Do I bite the bullet and go for a Combi?

[zetland76]

I currently have a gravity hot water system and pumped central heating fed from a conventional boiler. The galvanised water tank is in the airing cupboard above the hot water cylinder. The tank is quite old and might begin to leak. I’ve got a new plastic tank from my neighbour. I plan to use it to replace the old tank but move it into the loft. The CH top up tank is in the loft and I will replace this at the same time (this is also galvanised). I’m retired so this job will cost me less than £50 in materials.
Unfortunately whilst checking the cylinder I found the heater coil joints corroded so this will need to be sorted in the near future. I’m now talking £250 plus for a new cylinder and a slightly more difficult job to tackle myself.
The whole system currently works fine but do you think it’s time to fork out £2000 plus to replace it with a combi?

Thanks

Mike

 

[Agile]

You have not given details of your existing boiler so we cannot give you informed advice.

I would say dont go for a combi unless you have special needs for one.

Nor would I expect there is any need to replace the hot water cylinder yet if there are no leaks. A photo would help.

Replacing old galvanised cisterns are a good idea though as they can fail at any time and the extra head from the loft will be a big advantage.

The outlet should really be in 28 mm down to the cylinder. Its recommended in a british standard but often ignored by plumbers.

If you are retired but fit why not ask if you can do a few hours a week with a local plumber as a low paid helper or driver? An extra pair of hands without any on going committment is often very useful. All the retired people doing nothing are a wasted asset!

Tony

 

[gas_man_gaz]

if you are needing the cylinder replacing you will also need it converting to incorporate some sort of temp control at the same time (energy eff regs)
ya dont mention what boiler you have? the system could deff do with upgrading tho

 

[zetland76]

My boiler is a GlowWorm SpaceSaver 50 and could be up to 25 years old. The Corgi guy who serviced it last year said that they are good boilers.
Unfortunately the corroded connections are round the back of the cylinder and I can't get to them for a photo (found it by feel when I was putting on new cylinder jacket). If I replace it I will cut through the egg-box wall from the built in wardrobe to get access to the back of the cylinder.
Yes! The existing cold water feed uses a 28mm pipe. In fact as far as I can see any pipe close to or joining the cylinder that isn't 15mm is 28mm. I don't think there are any 22mm. Bit of a b*gger as 28mm stuff is more expensive than the 22mm stuff.

Mike

 

[heytesto]

If you plan to change the cylinder, I would bite the bullet and fit a decent combi. Your cylinder and storage cistern are probably older than the boiler.

Get it all changed and your controls updating, you won't regret it. Just check you cold water mains flow rate will support a combi.

 

[bengasman]

...Get it all changed and your controls updating, you won't regret it...

I would agree with the above, but only provided you get a good boiler, and even more important, and excellent installer.

 

[oilman]

But sooner or later you will wish you didn't fit a combi. When it stops there is NO backup.

 

[heytesto]

But sooner or later you will wish you didn't fit a combi. When it stops there is NO backup.

Complete nonsense, I repair nearly every boiler on the day or in 24hrs if parts are not in stock.

Add to that, I only fit reliable boilers and in the unlikely event of a fault, parts are always available.

Typical scaremongering if you ask me. Some people have had bad experiences with combis, usually down to a poor boiler choice or poor installation.

Especially when you consider half the new houses in the last 25 years may have a cylinder, but the immersion tapping is plugged off.

 

[mickyg]

But sooner or later you will wish you didn't fit a combi. When it stops there is NO backup.

you could always fit one of these
http://www.glow-worm.co.uk/products/ultrapower_sxi.asp

 

[oilman]

Complete nonsense, I repair nearly every boiler on the day or in 24hrs if parts are not in stock.

Very commendable, but are you going to be repairing zetland76's boiler? And is that on the day you get called? If so it will probably be a long trip.

 

[heytesto]

Complete nonsense, I repair nearly every boiler on the day or in 24hrs if parts are not in stock.

Very commendable, but are you going to be repairing zetland76's boiler? And is that on the day you get called? If so it will probably be a long trip.

Yes that is the day I get called. Existing customers always take priority. I always look after my own installations.

Oh, and Zetland in Yorkshire isn't that far. Infact, I could be in N. Yorkshire in
15 minutes.

Also, that is precisely why zetland76 should select boiler and installer very carefully. There really are some s-hite installers up north. (and down south)

 

[Agile]

Odd that nobody has specifically joined me in saying that a combi is NOT a good idea unless there are specific advantages in having one.

I also specialise in repairing boilers and go the same day in about 95% of cases when I am advised by 1130 am as long as the client is available. I also expect to get over 95% working on that visit.

Properly installed a modern combi is very reliable but that is not the issue. Its the performance which is paramount. A storage hot water system performs better and is cheaper for fitting a new boiler when its existing.

Tony

 

[allconfuzed]

I used to say the same as you, but with standard condensing boilers having as many failure parts as combis, I am quite happy to fit a combi now> yes you have no immersion, but how many times do they work anyway after so many years,
I personally go for Viessmann boilers, and have had little trouble with parts, and with the 5 year warranty, it is a better deal for every one, unfortunately they are at the higher end of the market and not for sale in B & Q or screwfix, but you do tend these days to get what you pay for.

 

[Agile]

Last time I compared a Viessmann with a Vaillant it was a little cheaper!

Thats not the point though! a combi is usually inferior in performance to a stored hot water system.

In addition the cost of converting a conventional system to a combi is about £500 more expensive based on our firms charges and in most cases gives no advantages.

The basic and cheapest system is a conventional system if thats whats already installed. A combi is a lower performance system most suited for very small flats where it comes into its own.

In spite of common perception though a combi is just as reliable as a conventional system now.

Tony

 

[heytesto]

Properly installed a modern combi is very reliable but that is not the issue. Its the performance which is paramount. A storage hot water system performs better and is cheaper for fitting a new boiler when its existing.

Tony

I agree with you there in some cases. However, mains pressure around here is generally very good. This equates to great showering from a combi. In the north of the country, nearly all houses have a direct system of cold supply and the higher pressures to support it.

However, I came up from Bournemouth 11 years ago where most properties have indirect cold water supply and poorer supply pressures in some areas.

Stored hot water also has it's benefits. Quicker bath filling etc, but todays showers at 1m head just don't cut it without a pump.

I don't automatically swear by combis, each job must be taken on it's own merits.