Are oil condenser boilers very cost efficetn as regards oil?

justaquestion

Hi,

I have an old oil boiler system for central heating, I got it serviced recently and asked the service guy to do some tests, he said that the boiler is just over 90% efficient, carbon monoxide count was just over 30 parts per million, within the safety range of 50 parts per million.

He then on to say that though the boiler has a good efficiency percentage, that I would probably save up to a third in oil consumption changing to a condenser boiler system.

Overall I think I am not that sore on oil usually 2000 litres a year does me, though would be grateful for any advice from those who have changed over to a condenser system, if the saving on oil can be really a third?

They are quite expensive to install as well, £13-1400, even taking into consideration any warm home grant to do so.

Any advice appreciated.

Owain_Moneysaver

Check the SEDBUK database for your boiler's actual efficiency rating.

If it's already 90% efficient it's probably already a condensing boiler, and you're unlikely to get anything a lot more efficient.

You may be better improving insulation and upgrading controls eg programmable thermostat and rad valves.

And also shopping around for oil - if you and your neighbours group together to purchase in bulk you may get a cheaper rate as the tanker only has to visit once.

justaquestion

Thanks for reply.

No its not a condenser boiler its one of the old cast iron type probably in house since it was built 30 years ago, the burner part was replaced about 15 years ago and seems to be running ok.

In the past the guys who serviced the boiler seemed to be impressed with it, said the boiler part was like something you would see in a guest house or something like that, never really had much trouble with it.

But of course time moves on and I do hear great things about condenser boilers especially the Grant brand.

What I find a little hard to understand is if the boiler is over 90% efficient then how could I save up to a third on oil with a condenser boiler?

Thanks again.

Davesnave

It's very unlikely an older non-condensing boiler would get above 70% efficiency. Modern condensing boilers might achieve around 92%.

The info you've been given about your boiler is just wrong.

kinger101

Replacing a functioning boiler is very rarely economical. If you spend £1,000 a year now on oil with a boiler that's say 70% efficient, crude back of envelope stuff tells me that would fall to about £775 with a 90% efficient boiler.

Improving the controls like suggested sounds a better improvement, depending on your lifestyle.

TBH - sounds likes the oil equivalent of the British Gas service. Encouraging people to replace perfectly good boilers to get a commission.

Davesnave

kinger101 wrote: »

TBH - sounds likes the oil equivalent of the British Gas service. Encouraging people to replace perfectly good boilers to get a commission.

Although the figure quoted for existing efficiency destroyed any argument for replacement....

Very odd!

DaftyDuck

I suspect the oily engineer may have confused the data on burn efficiency with boiler water heating efficiency. You will get a much greater conversion efficiency from a new boiler.... Whether it is financially or environmentally worthwhile is more difficult to estimate.

However, your old boiler is unlikely to hit 90%, more likely a bit below 80% at best. If it is a commercial scale boiler it may well be built to last. You say previous servicers were positive about it: any chance of getting one of them back? Otherwise, contact some local small boiler installers for a quote. Like gas, local tends to be best for advice and cheapest.

Gotta rush... I have to take a sink out, prepare and paint walls, then told the floor of the utility room... My new Grant boiler install starts tomorrow at 9. D'ya think I'll finish in time? Probably not! :rotfl:

Davesnave

I'm pleased with my Grant boiler. When supervising the the install, make sure the condensate pipe doesn't go where it can freeze-up easily....err, like mine does at present. Changing that!

glentoran99

Davesnave wrote: »

I'm pleased with my Grant boiler. When supervising the the install, make sure the condensate pipe doesn't go where it can freeze-up easily....err, like mine does at present. Changing that!

Mine has a failsafe that if temperature falls below 5oc it automatically comes on to prevent freezing

Davesnave

glentoran99 wrote: »

Mine has a failsafe that if temperature falls below 5oc it automatically comes on to prevent freezing

If the condensate pipe is out of doors and the temperature falls to, say, -10c, the condensate will freeze in the pipe.

Once the pipe freezes up, you will have a 'fail safe' that shuts the boiler down!

glentoran99

Davesnave wrote: »

If the condensate pipe is out of doors and the temperature falls to, say, -10c, the condensate will freeze in the pipe.

Once the pipe freezes up, you will have a 'fail safe' that shuts the boiler down!

I know nothing about this but wouldn't the boiler being constantly on from 5c keep hot condensate flowing through the pipe preventing freezing?