grant Vortex condensing boiler. They really are quite good.

16 to go.

 

[Caecilia]

Thanks for the responses! Very helpful. I hope there's more to come

The reasons for getting rid of oil:

The tank is ruptured so several hundred pounds would need to be thrown at that straightaway. We were told the 12-year old Worcester Danesmoor boiler wasn't suitable to fire a water UFH system so that would probably be an added cost; we could go back and revisit that. Price of oil v. electricity: who can tell? We can't produce figures to compare but friends of ours can, and with the insulation they have, which we plan to copy, electric UFH is competitive with oil. And who knows what's going to happen to oil prices - light crude at $96/barrel this week and who knows who that madman in Washington's going to bomb next. We hate the noise of the boiler, it drives us up the wall. UFH is quiet; it suits our lifestyle, we don't have a need for quickstart heating to get a family out to work and school in the morning, and we prefer dressing a bit warmer to turning the thermostat up. We also have a strong objection to supporting nasty middle-eastern oil dictatorships if we can avoid it. And aren't we past peak oil anyway?

Appreciate the comments so far - thank you!

 

[Caecilia]

Er... can some kind person advise how we can find an independent consultant to advise on heating, ventilation and insulation, please? We're willing to pay for genuinely independent advice, from someone with no vested interested in selling particular types of products. I've Googled on several search terms but not turned up what I want, maybe I'm using the wrong search words.

Thanks!

 

[gas4you]

Thought about a ground source heat pump? For every unit of electric they use you get about 4.5 x that in heat output.

 

[Balenza]

Caecilia wrote

The tank is ruptured so several hundred pounds would need to be thrown at that straightaway

About £300 for a single skin.

We were told the 12-year old Worcester Danesmoor boiler wasn't suitable to fire a water UFH system so that would probably be an added cost;

The boiler is fine. You need mixing controls though to lower the temperature down to a suitable temperature for the hydronic underfloor heating.

Price of oil v. electricity: who can tell?

Oil is £0.37/L in my neck of the woods. I've never considered electric nor am I likely to.
It may be viable and super efficient on a super insulated new build but then so would oil.

electric UFH is competitive with oil.

If using resistance heaters I doubt it very much.
With a heat pump then mebbe.

We can't produce figures to compare but friends of ours can

OK ,so they have a well insulated home heated presumably by resistance heaters of some kind and it looks efficient.
However I would bet the same home heated with oil would be just as efficient if not more so and I doubt if they can give figures for that unless they have a dual set up installed and accurate heat meters hooked up to a data logger giving a comparison between the two.

We hate the noise of the boiler, it drives us up the wall

You get used to it.

And aren't we past peak oil anyway?

Probably but I've just purchased 500 gallons of the stuff and plan to burn it in the next 18 months. (sod the next generation they can buy wooly jumpers)Thats about £11 per week. Happy days.
I could trim it off lower with better control like WC or TRVs but at the moment I am happy with the consumption.

We also have a strong objection to supporting nasty middle-eastern oil dictatorships if we can avoid it.

They receive a very small percentage.
You need to look closer to home where your own nasty dictatorship (aka labour) currently rules.


Have you added the cost of installing UF heating through out your home which is presumably heated by radiators at the moment. ?
Scary.
How well is the property insulated at the moment ?.

 

[JohnD]

some fossil fuels are used to generate electricity, and sell it at a profit

there are substantial losses in pumping the electricity from the power station to your home

so kWh for kWh, heat by electricity is more expensive and less efficient that having your own boiler.

For UFH heating, you need insulation under the floor. the cost and disruption of digging it up and installing it, in an existing building, will be substantial. I bet the cost of doing a single room would be more than the cost of repairing your oil tank.

Did your friends have it installed when their house was built?

 

[Caecilia]

GSHP - yes, we looked into it, together with a hydronic UFH system. We'd love to, but the cost is way outside our budget. There are essential works we have to do, like adapting the house for a wheelchair-bound person - widening all the doorways, adapting the bathroom, etc.

Insulation and draught proofing: This is all budgeted for; we have to pay for it ourselves as we're not eligible for any grants. It has to be done regardless of what we do about the heating. The house has a modern extension with insulation in the concrete floor, covered by a wooden parquet floor, currently carpeted over. That part of the house has a lower floor than the existing so raising the floor level with UFH and a floating wooden floor will actually be a benefit - the ceiling height is level with the original ceilings. The original part of the house (five rooms plus hall) has a suspended wood floor and will be properly insulated, joist ends insulated and each room sealed against leaks. We're doing it ourselves; it's hard work but not difficult; and the old inadequate kitchen will still be working while the new one's being fitted. Present plan: electric UFH will be installed over the original floorboards with an engineered wood floor on top, or we might re-floor with a decorative wood flooring of suitable floorboard weight and remove the original floorboards. It depends on the total cost. The original floorboards are solid oak - they were supplied by the timber merchant here in the village. We're ditching the carpets and installing engineered wood floors throughout regardless of what happens about the heating.

Oil heating: we've lived with it for 24 years, we haven't got used to the noise yet. Yes, we have radiators, and we loathe those too. Aesthetics play a part in this, our visual environment is important to us. The people who told us the boiler wasn't suitable for UFH were Bosch Worcester. If they're wrong we'd be prepared to look at it again, but there has to be some way of reducing the noise level. There's space for sound proofing around the boiler, and it's on a suspended floor so presumably ventilation could be provided through the floor if necessary. Because of the cost of the GSHP we didn't look at a hot water UFH system closely. The higher installation costs and the disruption do persuade us, at the moment, that electric is better for us. I'll contact some people tomorrow to give us some advice and costings on UFH with the oil boiler - thank you for the suggestion.

