Options for new boiler.

[RPerrin]

Hi guys.
It's time to change our 20+ year old boiler, and I'm looking at options.

We currently run an oil combi, as there are no mains services in our village, and I was initially looking to replace with another oil boiler. We've had a quote of just over £5K to replace the boiler with a Worcester Bosch Greenstar Heatslave II 25/32, and new valves on the 8 radiators. However, with the price of oil, future supply issues, and the possible need to replace the decaying tank at some point, I want to investigate the other options available.

I've kind of dismissed LPG, as it has the same problems as oil, which seems to leave biomass or electric.

We have a 3 bed semi, built in the 1940's, so not the best with respect to insulation. We did have cavity wall insulation blown in some years ago, but I'm not sure if it made much difference. We have one bathroom currently, but will probably convert part of the utility to a second at some point. The bathroom has an electric shower, bath and sink, and the second bathroom, when we get to it, will have a shower and basin only. There's only me and my wife, so not a massive demand for hot water at any one time.

Biomass appears to be expensive, although it does qualify for various grants (apparently). Then there's the sourcing and storage of the fuel itself, and the additional maintenance, so this isn't at the top of my list.

So that seems to leave heat pumps, which again are expensive or an electric combi. I know electricity is currently expensive, but this appears to have a better chance of becoming cheaper over time (possibly?)

I'd be grateful for your thoughts on how best to go. I'm sure I have a more simplistic view than those in the know .

Thanks guys.

 

[winston1]

I doubt electricity will get cheaper. 60 years ago it was double the cost of gas. Over the years since the differential has gradually widened to the current 4 times as much. Remember much electricity to generated from gas.

I think a heat pump is your best solution.

 

[ericmark]

20+ year old boiler is not old for oil.

There are multi-fuel systems that can combine solar, oil, electric etc. But the main way is to use a heat exchanger/store, a big tank with loads of coils so energy sources can be combined.

Seems great, until you look at the price, starting around £12k, brother-in-law had it in last house and it does work, he would go to Germany for a few weeks, the geofencing detected him on the way home, and got the house nice and warm for him to walk into.

However when he moved, he decided it would never pay for its self at his age, 71 same as me.

Using electric solar panels it would keep the old house warm enough to stop anything freezing while away, and the store was hot enough to reheat house for return, but once home needed to light a fire most evenings to top up heat store, it would be lit and then allowed to burn out, he had gauges to show how much heat in store.

The pellet burner has become popular, as it is automatic, but the price of pellets has also changed year to year, the stalks from growing wheat and barley ect are no longer burnt on the field but turned into pellets, bit like the stuff used for cats to do there stuff in, but like the waste oil from chip fryers which at one time cost to get rid of, now there is a shortage.

It seems the heritage railways are also having a problem, south Wales steam coal is drying up, and the Polish stuff is rubbish, Talyllyn railway has been experimenting with composite briskets to replace the coal from Ffos-y-fran, Merthyr Tydfil after their washing plant went wrong resulting in a faster than planned loss of Welsh steam coal.

So whole energy system is in turmoil, as it stands no one knows what the future will bring, including the November 1978 and February 1979 Winter of discontent being repeated as the UK national grid has all the extra load after closing down so many fossil fuel power stations.

 

[muggles]

Stick with the oil. Direct electric will cost 3-4 times as much to run, electric combi boilers are crap, and converting to a heat pump will likely be too expensive. No reason to replace your existing boiler unless it's leaking from the main heat exchanger

 

[diynoob]

I'd wait until the boiler dies before changing it. There's only about 40 years of oil left https://www.worldometers.info/ so you'd think it will continue to get more expensive as demand outstrips supply. Industries and vehicles will use less oil in the future though so who knows. Electricity can be generated by many means so I'd expect electricity to get cheaper but that hasn't happened so far.

Oil is currently 110p per litre, which is about 12.8p per kWh. The electricity price cap from April will be 28p per kWh so oil is still a far cheaper option.

 

[RPerrin]

Thanks for the replies everyone.
The current boiler leaks everywhere, and is extremely rusty, although heat exchanger is still intact. Getting parts is quite expensive too, with some obsolete. Old Potterton Statesman Flowsure. My usual heating guy is reluctant to touch it, cos a stud? broke off when he last tried to service it.
I could probably rebuild the water side myself, but already had some cash put aside for a replacement.

 

[RPerrin]

Ok, I have a concern with the WB option. I specifically asked the supplier about the heat exchanger, and was it was made from stainless steel. A simple Google told me it's actually aluminium. They are offering a 7 year warranty.

I've also looked at Grant combi's, which do have a stainless HE, and a similar warranty and, depending on the installer, 10 years. The boiler is a bit more expensive though.

It's difficult to decide which way to go, as each company will obviously favour their own.

I'm sure you guys too will have your preference, but can you offer any advice, based on your own experiences? I.e, common faults and likely life span? I know it's all subjective, but it would be useful to have ideas from engineers who work on them.

Thanks again.

 

[flameport]

So that seems to leave heat pumps, which again are expensive or an electric combi.

If you go electric, then a heat pump is the only sensible option.

Electric combi boilers exist but they will have feeble performance and cost a fortune to operate, and that assumes your electricity supply is actually suitable for one - many are not.

 

[muggles]

Ok, I have a concern with the WB option. I specifically asked the supplier about the heat exchanger, and was it was made from stainless steel. A simple Google told me it's actually aluminium. They are offering a 7 year warranty.

I've also looked at Grant combi's, which do have a stainless HE

No they don't, or at least none of the ones I've ever come across do. Secondary might be stainless but the primary heat exchanger is still mild steel. The only fully stainless oil fired combi boiler I know of is the Navien LCB700, which comes with a 10 year warranty.

 

[RPerrin]

Thanks Muggles. Not easy for us mortals
What would you recommend for approx £5K budget? I think you are reasonably close to me too. The Installer I'm looking at offers a 7 year warranty on the WB.

 

[muggles]

I'd go for the Navien - not as much plastic in them as a WB for a start, two-stage burner helps to keep fuel consumption down, as does their smart thermostat which varies the flow temperature according to your home's needs. Worth considering spares prices too - as an example the WB's PCB is about £450 if it goes wrong out of warranty, Navien's is less than half that

 

[Mottie]

The three most common designs are regular, system, and condensing

Wouldn't the first two also be condensing anyway?

 

[bernardgreen]

Wouldn't the first two also be condensing anyway?

Yes they would be in the UK, but in the USA it is not ( as far as I know ) compulsory to use only condensing boilers.

 

[Mottie]

Yes they would be in the UK, but in the USA it is not ( as far as I know ) compulsory to use only condensing boilers.

But they are giving that advice to a U.K. member of a U.K. forum. They might as well be telling us we should be driving on the other side of the road.