New Gas Boiler - Worth it?

DorsetDude

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Hi

Had quotes to fit a "non-combi" boiler (its a condenser boiler), and also a quote for a combi boiler.

I currently have a 10 yeard old Glow worm boiler (50FF). The new ones would be worcester-bosch greenstar. The non combi one's a 15. I think the combi is a 21 or 22 junior.

£1700 odd to fit the non combi and 6 thermo rad valves

£2500 for the combi + valves as it has to be fitted on a different wall as wont fit in kitchen cupboard. Power flush included in both.

The plumber said I "wouldnt save much" by swapping from my current boiler to a new one so I am wondering if it is worth splashing out this sort of money on getting one? I just want to lower my monthly extortionate gas bill if I can.

There's only me at home so I thought a combi would be best. But then I loose lose my airing cupboard. Doh.

I am also having a gas fire fixed and serviced and the fireplace bloke reckoned that using the gas fire to heat the lounge and knocking the boiler heating thermostat back to 18° would be cheaper than heating the whole house to, say 21°. Would it? :shrug:

Grateful on any thoughts.

Confused of Dorsetshire
 
How's your insulation, double-glazing and draught proofing?

They'll all payback before a new boiler. And if you're hard-to-treat (solid wall, narrow cavity, remedial works required) or qualify from benefits the grants are back (under Eco, avoid Green Deal although Eco will have a GD assessment as part of it).
 
If you spend most of your time in the lounge then changing that gas fire for a high efficiency one would give you the best value for money.

Double glazing is a complete waste of money and will never pay back. It saves about £20 a year and earns b****r all points on an EPC. Thick curtains and frame sealant will achieve most of the saving!

A condensing high efficiency boiler earns the most points and will pay back if the current boiler is very old or inefficient. I don't think the gloworm is either. But you will save on leccy bill as you won't be heating water with electricity. Next is roof insulation. That's cheap to do and can save way more than double glazing for a fraction of the cost. Wall insulation is also worth considering if you have cavity walls.

I'd find a site which has the efficiency percentage for the glow worm and compare it with the others you are looking at. Unless new boiler saves you £200+ a year and will definitely last 10 years it will cost you rather than saving you money.

Finding a better and more programmable room thermostat and sticking thermostatic valves on all the radiators with the same boiler should also save a reasonable amount.
 
That's a tricky one because it depends on usage and other factors of your home.

If you saved about £300 per year then it will take you approx. 6-8 years to get your money back. (There is a psychological factor though that once you paid the money out and you see lower monthly costs you feel better.)

I doubt if you'd save that with a straight replacement boiler but with the combi the advantage is that you only heat the water you need but how much this saves is hard to say.

Depending on your house double glazing could set you back even more so payback could be longer. Insulation and draft proofing is a cheaper option I'd do this anyway but might not save you much in the long run.

I've never been a fan of thermo rad valves - they all seem useless to me and you finish up having them full up and balancing the system with the lock shield valves.

Personally if it ain't broke I'd stick with what you have and just improve insulation and draughts were possible. Fitting the gas fire seems a reasonable choice.

Colin

Colin
 
Combi boiler, cavity wall insulation and upping the loft insulation has saved us significantly in the last 3-4 years.
 
Insult-ulation_zps76872222.jpg
 
Save your money, if it helps I'm a gas engineer and do breakdowns for quite a few insurance companies, 75% (approx) of boilers I go to are condensing, mainly due to modern technology breaking down!
If your boiler is broke then fix it, if not and you're just getting a new boiler you'll never get your money back and as for the combi...forget it. Unless you're getting something with at least 13 to 14 litres a minute flow rate it'll take you half the night to fill the bath and even at that flow rate it'll still be slower than what you're used to.
If you are mind set on changing your best bet would be a heat only (normal) condensing boiler, something like a glow worm 18hxi and a unvented mains pressure hot water cylinder.
If it helps your existing boiler can be working at anything from 60-80% efficient, it depends on factors like how the heat exchanger is, any furring up, how we'll it has been maintained! pipe sizing and so on.... A new boiler will be around 97% efficient
If your old boiler is at its best you'll be saving 17%, work that out over 10 years as that's the stated expectancy of the life of a modern boiler (though no ones knows yet as most were install after 2005).
The first condensing boilers were made by Trisave.....they went bust ;)
 
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Thanks for the input all.

I already have loft insulation up to a decent height, was done on grant work last year. Gas bill was still horrendous last winter though :(
Double glazed already. Cavity wall not done I dont think but I am still dubious about this.

As has been mentioned, maybe use the gas fire more then and only get a new boiler if this one conks out.

Martyn: My hot water pressure is awful at the moment. I hoped a combi might increase the pressure so I could have a decent shower instead of the dribble I have now. Have investigated pumps etc but cant be done without smashing all the tiles off my bathroom wall and don't fancy that. What is this mains pressure cylinder you speak of?

Thanks.

