Central Heating - Dual heating sources - separate stove from OFCH

Lewis_Benson

Hi,
I moved into a house recently which has both an oil fired boiler and a solid fuel stove ,Stanley Erin.

You can see from the attached (Crudely drawn) diagram, that the 2 sides are linked by a common flow and return, and T off to their respective coils at each side of the dual coil cylinder.

The system works fairly well, the Oil fire boiler heats the rads and water very well , and the stove does a good job on this also, albeit you need a large fire to keep all 17 rads close to hot,I tend to turn off rads closest to the stove when using it, as there is no need for them, as the stove heats the whole area around it.

The problem with the system, as far as I can see, is that ther is only one NRV on the Oil side of the flow, stopping the stove from heating the oil circuit.
When the Oil boiler is heating the system, its also heating the stove circuit , and both coils, and the rads at the same time, seems a massive waste of fuel to me.

This seems to be a common setup whereby no one know fully how to separate dual systems correctly.

It looks like a fair attempt was made here, but they didn't go the full way , only about 95%.

So what I want to know is , looking at the image attached, can I put an NRV on the stove side of that Flow (I have coloured it in yellow on the diagram), it would not be restricting any gravity feed as would be on the "common" flow between the 2 boiler, and the gravity circuit from the stove would be left fully open, this would simply stop the Oil boiler from heating the stove circuit.

Any feedback and criticism of this idea is fully welcome

Thanks.

Lewis_Benson

Anyone got any input?
Thanks.

Lewis_Benson

Bump
Anyone want to weigh in on this?

Tom44

Stove should have had separate 1” pipes off the other side independently serving copper cylinder and heat dump radiator.

You need on site professional advice, as in, call out a professional plumber to give advice.
Stoves are dangerous if not done right.

That's why there wasn't a rush to answer your question,


By the way,
Your drawing is dangerous, your non return valves and pump valves on stove ( if accidently turned off ) stopes the oil boiler been open vented and been safe.
Basically, regulations are there for a purpose, your plan does not comply.

Sorry

Lewis_Benson

Tom44 wrote: »

Stove should have had separate 1” pipes off the other side independently serving copper cylinder and heat dump radiator.

You need on site professional advice, as in, call out a professional plumber to give advice.
Stoves are dangerous if not done right.

That's why there wasn't a rush to answer your question,


By the way,
Your drawing is dangerous, your non return valves and pump valves on stove ( if accidently turned off ) stopes the oil boiler been open vented and been safe.
Basically, regulations are there for a purpose, your plan does not comply.

Sorry

Thanks for the response.
You are correct, a stove can be a lethal weapon if not plumbed correctly
I've seen the aftermath of a Stanley range where the boiler exploded.

I know what you mean also regarding having separate pipes running independently to the cylender, however I can't do anything about that now without major renovation of the house, as the pipes from the stove are buried behind walls and kitchen cabinets.

Thankfully with the current setup, the.pipes from the stove to the cylinder coil are 1" and there are no valves of any sort on that curcuiit.


Regarding the possible NRV on the stove side of the common flow, you are correct, when I look at it, it closes off the OFCH side of the circuit, so yes, it needs a plumber with experience to look at it and work out the correct and safest way to do it.
I'm not in the position at the moment to go down the route of getting a system link or the likes.

I'll let you know how I get on once a plumber has had a look.

Thanks