Advice wanted on Plumbing in Log Burning Stove & Back Bo

We have bought a log burning stove with a back boiler. My OH has lots of plumbing experience but has never tackled anything like this.

The back boiler has 2 x 28mm feeds (Flow & Return) to the Immersion tank. Having talked to the manufacturer of the stove we need to add on two radiators to avoid the water overheating. Our central heating system is gravity fed.

What we want to know is would it be possible to tap in to our existing heating system, so that any excess hot water will just feed the upstairs radiators. We did think about getting a thermostatic 3 way valve to facilitate this but would like some thoughts as to wether it is feasible??. Also would we need to put a pump on the system??

All comments and thoughs appreciated

My comments and thoughts are that using a wood burner to provide hot water and rads sounds great in principle, but has some problems.

If you lower the temperature in the log burner by connecting other heating loads, you run the risk of incurring significant tar deposits all over the stove, including the glass and the flue. As well as being unsightly, there can be fire risks once this has built up.

Some manufacturers of log burners provide instructions regarding pumps and low temp limit stats, these should be followed.

If you didn't get any such instructions, the manufacturers have chosen to leave it to you, knowing as they will, what is likely to happen. And when it is full of tar, they will say, ah, you are taking too much heat out of the stove........

this is by no means a diy plumbing job i am very well experinced in this field and would recomend that you consult a hetas registered installer

but if you are going to tackle this thing on your own be aware that if not installed properly
people will die

the are very few controls on this type of system and you are relying on the basic princeables of old school heating to make it work

no trv's no pumps' and radiators is a must and should be fitted with lock sheild valves on both flow and return sides also a termostatic and motorised valve must be fitted to the heating side to allow the hot water system to use the heating side as a heat dump

no plastic tanks allowed and no plastic pipe or fittings wot so ever in the system

i hope i have not put you off its a great way of saving money and heating your home and getting water at the same time but in the same way the heat is not instant like gas and it is higher mantinace

oh remember to line the flue you will get better efficency from you stove

best of luck