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Central Heating Systems

Leapy
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Central Heating Systems

I have a very old basic (but functional) conventional gas central heating and hot water system and also do some cooking by gas. However I'm told my boiler is only 69% efficient. Sad 

Thanks to a British Gas smart meter (and thermostatic radiator valves) I can tell you the following about my gas usage:Smiley

YEAR     COST     KWh     MAX     AVE     MIN

2015      £544       10.7k     £68       £45       £21

2016      £520       12.0k     £90       £43       £19

2017      £184       05.6k     £75       £36       £18 (Jan -May Inc.)

So, is it worth upgrading my boiler to one that is say 90% efficient to maybe lower the gas cost/usage by around 20% pa (say @£100pa) or should I just live with what I've got or look at other forms of heating?

 

The pub is two minutes from my home, although my home is two hours from the pub,
16 REPLIES
St3
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Re: Central Heating Systems

Buy a new one ... go for baxi duo tech this is what i got Wink 

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alanf
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Re: Central Heating Systems

Assuming best case and all gas was used for hot water/heating and the figures exclude any standing charges...

Last year £520.

With change of boiler that should reduce to £520*69/90=£399 a saving of £121 per year if prices are unchanged. How much for a new boiler being fitted £2K? £4K?... The new boiler will be scrapped before it has paid for itself.

My Mum had an old boiler replaced because British Gas said that parts would be unavailable. The figure that they quoted for the savings with a new boiler were totally bogus. The old boiler gave very few problems. The new one over the past seven years has required engineers out to replace parts several times most recently the heat exchanger.

There may be good reasons for replacing a boiler but increased efficiency is not one of them.

Leapy
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Re: Central Heating Systems

@St3 is that the platinum ?

The pub is two minutes from my home, although my home is two hours from the pub,
Leapy
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Re: Central Heating Systems

The guy next door has stripped out his entire central heating system and replaced it with electric underfloor heating! Shocked

He says it cheaper? Undecided and  he can add vale to his home without central heating Roll eyes as no clutter from radiators, pipes, boiler, hot water emersion tank or loft tanks, he can use the extra space and put in a shower and 2nd loo! Undecided

The pub is two minutes from my home, although my home is two hours from the pub,
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Re: Central Heating Systems

I'm in the same position, our boiler is over 25 years old. Not much gone wrong with it over the years apart from the flame sensor.
It isn't really worth it to replace it until it needs replaced.
Next door had a new one fitted a few years ago (local housing ass.) it was REPLACED again last year.
So you need to look at them really closely as you will NEED to pay for servicing each year to keep the warranty up.
alanf
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Re: Central Heating Systems

I used to work in a place with underfloor heating. Not good for the feet.

 

 

ffox
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Re: Central Heating Systems

A neighbour replaced their boiler about 10 years ago.  Several repairs were needed over the years. Last year the boiler broke irretrievably and has been replaced.  Over the same period our old boiler has been maintained (not by British Gas) via yearly visits - no replacement parts have been needed.  I reckon we have saved £2000+ by not having a new boiler!

@Leapy  How does your guy heat his water?

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Re: Central Heating Systems


Leapy wrote:

The guy next door has stripped out his entire central heating system and replaced it with electric underfloor heating!


We put in circulated water underfloor heating, but for it to be efficient we also installed about 25 cm of foam insulation under the floor slab otherwise a lot of the heat is wasted into the ground.  Per KWH electricity is about three times more expensive than gas or wood pellet because you are paying for those funny windmills and nuclear decommissioning with electricity.  While a gas fired boiler based central heating has high capital costs, the running costs of underfloor electric heating can be high, particularly if you don't have underfloor insulation.

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Leapy
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Re: Central Heating Systems

Thanks for all the feedback so far, please keep it coming as its a  very challenging subject (well for me) Wink

I was also told that because my boiler is non-pressurised, I should also change the radiators (and piping) as they may not take the pressure of a new boiler :sad Undecided

As well as that, because my boiler is on the ground floor, in a lined chimney, it is now too long for building regulations and I need to move the boiler (and all related pipe works) to a new location, like in the loft or an outside wall! SadUndecided 

Does anyone know if a solar or air or ground source heat pump, worth considering? 

The pub is two minutes from my home, although my home is two hours from the pub,
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Re: Central Heating Systems


Leapy wrote:

I was also told that because my boiler is non-pressurised, I should also change the radiators (and piping) as they may not take the pressure of a new boiler :sad Undecided:


 

Our heating system is probably older than me, and it used to be a gravity-fed system at one point going by the header tank still in place (but disconnected and disused), when I got the previous boiler working (99p CR2032 battery, versus tooth-sucking conman of a repairman saying £80+ for a new £15 timer, plus labour costs!!!), there were a couple of leaky valves after I repressurised the system, but a tweak with a spanner on the nut around the valvestem cured that, and even with the new boiler that was put in back in 2015, it's remained leak-free, the pressure's not as bad as they make out, just about 1-1.5 Bar, so unless you have poorly soldered pipe joints, it'll be fine, they're just trying to make more work to extract more money from you...

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Re: Central Heating Systems

I suspect you need some alternate quotes from other vendors/plumbers.

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St3
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Re: Central Heating Systems

The thing is boilers dont last forever and when they start with problem after problem somtimes its better to get a new one. I had a baxi installed 7 year ago cost me around 800 quid im still using it today without any problems. Most new baxis come with these now http://www.screwfix.com/p/adey-cp1-03-00022-01-2-magnetic-filtration-22mm/49961 which help to filter out dirt that builds up inside your heating pipes these also prelong the life of the boiler. 

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Re: Central Heating Systems

Most high efficiency 'condensing' boilers will struggle to condense well on an existing system unless the radiators are generously sized so, when used as replacements for existing boilers, they do not achieve the claimed efficiency levels.  Some are better than others but most will loose efficiency if water coming back to the boiler is anywhere near 70°C (which is not untypical for the design of an older system).

Most modern boilers will not last nearly as long as the older ones did so, as others have pointed out, they will not 'pay' for themselves before they see the scrapyard (and that may be as bad for the environment as burning that (little?) bit extra gas.

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Leapy
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Re: Central Heating Systems

A long time ago, I worked for Thomas De La Rue, whom owned Thomas Potterton (of Potterton / Baxi boilers fame).

In Warwick and Wandsworth they had stockyards full of boiler core castings, "weathering and conditioning" before assembly and testing. I know this is very old school, but are new boilers made in the same way or are they more like the old fashion multi-point gas water heater? https://www.plumbnation.co.uk/site/main-multipoint-bf-water-heater-erp/ 

The pub is two minutes from my home, although my home is two hours from the pub,