technical question central heating

[purglaspete]

hello my question is we have a pressurised combination gas central heating system that heats 7 double radiators 6 of which have thermostatic valves on , and we have been thinking of getting a wood burning stove for the front room would it be possible to link up a back boiler in the wood burning stove to suppliment the combination boiler so that when we are running the heating system and decide to have the wood burning stove lit it will heat the water going through the combination boiler so making the combination boiler use less gas as the water will be already warmed by the woodburner stove .any help or advice would be greatly appreciated . the wood burner will be on the ground floor and the combination boiler is on the floor above it . the only time the stove will be lit is when the central heating is on so that the pump is circulating the water through the radiators .

[Mike Jackson]

Simple answer is no. You can't run a sealed system from a wood burner because a sealed system needs an overheat thermostat. Complicated answer is you can do it but you need a secondary heat exchanger run on a circuit from the back boiler which also incorporates a heat leak circuit and a means of shutting down the heat to the secondary heat exchager (motorised valve linked via an overheat stat). Cost wise it would be cheaper to rip it all out and start again.

Mike

[stigofthedump]

Hi mike, I for one appreciate the time and effort you put into your reply. Maybe Pete is having technical problems with his PC so I will thank you on his behalf

Vince

[numeniusaqua]

Here is a good article on that subject - it talks about a solar system, but the principle is the same: (click on the text below)
Can I have a solar thermal system if I have a combi-boiler? | YouGen Blog | YouGen, Renewable Energy Made Easy