Advice on replacing ancient boiler

napu2400

Hello. I'm asking for some advice as I am new to mains gas boilers.

Our house has a really old boiler, probably from the 70's. It still works, which is impressive, but it's probably really inefficient. Also according to the last service, parts aren't available any more. So we looking to replace it.

The rests of the system consists of a hot water tank in the airing cupboard upstairs with a fairly modern digital timer and electric valves that turn the heating and hot tap water on and off.

I think our options are:
A) Replace just the boiler with a more efficient regular one and leave the rest in place. Maybe add a thermostat.

Change to a combi-boiler. I think we could then get rid of the tank and reclaim some space. Would this cost a lot and would we have to tear up the floor to change pipes?

System

You need advice as any replacement boiler needs to match your property and heating/hot water demands. It may be that a combi would work but only an installer can advise you. Also heating upgrades have to comply with the latest building regulations which I think requires the fitting of TRVs to each of the radiators.

As far as cost is concerned, then only an installer can advise. I would have thought, for example, your radiators will need a power flush. Without one, then there is a real danger that your brand new boiler will fail due to a blockage. This may invalidate your warranty.

My advice would be to get three quotes from approved installers.

napu2400

Thanks. I'm just looking for some advice so I know what to ask the installer, and know what is reasonable.

footyguy

napu2400 wrote: »

Hello. I'm asking for some advice as I am new to mains gas boilers.

Our house has a really old boiler, probably from the 70's. It still works, which is impressive, but it's probably really inefficient. Also according to the last service, parts aren't available any more. So we looking to replace it.

The rests of the system consists of a hot water tank in the airing cupboard upstairs with a fairly modern digital timer and electric valves that turn the heating and hot tap water on and off.

I think our options are:
A) Replace just the boiler with a more efficient regular one and leave the rest in place. Maybe add a thermostat.

Change to a combi-boiler. I think we could then get rid of the tank and reclaim some space. Would this cost a lot and would we have to tear up the floor to change pipes?

If it's not broke, don't fix it!

As for parts being unavailable, cross that bridge when you get to it. As you only are relying on a service report for this info, then obviously you have not needed any new parts for quite some time

zaax

Old cast iron boilers are more economic that the newer ones as they have no moving parts and all they need is an annual clean and the poilet light de-coked, and they last for decades. On the otherhand new boilers are designed to last only 10 to 12 years, because of fan motors and eletronics etc. (and they say they are ecofriendly). Keep the old boiler until you can't get parts.

McKneff

We don't have a combination boiler but we have a warm air system with a boiler attached. This was ptarmigan in 16 years ago and took nearly 2 hors to heat water for a bath .

New system this year, still warm air heating but just 3 minutes for a bashful of really hot water for a bath and more,.... brilliant

McKneff

Thirty minutes

matelodave

I'd keep the old one going for as long as you can and start saving for it's replacement. There's hardly anything to go wrong in an old cast iron boiler - a gas valve, thermocouple, burner and thermostat, non of which are expensive and usually fairly standard.

A new one will require access to an outside wall & drain for the condensate and it will be filled with electronics and other complex items which don't last as long and cost lots to replace.

The old one may not be as efficient but it will cost at least £2k, probably more to replace it. Even if you saved £200 a year on your gas bill it would take 10 years to pay back and you'd have probably had a couple of expensive repairs on the new one by then as well.

You'd probably be better off improving your insulation, draught proofing and upgrading any heating controls like installing a programmable room thermostat, make sure you've got a stat on your hot water tank and TRV's if you don't have them.

C_Mababejive

OP..make and model please?

napu2400

The boiler is a Glow-worm Spacesaver. I'm not sure of the exact model number. We just bought the house, so I don't know how reliable it has been in the past.

tacpot12

Parts are available for the Glowworm Spacesaver, but they are getting very expensive. The last fan I bought for our Spacesaver KFB 70 was about £250. The fan wear out about every four or five years. The rest of the boiler will last a long time, and should be reliable. I would buy a fan now before the prices do up again, while you start saving for it's eventual replacement.

Combi boilers are good if you don't need a lot of hot water, e.g. Everyone prefers showers to baths and you have an electric shower. If you have a shower that doesn't heat its own water, I personally wouldn't have a combi.

I'm a big fan of combis. You will save the space of the three water tanks you have currently if you switch, but in my experience they only last about 15 years, so they are not such good value.