Boiler stove with low output to room

[Joe 90]

Another thread got me thinking on our stove again. Its hard to find any information but has anyone got a boiler stove with a low output to the room for new and well insulated houses. My current stove is supposed to be putting out 4kw to room and 16kw to radiators but its far too much. Its probably putting very little to the radiators coz I can't fuel it up properly.
Something like a woodfire cx12. Its supposed to be putting 2.2kw to room.

 

[Kayos]

A 20kw stove must be huge, most gas boilers are massively over sized. Average heat load in the UK is 6 to 8kw (not counting instant hot water from a combi, thats different)

 

[julianf]

I had, and sold, a woodwarm 20k fireview, with the whole compliment of boilers. I think that was supposed to do 3 to the room and 17 to the water.

The only bits that were not jacketed on it were the glass and the base.

 

[waddycall]

You’d need something with a solid door. Not very common these days.

 

[willie.macleod]

Another thread got me thinking on our stove again. Its hard to find any information but has anyone got a boiler stove with a low output to the room for new and well insulated houses. My current stove is supposed to be putting out 4kw to room and 16kw to radiators but its far too much. Its probably putting very little to the radiators coz I can't fuel it up properly.
Something like a woodfire cx12. Its supposed to be putting 2.2kw to room.

I've got Dunsley Highlander 10CH in a very well insulated new build and it works well. I use a Laddomat loading valve, it has a huge header tank and a massive amount of heat storage capacity with 150mm thickness of concrete/screed with 7 underfloor heating zones as well as 300L of hot water tank to heat. The house itself is very open plan which helps with the heated air transfer, plus it has MVHR to help move air around. The stove itself takes external air for combustion. I spent a reasonable amount of time researching, purchasing and installing everything so I can avoid having oil or gas tankers here, no other boilers. We have enough fuel locally in the form of waste timber and peat.

For yourself I would look to keep your stove and look more at how you can effectively load your back boiler and get the heat away from it to your radiators throughout the house. Is it a pumped system, are all the radiators warming in a sensible fashion, how does this tie in with any other heating system etc.

 

[Joe 90]

A 20kw stove must be huge, most gas boilers are massively over sized. Average heat load in the UK is 6 to 8kw (not counting instant hot water from a combi, thats different)

Its a boru carraig mor 20kw. Thats the smallest in that range. It heats 14 single radiators, 16kw to radiators 4kw to room.

 

[Joe 90]

I've got Dunsley Highlander 10CH in a very well insulated new build and it works well. I use a Laddomat loading valve, it has a huge header tank and a massive amount of heat storage capacity with 150mm thickness of concrete/screed with 7 underfloor heating zones as well as 300L of hot water tank to heat. The house itself is very open plan which helps with the heated air transfer, plus it has MVHR to help move air around. The stove itself takes external air for combustion. I spent a reasonable amount of time researching, purchasing and installing everything so I can avoid having oil or gas tankers here, no other boilers. We have enough fuel locally in the form of waste timber and peat.

For yourself I would look to keep your stove and look more at how you can effectively load your back boiler and get the heat away from it to your radiators throughout the house. Is it a pumped system, are all the radiators warming in a sensible fashion, how does this tie in with any other heating system etc.

Yours is higher output to the room than mine. I think yours is 5.2kw to the room. Mine also has direct air feed.
With a normal fire on it will easily heat all radiators. It is pumped. It first worked on gravity to a thermal store and then when the store was supposed to get to temperature it would then be pumped to radiators but as I could only get a really small fire on, it was taking ages to heat the thermal store and the rest of the house freezing and living room to warm. So I changed it that all heat went to radiators pumped, if the electric goes out it then goes back to gravity to the store.
But still problem of living room way to warm even with windows open.

 

[Joe 90]

Radiator is also switched off in same room.
Oil heating doesn't go on then as temp is high.
Fan on top of stove made very little difference pointed towards the door.

 

[willie.macleod]

What is it you are looking for in a stove? If you have an oil boiler as your primary fuel source to charge your thermal store and this is a secondary heat source then can you use something like the slower burning briquettes - you certainly won't be needing to open any windows with some of them! Must be a happy medium to be found.

 

[Joe 90]

I've never tried briquettes but that sounds like its back to a very small fire not heating the rest of the house.
Yes the oil is the main heat but during very cold spells its nice to light a fire or stove but it doesn't make sense to be running oil and and a stove. A proper spec stove should easily cope with it on its own.
The newest stoves is now trying to get the heat to the water rather than the room as houses are now to well insulated for the room its in.
And I'm thinking that would suit me but don't know enough about it to throw more money at it.
When I bought my stove 4kw to room was lowest I could find but I think some go down now to 2.2kw.

 

[willie.macleod]

As far as I can see the house isn't designed for the heating system you want and probably no easy way around it. I think changing to a 2.2Kw room output stove will do very little - with the stove in a well insulated room all that will happen is that it will take a few minutes longer to get to the stage you have to open windows. The heat loss of the room is too low for the heat source, the room too small and no significant air transfer of heat if we are only talking about a single doorway. Every internal door in my house opens onto the open plan space where the stove is.

The cheap and easy way to see if a 2.2Kw stove is going to overheat the room to the same degree is to leave the stove off, get a £10 2Kw electric heater, turn the thermostat up as high as it will go and leave it on for a significant period of time. If it gets up to its max temp within a short period of time and the thermostat kicks in and won't switch back on quickly then you 2Kw stove isn't likely to work.