New boiler needed for 1 pipe system

[mat167]

Hi Everyone,

I have just moved into a 1950's house and have a traditional boiler with a tank in the bathroom and a 1 pipe central heating system.

I want to replace the boiler with a Combi to remove the tank. do I need a complete new system or can I hook the Combi up to the existing 1 pipe system?

I am also planning to extend the house in the future, can I therefore add on to the existing 1 pipe system?

Matt

 

[Dan Robinson]

Most boilers will work, but the Intergas is able to be fitted on an open vented heating system.

 

[ServiceNumpty]

If you're looking to add onto the system at a later date then I would advise you to get rid of the 1 pipe system and install a complete new system with isolated 22mm flow and return spurs to where the extension might be in the future.
Just make sure you get a decent installer.

 

[dcawkwell]

Put a 2 pipe system in. Shouldn't take too long. Half the piping is there.

 

[ajsdoc]

I've just had some plumbers finish this very job (one pipe to two pipe). I managed to have a new boiler fitted to a one pipe system a few months ago, original installer didn't realise it was one pipe...

Anyway, I had floors up as I'm planning having a wood floor down then realised it was a one pipe system Was uncertain whether to do it or not (it's a bit of work and ££), but seemed opportune. Quite a bit of work in terms of moving stuff about to allow them to repipe, but I have to say less mess and upheaval than I imagined

Rads much hotter, TRVs now work (they didn't really before) and I feel happier putting a new floor over it all now.

I'm not sure all the claims about the efficiency of modern condensors bear any truth if you are fitting one to a one pipe system.

 

[mat167]

Thanks you all for the info

ajsdoc how many bedrooms do you have and what was the approx cost inc new boiler?

 

[Agile]

I'm not sure all the claims about the efficiency of modern condensors bear any truth if you are fitting one to a one pipe system.

A condensing boiler can be very efficient indeed on a one pipe system.

But the problem is that the optimum flow temperature is 75 C and with a differential of 15 C that makes the return at 60 C which will be about the temperature of the last radiator.

So the average rad temp is lower.

I solve that problem economically by fitting a high output radiator centrally in the house so that it provides much of the heat output required. Also being connected in parallel it increases the flow through the boiler which is usually marginal on most one pipe systems on their own.

Tony Glazier