[Oh and smug mode enabled with an IDJ cartoon in my thread! :woot:]
 
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I certainly wouldn't buy a new boiler unless the other one was broken. And even then, I would try to fix it first rather than replace. It's more kettle technology than rocket science and most parts can be replaced.

If you do replace it, a similar conventional boiler will be easier to fit as everything is already in the right place. A combi will need some re-organising and doesn't really add anything other than compactness.


Steve.
 
Seeing as i have a never ending supply of wooden pallets from work i just had to get a wood burner last year and had free heating all winter. :lol:
 
Seeing as i have a never ending supply of wooden pallets from work i just had to get a wood burner last year and had free heating all winter.

Perfect. Now add a heat exchanger and get free hot water as well.


Steve.
 
If you intend staying in the house for a fair time then the best thing to do is to make the heating into a sealed system with a new boiler and the unvented cylinder, this would remove tanks from the roof and make the system a lot more efficient, it's easy to think of an efficient boiler but as much and more can be saved on having an efficient system.
The cylinder is supplied directly from the mains with the pressure going in reduced to 3 bar, this then gives you near enough 3 bar of pressure coming out of your taps and shower.
Combis are ok but with the general run of the mill stuff like the Worcester juniors if someone is in the shower and someone else uses the hop tap then the shower user will get a bit of a shock from cooling waters. The majority are new houses are now going down the unvented cylinder route as it's now the in thing to have en-suites etc and trying to run 2 showers or even 2 taps at the same time off a combi, unless it has a pretty high glow rate, never works.
As an example...the Worcester junior 24 gives a flow rate of 9.8 litres a minute at 35 degree temperature rise, in the winter when the incoming mains is 10 degrees or less you'd need a 40 degree rise which would slow the flow rate down to below 8 litres a minute.
Bath taps run at around a flow rate of 22 litres a minute so it will take you 3 times as long to fill the bath.
 
Wood burner would be my next move. Had before in our last house.
 
On the subject of hot water pressure - when I had my boiler + tank I had the same problem and showers were crap - no real pressure at all. Now with the combi I get a proper shower with hot water at a good pressure - that on its own is worth the money personally speaking.

Other things - it's just me in the house too - early mornings - got instant hot water - rather than heating a whole tank and the just having a shower from it and wasting the rest.

Also I was able to get the new boiler installed where the tank was so that freed up room in the kitchen - and can still air clothes in the airing cupboard.

Is it going to pay for itself in pure cash terms - very unlikely - but from the other changes I'm very glad I swapped.
 
What sort of house / bungalow / flat? Detached / semi / terrace ?

How is your hot water heated? If your showers are "a dribble" is that because they are electric rather than running from a hot water tank, because you should get a reasonable shower if it is hot water tank fed. Not like a pumped shower but still not bad.

I have a 3 bed detached bungalow, gas averaged £50/month over a year to last month for heating and hot water. I have 11" / 275mm loft insulation (the current recommended amount IIRC), wall cavities insulated, double glazing and a nine year old combi boiler. I have no idea what it cost during the winter as I pay a fixed monthly DD, I have better things to do with my life than worry about remembering to pay bills every month / quarter when an automated way to do it exists :thumbs:. Remember that the winter was very long this year, the heating was on pretty much to June.
 
are you sure its a junior? if so you are going to be sold a boiler Worcester-Bosch no longer produce,they have dropped the junior from the Greenstar range,it now starts with the Si compact and Cdi compact. Not that there is anything wrong with the junior (other than no hot water temperature control at the boiler). If you have more than 1 bathroom a combi is unlikely to fit your needs unless you look at a higher output model,you will need to make sure you have enough flow rate of water at the cold tap before considering oany combi though. I don't give a rats backside if the boiler or cylinder will give 18 litres a minute of hot water,if it only has 10 litres a minute going into it,you cannot get any more than 10 litres a minute out of it.
 
Ditch the Worcester and go with a Vaillant boiler, an Ecotec plus 831 will give you great hot water delivery.
 
As you can see there are lots of options but anyone of thse is going to cost money to install. If you're prime aim is to save money as opposed to improving the system then you have to consider the pay back period.

If it's going to take 6-8 years to payback then you need to consider will it last that long; will you move etc.

You could improve hot water flow rate by installing a Pressurised Hot Water Tank. It feeds mains pressure cold water in at the bottom to force the hot water out at the same pressure. Still costs money though.

Colin
 
What sort of house / bungalow / flat? Detached / semi / terrace ?

How is your hot water heated? If your showers are "a dribble" is that because they are electric rather than running from a hot water tank, because you should get a reasonable shower if it is hot water tank fed. Not like a pumped shower but still not bad.

I have a 3 bed detached bungalow, gas averaged £50/month over a year to last month for heating and hot water. I have 11" / 275mm loft insulation (the current recommended amount IIRC), wall cavities insulated, double glazing and a nine year old combi boiler. I have no idea what it cost during the winter as I pay a fixed monthly DD, I have better things to do with my life than worry about remembering to pay bills every month / quarter when an automated way to do it exists :thumbs:. Remember that the winter was very long this year, the heating was on pretty much to June.

