I'd be grateful if anyone could comment on a schematic diagram I've drawn up of my existing 'Gas Gravity fed / pumped CH boiler' (on left of diagram) combined with a future solid fuel back boiler (on Right of diagram).
//www.diynot.com/network/carryoncamping/albums/18674/69910
http://www.flickr.com/photos/44875755@N02/11209804173/
Current set up:
12 kW Gas boiler Gravity fed HW and pumped CH
Dunsley 5kW Wood Burning Stove, (fed on a free supply of wood).
Solar Thermal system heats domestic HW 6 months of the year (not shown on diagram).
Note: Hardly ever use the Gas boiler as our house is VERY well insulated and the 5KW stove does most of the heating. (e.g. gas bill last year <£100)
As part of our home improvements (of which local Building control have been notified) we are toying with the idea of installing a back boiler in the Stove.
It is ONLY 2KW and would be mainly to heat the water in the 200l cylinder during the darker months when the solar thermal is less effective.
I have combined the two systems with a plate heat exchanger. I am aware of the Dunsley Neutraliser but not quite sure how that would be more effective in the current setup?
My thermal calculation for time needed to heat 200 litre HW cylinder from cold by 2kW back boiler (assuming a constant 2kW) are as follows:
Water vol=200litres
Water SHC =4.2 kJ/kgC
DeltaT = (60-10)=50C
Time required for 200 litre cylinder to reach 60C from a cold start would be:
=200*4.2*50/2/3600 hrs
=5.8 hrs
My fire is typically lit for 10-12 hours a day so I have an excess of hot water which could in theory feed the 2 radiators (3400BTU/1KWh) I have/use.
Your time and thoughts are very much appreciated on this topic.
PS
I can email a higher res diagram if anyone is interested.
//www.diynot.com/network/carryoncamping/albums/18674/69910
http://www.flickr.com/photos/44875755@N02/11209804173/
Current set up:
12 kW Gas boiler Gravity fed HW and pumped CH
Dunsley 5kW Wood Burning Stove, (fed on a free supply of wood).
Solar Thermal system heats domestic HW 6 months of the year (not shown on diagram).
Note: Hardly ever use the Gas boiler as our house is VERY well insulated and the 5KW stove does most of the heating. (e.g. gas bill last year <£100)
As part of our home improvements (of which local Building control have been notified) we are toying with the idea of installing a back boiler in the Stove.
It is ONLY 2KW and would be mainly to heat the water in the 200l cylinder during the darker months when the solar thermal is less effective.
I have combined the two systems with a plate heat exchanger. I am aware of the Dunsley Neutraliser but not quite sure how that would be more effective in the current setup?
My thermal calculation for time needed to heat 200 litre HW cylinder from cold by 2kW back boiler (assuming a constant 2kW) are as follows:
Water vol=200litres
Water SHC =4.2 kJ/kgC
DeltaT = (60-10)=50C
Time required for 200 litre cylinder to reach 60C from a cold start would be:
=200*4.2*50/2/3600 hrs
=5.8 hrs
My fire is typically lit for 10-12 hours a day so I have an excess of hot water which could in theory feed the 2 radiators (3400BTU/1KWh) I have/use.
Your time and thoughts are very much appreciated on this topic.
PS
I can email a higher res diagram if anyone is interested.
