Overheat protection for a wood burner with back boiler install?

[njones]

Hey guys,

I've searched the forum, but haven't found anything useful. I don't know the name of the thing I'm looking for, so I apologize in advance if this is something basic that I should have found in a search.

So basically, my electrician is an old fella who doesn't know much about heating controls (I live in the sticks - he's the only one I can get) and while he has gotten my heat pump and zoned heating all wired up, the one thing he's not been able to figure out is some kind of overheat protection for when the wood burning stove is lit.

Basically, I want something that if the temperature in the pipes gets too high, will automatically open all 4 radiator zones and dump the heat safely, so there is no risk of water in the stove boiling.

The only idea he's come up with so far involves 4 pipe stats which would work, but it'd look stupid. I'm convinced that there must be a unit specifically made for this.

Can anyone point me in the right direction please - a link to a product I can show to my electrician?

I greatly appreciate your help!

 

[Ric2013]

I realise you're in Ireland. In the UK, regulations insist on a gravity circulation failsafe, but Ireland may be less strict?

I can't see how you'd need 4 pipe stats to open four zone valves. I'm assuming this is because he can't run them in parallel and still be able to have zone control during normal operation. Why not use relays and a single pipe stat?

In fairness to your sparky, four pipe stats means all four would have to fail to render the system inoperative. But bear in mind that in the event of a power cut you still have no backup. Have you got a contingency plan for that?

 

[njones]

There is a gravity circulation failsafe, and in the event of a power outage the fire would be doused before that could be saturated.

The failsafe I want is more for everyday use... When the power is still on.

The stove is huge, 30kw, designed originally to heat the entire house before we got a heat pump. The risk is more that if there is an average size fire burning, but thermostats have 3 of the 4 zones closed, then it could potentially overheat without us realising until it's too late. Currently I'm only lighting the fire when I know I'll be home for a few hours, and I'm manually keeping an eye on the temps displayed on the controller screen for the heat pump... If it passes 75c I switch on all the zones to let the temp drop.

 

[Ric2013]

I see where you are coming from. I'm not aware of a specific product except what I have already suggested. I would suggest if no one else on this forum can help, then the Navitron forum would have the information (as I'm not aware of any solid-fuel specific members on plumbersforums). Except the Navitron forum has now shut down and, in any case, it took me 5 years to get allowed access to the forum in the first place because they wouldn't let you sign up with a Yahoo email account. You may find useful information on something like the Green Building Forum or similar.

If you come across the specific product you are after, I'm always interested!

 

[ShaunCorbs]

No 2 port valves controlled by a stat ?