Which Oil Boiler....?

[Boxerman]

to replace an Worcester Danesmoor 12/14 boiler. The boiler is in good working order but is in a cupboard in the middle of the house and kicks out so much heat that I presume it's running quite inefficiently and therefore costing me quite a bit in fuel (approx 3500 ltrs/year)

The new boiler will have to comfortably run 13 rads and maybe even some extra underfloor heating if I decide not to go with an additional groundsource system.

Any thoughts on gravity v's combi or other system types, opinions welcome

 

[Nixt]

Your current boiler is only capable of 47,000Btu/h so if you have 13 rads and HW it may be undersized. This would mean it struggles to reach temperature and always runs (without cycling) during CH on period. Either that or it's set up incorrectly. The other issue to check is heat loss from your home. 3500ltr pa seems almost impossible for the boiler output in normal operation.

As for today's condensing oil boilers, I think they're all sh*te. A bolt on recuperator to standard mild steel exchanger, changed my first rotted one in 2004 (not fitted by me).

 

[Boxerman]

heat loss from the home is quite high as it is solid wall construction and insulating internally is not an option until I can source original features such as coving. The loft is well insulated @ 250mm.

So a larger boiler looks like it's required but I am stuck with oil as there's no mains gas where I live. To be fair all the rads get hot, although they could do with upgrading as they're old too.

 

[Nixt]

Then oil it is. However look at some secondary heating like a dry stove to take the sting out of running the CH. With a well insulated modern cylinder you can cut down on oil use in winter. Avoid oil combi's, they use the same components as their gas counterparts only at much higher operating temperatures which tends to shorten their working life.

 

[Boxerman]

well I have a coal fire and am due to install a multi-fuel stove too (although more for aesthetics to keep the Mrs happy), am I perhaps better sticking with my current boiler until it expires ?

 

[Nixt]

It's your choice, I'd say stick with it and think through alternatives long term. Oil is fine if already installed but to renew today means bunded tanks and condensing boilers added to the fuel price, which has trebled since 2004 - An industry in terminal decline.

 

[Kes]

Sedbuk thinks that the Danesmoors are 85% efficient, so the step up to condensing isn't that great. At least your boiler is in the middle of the room so that the heat it gives off isn't wasted.

We have a Danesmoor 26/32 (can't remember the actual numbers) and we use around 2500 ltrs a year, also in a large solid-walled not very well insulated house. The boiler heats 14 rads. Of course usage affects consumption, I can see 3500 ltrs being used if the house is heated all day to a highish temp. We use the immersion heater for h/w in the summer.

The Danesmoors are still advertised, can you still fit them legally?

 

[oilman]

SEDBUK for Danesmoors is rubbish, they are always a lot better.

You do not need to change the boiler, just provide some more insulation round it, put some insulation round the pipes which don't have any, the rest of the heat is probably from the flue pipe. You could insulate it, or you could ventilate the cupboard so the heat comes out into the rooms.

With that size of boiler it is capable of exceeding the heat carrying capacity of 22mm pipe. If your pipes are not bigger than that, a bigger boiler is pointless.

14 radiators is a meaningless figure unless you say how big they are.

Even if the boiler and radiators were the "correct" calculated size, the outside temperature and thus the heat need from the boiler varies through the year. If it was designed for the coldest expected temperature, that output would be needed for only 11 days per year.

You don't say what temperature you have your thermostat set to.

You don't know what heat is being produced by the boiler, you only know the temperature in the cupboard is high. The heat in the cupboard will eventually get into the house, so it is not wasted.

 

[oilman]

An industry in terminal decline.

Oftec have just committed £250,000 to vegetable oil research, so you will at least be warm while you starve as all the food is fed to your boiler.

 

[Nixt]

Oftec have just committed £250,000 to vegetable oil research, so you will at least be warm while you starve as all the food is fed to your boiler.

All they need to do now is work out how to stop it freezing in winter or suffering biological growths in summer. Apparently in Germany they store rapeseed oil for fuel in indoor tanks what a dilemma that'll give OFTEC.

 

[htgeng]

I looked at the specs for the Viessmann oil boiler a couple of years ago but was told they didn't sell it in the UK. Their website now suggests they do, but with a statement Please note: this boiler requires oil with a sulphur content of less than 500ppm.

Can any of our esteemed oil experts say if this is an issue with oil sold here?

http://www.viessmann.co.uk/index.php?content=product&model=Vitoplus-300

 

[simond]

Yes it is. Viessmann will only let you use low sulphur fuel and this is very scarce. Kerosene in the UK has a minimum of 100ppm since Jan 2008 (it was typically 600ppm before, I believe).

The rest of their range use red diesel (35 sec) so this isn't good news either.

Otherwise we'd be fitting them

 

[Kes]

Wouldn't it be more correct, oh what the hell. correct, to say that since Jan this year the maximum sulphur content in heating oil supplied in the EU is 1000 ppm? (Down from 2000.)

The OP could call a few local suppliers. I would think that most quality suppliers have relatively low sulphur content already. Texaco, f'rinstance, say that their oil has 500 ppm sulphur. I can only see sulphur content being reduced in future (Germany is moving towards 50 ppm).

 

[simond]

Sorry, I mistyped and missed a nought off. I meant 6000ppm down to 1000ppm.

The net result is the same, you have to acquire a special ultra low sulphur kerosene (not widely available in the UK) if you want to run the Viessmann and even then you are restricted to just one small wall hung unit.

All their other boilers run on 35sec diesel and none of those are Sedbuk A.

 

[Boxerman]

Just realised that I actually have 15 rads running of it but they all seem to get hot and the house warms up nicely after about an hour.

The boiler heat is from the flue which then extends up through an insulated 25ft stainless steel 'chimney' on the outside of the house. It's a bit of an eyesore and another part of my thinking that I could change the boiler and lose this particularly ugly feature.

My only options for fuel in my village are oil and bottled/tank gas and the gas option would cost a load more to run on current prices.

I think that long term the ground source heating may be the way to go but the initial installation costs are still high, and air heat exchanges are also pricey whilst getting more efficient @ 450-500%.

And solar hot water is the other option but again it's still too expensive to install.