combi boiler on a single pipe system.

Is it possible to fit a combi boiler to a single pipe heating system?

 

Yes but your plumber will need to know what he's doing and performance won't be amazing but it probably isn't now
Is there no scope to repipe to a flow and return system?

 

I have just done one Yes not ideal but it does work .

 

Ok so it can be done and then at a later date the system can be changed to a two pipe system flow and return. A the moment the disruption would be so big running a dual pipe system Iwanted to know if the boiler packed up could it be done. the boiler at the moment is an Ideal standard Hide away. It has been Fantastic so far but I know it is getting old. It has been moved twice and the gravity hot water is a bit temprimental because of its latest position.

 

yep the manufacturers dont like it , but they can not demand the system is changed .
The one I have just done is getting altered to a Two pipe . one day

 

Yes it can be done but unless the old boiler isn't working why would you. A one pipe system is only 70% efficient. So there would be no benifit. From memory only Vaillant allow thete boilers to be fitted to a one pipe system.

 

You could always fit a low loss header, or a plate heat exchanger and leave the old system as open vent but just the boiler as sealed, seen this done on a larger system in a care home

 

Done one on an oil combia few years back. Not brilliant but works

 

Where did you get that from; and how do you measure efficiency?

 

From Vaillant a few years ago now, a customer wanted to keep the one pipe system, I wouldn't do the job but a few years later i did a service on the boiler, she complained that the gas bills hadn't come down at all

 

One pipe systems are still used on commercial installations, where every penny counts. I can't see finance directors being very happy with systems which are only 70% efficient.

Most of the heat output of a boiler is used to heat the house - apart from a small amount lost from pipes in unheated parts, e.g under the floor. So if 5% is lost there is still 95% left to heat the house. The boiler may be only 70% efficient - or less if it's very old - but that has nothing to do with the piping system.

 

Fitted a WB combi to one 5 years ago and it's worked great. Just balance the system well and it should be fine. Use full flow trv's if needed.

 

Just an update.
I have had a combi fitted to the one pipe system. It works very well. It always did with the old boiler. The one thing I miss with the combi is the warm airing cupboard but I will get used to it