Inefficient power stations: Not our problem. We do what we can do and don't worry about what we can't. If we had a sensible government with a sensible policy on encouraging microgeneration we'd be investing in PV panels - we have 40 square metres of unshaded south facing roof, able to support the weight of the panels. Because so many people want to go green, the grants have been cut. A carrot and stick approach via the tax system would work, and encourage the industry; eventually higher production would reduce costs. And so on.

Friends house: it was retro-fitted; they insulated and draught proofed and ran the oil system for a year before they switched to UFH. I've lived with UFH in the U.S., it really is much more pleasant to live with than radiators.

Thank you all for your input, I really appreciate it. Now I have at least one alternative to look at, which is very helpful, and I'm grateful for the info on the existing system.

 

[JPH/01]

Your boiler will be fine for underfloor, I fitted one 18 months ago useing a thermal store to stop short cycling, the underfloor has a mixing valve to blend down to about half the boiler flow temperature. INMO anyone fitting electric underfloor out of choice is ill informed and will live to regrett it.

 

[Balenza]

GSHP - yes, we looked into it, together with a hydronic UFH system. We'd love to, but the cost is way outside our budget. There are essential works we have to do, like adapting the house for a wheelchair-bound person - widening all the doorways, adapting the bathroom, etc.

Insulation and draught proofing: This is all budgeted for; we have to pay for it ourselves as we're not eligible for any grants. It has to be done regardless of what we do about the heating. The house has a modern extension with insulation in the concrete floor, covered by a wooden parquet floor, currently carpeted over. That part of the house has a lower floor than the existing so raising the floor level with UFH and a floating wooden floor will actually be a benefit - the ceiling height is level with the original ceilings. The original part of the house (five rooms plus hall) has a suspended wood floor and will be properly insulated, joist ends insulated and each room sealed against leaks. We're doing it ourselves; it's hard work but not difficult; and the old inadequate kitchen will still be working while the new one's being fitted. Present plan: electric UFH will be installed over the original floorboards with an engineered wood floor on top, or we might re-floor with a decorative wood flooring of suitable floorboard weight and remove the original floorboards. It depends on the total cost. The original floorboards are solid oak - they were supplied by the timber merchant here in the village. We're ditching the carpets and installing engineered wood floors throughout regardless of what happens about the heating.

Oil heating: we've lived with it for 24 years, we haven't got used to the noise yet. Yes, we have radiators, and we loathe those too. Aesthetics play a part in this, our visual environment is important to us. The people who told us the boiler wasn't suitable for UFH were Bosch Worcester. If they're wrong we'd be prepared to look at it again, but there has to be some way of reducing the noise level. There's space for sound proofing around the boiler, and it's on a suspended floor so presumably ventilation could be provided through the floor if necessary. Because of the cost of the GSHP we didn't look at a hot water UFH system closely. The higher installation costs and the disruption do persuade us, at the moment, that electric is better for us. I'll contact some people tomorrow to give us some advice and costings on UFH with the oil boiler - thank you for the suggestion.

Inefficient power stations: Not our problem. We do what we can do and don't worry about what we can't. If we had a sensible government with a sensible policy on encouraging microgeneration we'd be investing in PV panels - we have 40 square metres of unshaded south facing roof, able to support the weight of the panels. Because so many people want to go green, the grants have been cut. A carrot and stick approach via the tax system would work, and encourage the industry; eventually higher production would reduce costs. And so on.

Friends house: it was retro-fitted; they insulated and draught proofed and ran the oil system for a year before they switched to UFH. I've lived with UFH in the U.S., it really is much more pleasant to live with than radiators.

Thank you all for your input, I really appreciate it. Now I have at least one alternative to look at, which is very helpful, and I'm grateful for the info on the existing system.

Have you considered the running cost of electric ?.
http://www.ukpower.co.uk/running-costs-elec.asp
Run this calculator with a 12 kw electric boiler and see what comes up.
Its almost £300 per month if you are running the heating 8 hours per day and that will only heat a small property.

How many sq meters are in your home ?.
How much are your friends spending on heating ? Do you know ?.
Is their home smaller or larger than yours ?. Perhaps its smaller ?
What about occupancy ?. Perhaps your friends have an economy tariff which works well as they are not heating the property during the day.
On the other hand you sound as if the property is occupied 24/7 and will need heat perhaps in some areas 24/7 and other areas perhaps for a high proportion of the time even during the daytime .
How much do you currently spend on heating your property ?.

 

[Caecilia]

Thanks for the link. I've bookmarked it for future use, but it's not a lot of use right now as the heating we're having to use now isn't going to be used in the long term.

Later... much later

 

[Balenza]

Caecilia wrote

Thanks for the link. I've bookmarked it for future use, but it's not a lot of use right now

Why do you think it is off no use ?.
Would you rather just spend thousands on installing electric UF heating and then receive the enormous bills for the running costs in order to know how much it will cost to run ?.

as the heating we're having to use now isn't going to be used in the long term.

I have gathered that much from your postings.
Go ahead , install the electric underfloor heating in your entire home.
I hope you will post back in the future and let us know how much your bank balance is being depleted each month.