Linking solid fuel stove to central heating

[Tank]

Gents,
Your advice and experience would be greatly appreciated by this keen amateur. I want to put a wood burner with a back boiler onto the outside wall of a single story extension and then link it into the current vented gas central heating system of the rest of the house. I believe in principle this is possible however my concern is, if the back boiler is linked to the central heating and is reliant on the central heating pump, if the pump fails then presumably the back boiler would become a pressure cooker ready to blow! So for safety reasons I understand the back boiler should be fitted so that it thermo-syphons, but as I can't run the pipes from the back boiler vertically (as the extension is single story) I will have to run them about 10m horizontally before they can go vertically, will this work and is it safe?
Thanks in advance for all and any comments.
Regards
Nick

 

[Billy Bob Bob]

sorry mate,even though i have done a few of these this is not a diy job so will not advise you on how to do it,anyway solid fuel you need to be heatas registered,and you will kill yourself if it gos wrong in some respects there's more to solid fuel than gas

 

[Tank]

Mark,
Many thanks for your reply, I have no intention of fitting the stove or linking it to the central heating but I was just wanting to know if it can be done and done safely, as I don't want a local pumber saying it can be done when he really doesn't know and I then have problems later.
Thanks
Nick

 

[Billy Bob Bob]

yes it can be done,you will need a twincoil cylinder,non return valves,second pump(if running ch) and a steel or copper expansion tank as a starter for ten ,it can be done safely,if your plumber has the knowledge,but be warned they dont work that well and the wood you use needs to be a specific type to get the best out of it, on the flue side of things(the woodburner) it will get expensive

 

[Tank]

Mark,
Many thanks for the good news. Can I ask just one more question, what if there is a power cut and the pumps stop, will the back boiler water continue to circulate thermally even with such a long vertical run from the back boiler?
Thanks
Nick

 

[Billy Bob Bob]

not on the heating,but it will to hotwater because thats gravity anyway,it could vent over in to the tank thats why it must be metal

 

[justlead1]

Hi Gravity circulation is driven by the difference in the wieght between hot water and cooler water. This diference is measured in parts of an inch or mm. and it is that which creates the circulation. When long horizontal runs are used the extra frictional resistance reduces the circulating pressure and the circulation is impeded. When circulation is very slow the boiler will heat the water quicker than it can circulate, causing a build up of heat at the boiler, resulting in boiling, which will then discharge steam via the flow/vent into the cistern that is feeding the system. This situation should not allowed to happen, it is dangerous, noisy and frightening. As well as being a danger to persons in the property, it can have serious effect on the structure of the building, caused by the condensing of steam in the roof space. Resulting in ceilings, electrics and roof timbers getting wet. Good Luck