I agree with everything you have said and my bungalow is also as described, built in 2001. In 2010 i decided to refurbish the main bathroom and remove the the bath and install a much larger shower cubicle. All hot water is gravity fed, which wasn't that good for a satisfying shower. So, I installed a Digimix shower, which is a pumped system operated by a handset and that has made the world of difference. For anyone with a gravity fed hot water system, a pump is the answer.
 
Thanks for all the input everyone, very helpful. I'll address some questions below

If you intend staying in the house for a fair time then the best thing to do is to make the heating into a sealed system with a new boiler and the unvented cylinder, this would remove tanks from the roof and make the system a lot more efficient, it's easy to think of an efficient boiler but as much and more can be saved on having an efficient system.
The cylinder is supplied directly from the mains with the pressure going in reduced to 3 bar, this then gives you near enough 3 bar of pressure coming out of your taps and shower.
Had not heard of this option before, certainly something worth thinking about. Thanks

Combis are ok but with the general run of the mill stuff like the Worcester juniors if someone is in the shower and someone else uses the hop tap then the shower user will get a bit of a shock from cooling waters.
It is only me so that would not be a problem. It might for whoever moves in next but do I really care?

On the subject of hot water pressure - when I had my boiler + tank I had the same problem and showers were crap - no real pressure at all. Now with the combi I get a proper shower with hot water at a good pressure - that on its own is worth the money personally speaking.

Other things - it's just me in the house too - early mornings - got instant hot water - rather than heating a whole tank and the just having a shower from it and wasting the rest.

Also I was able to get the new boiler installed where the tank was so that freed up room in the kitchen - and can still air clothes in the airing cupboard.

Is it going to pay for itself in pure cash terms - very unlikely - but from the other changes I'm very glad I swapped.
Kind of agree with all this really. Now I have to decide if its worth £2500 for a nice shower plus other hidden costs of redecorating after the work I expect.

What sort of house / bungalow / flat? Detached / semi / terrace ?
Bungalow with hot water cylinder on same level as bathroom. Hot water flow is basically crap.

How is your hot water heated?
By the gas boiler.

If your showers are "a dribble" is that because they are electric rather than running from a hot water tank, because you should get a reasonable shower if it is hot water tank fed. Not like a pumped shower but still not bad.
Depends what you think reasonable is. I can manage but would prefer slightly more force.


are you sure its a junior? if so you are going to be sold a boiler Worcester-Bosch no longer produce,they have dropped the junior from the Greenstar range,it now starts with the Si compact and Cdi compact.
I just checked the quote and yes, it's a28i junior. Doesnt sound too good then does it.

If you have more than 1 bathroom a combi is unlikely to fit your needs
I just have the one bathroom, no ensuites or anything.

Beginning to think this sealed system with mains powered hot water cylinder might be an idea and to wait until the boiler is broken before changing.

Would it be worth me just fitting thermostatic rad valves in the meantime?

another question: In the depths of winter is it more efficient to leave the heating on 24/7, say at 18° to keep the house warm rather than letting the house cool down all day/overnight and then running the heating to get it back up to warm again when you get home?

Cheers all.
 
If your house is well insulated just let it come on twice a day just before you get up and return home

Many years ago my first house needed completely refurbishing,there was no heating other than a calor gas fire

Despite being on for hours it barely warmed the house at all because everything was cold, floors walls and ceilings

A modern insulated house will hold a high proportion of heat so just needs a top up to get back to a comfortable warmth
 
Ditch the Worcester and go with a Vaillant boiler, an Ecotec plus 831 will give you great hot water delivery.

We had that boiler fitted in Jan 2011, replacing a 22 year old combi boiler which finally caved in December 2010. Cost was £2,000 for supply and fit with a full system power flush. The rest of the system, now 25 years old, was unaltered. In almost three years with the new boiler the performance has been faultless so far.

We have a 3 bed semi, solid brick walls, fairly well insulated loft and double glazing. Heating is left on 24x7 (the house is occupied most of the day every day) with the main thermostat regulating whether or not it comes on. The thermostat has a timer to set different target temperatures at various times during the day/night. Typically we have it set for 18C or 18.5C during the day, dropping to 17C or 16.5C overnight. When pansies come to visit we might crank it up to 19C or 20C temporarily. We shut off rarely used rooms - one bedroom and the dining room - and leave the rads turned way down when the rooms are unused. So far we have yet to see bills exceed £1,000 for the year for gas and electricity combined. In round figures the annual cost breakdown is £350 for electricity and £650 for gas on a fixed price plan till April 2014 with EDF.

I have read that using any sort of fire in a centrally heated property is counter-productive, financially speaking, as you are burning air you've already heated and chucking it straight up the chimney. I have no idea how true that is, but it makes sense to me. We have a gas fire in the living room and the only time we've used it is when the old boiler broke down in December 2010 and we had to wait over a week for parts to tide us over until the new boiler was fitted.
 
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