Harvesting heat from heating room


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I have two rooms in the basement, one where central heating (burner) is installed and one where people dry their laundry. I am looking for ways to get the unused heat in the room of the burner into the other room to help dry the laundry.
The laws do not allow to make direct connections (that anyhow would be not meaningful as there is a slight smell of fuel).
My idea so far:
  • drill two holes into the wall (15cm diameter)
  • connect a few meters of metal pipe (aluminum) that will be fixed on the ceiling and create a loop
  • add a ventilator that makes air flow through this pipe and harvests the heat
Does anyone have experience?
How much length/pipe surface/etc. is needed to harvest some heat?
Any suggestions, aspects, etc.?
 
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Sounds OK in theory, but unless the burner room is very hot, you won't get much heat being transferred.
You would need to increase the surface area of the exposed type or pipe to get any meaningful gains.
Look at the fins on the back of a fridge.
I'm surprised you can't make holes in wall. How do you get into the rooms?
Is the burner a balanced flue type i.e. does not rely on air entering the room normally through a vent?
Or is it a burner with a stack pipe with air provided by a vent?
When you say laws, are these laws to do with fire prevention, structure or ventilation?
Fire is easily overcome by the use of intumescent sleeves and fire doors. I believe there are fire-safe ventilation fans available.
Some people with wood burners harvest heat from the hot stack.
I'm assuming when you say you can smell fuel it is an oil burner, otherwise if gas, then get out fast.
 
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This sounds funny but if the rooms are next to each other, maybe put a aluminum "window"? it would conduct the heat much faster than anything else, making the two rooms practically thermally coupled (you have no convection, only diffusion, but it would do some of the job I guess)
 
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Sounds OK in theory, but unless the burner room is very hot, you won't get much heat being transferred.
You would need to increase the surface area of the exposed type or pipe to get any meaningful gains.
Look at the fins on the back of a fridge.
I'm surprised you can't make holes in wall. How do you get into the rooms?
Is the burner a balanced flue type i.e. does not rely on air entering the room normally through a vent?
Or is it a burner with a stack pipe with air provided by a vent?
When you say laws, are these laws to do with fire prevention, structure or ventilation?
Fire is easily overcome by the use of intumescent sleeves and fire doors. I believe there are fire-safe ventilation fans available.
Some people with wood burners harvest heat from the hot stack.
I'm assuming when you say you can smell fuel it is an oil burner, otherwise if gas, then get out fast.
It gets I guess up to 30 ° Celsius. Of course, the room has a door and the window is slightly open to let air in. It is an oil burner. My question is how much heat can I transfer with a e.g. 7.5 m pipe 100mm diameter that I install on the ceiling of the burner room plus a fan that moves 100 to 200 cubic meters of air per hour.
 
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I'm still interested by what laws you refer to.
I doubt that 30 degrees will give you any worthwhile gains and the expense of aluminium tube etc. will outweigh the cost of any heat gains.
The calculations to work out the heat transfer, if any, are too complex for this forum. The only thing that might be effective is increase the surface area of the collector and paint it matt black.
It's worrying that you rely on doors and windows being left open to provide air to combustion air. UK laws would not allow that and you would have to fit a properly sized vent to outside air.
What might be worth looking at is how commercial heat recovery units work. Domestic units are available from Xpelair for example
 
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I'm still interested by what laws you refer to.
I doubt that 30 degrees will give you any worthwhile gains and the expense of aluminium tube etc. will outweigh the cost of any heat gains.
The calculations to work out the heat transfer, if any, are too complex for this forum. The only thing that might be effective is increase the surface area of the collector and paint it matt black.
It's worrying that you rely on doors and windows being left open to provide air to combustion air. UK laws would not allow that and you would have to fit a properly sized vent to outside air.
What might be worth looking at is how commercial heat recovery units work. Domestic units are available from Xpelair for example
... if you read German. ;)
 

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