Buffalobillpatrick
Member
http://www.viessmann-us.com/content/dam/internet-ca/pdfs/tanks/vitocell-b_100_tdm.pdf
It's a 79 gal Indirect DHW tank with 2 internal coil Heat Exchangers (HX)
Planning my next house heating system. (I like buffer tanks)
Zone 5 high altitude, 3 in-slab zones: 15Kbtu/h , 8K, & 8K
Indirect will be tank heated via bottom coil HX with a 30* delta aquastat control.
3 heat sources: Solar, Heat Pump, NG Burnham RV3 (already own), computer selected automatically, based on fuel cost & solar tank temp. etc.
Buffer Tank math:
t = (vbt*500*dt) / (qh - qload)
t = runtime in minutes
vbt = vol buffer gal
dt = buffer dt
qh = boiler output BTU/hr
qload = emitter output BTU/hr
Burnham says to derate by 18% for 9,000' altitude. 48,000 DOE x .82 = 39,360 btu/h
About 30 minute burn time, without system or DHW draw
Top coil HX will be used to pull heat out of tank for system heating: 3 zone valves + Grundfos Alpha pump.
much like this diagram:
http://www.houseneeds.com/learning-...kless-heat-combo-with-indirect-storage-tank-5
Comments ?
It's a 79 gal Indirect DHW tank with 2 internal coil Heat Exchangers (HX)
Planning my next house heating system. (I like buffer tanks)
Zone 5 high altitude, 3 in-slab zones: 15Kbtu/h , 8K, & 8K
Indirect will be tank heated via bottom coil HX with a 30* delta aquastat control.
3 heat sources: Solar, Heat Pump, NG Burnham RV3 (already own), computer selected automatically, based on fuel cost & solar tank temp. etc.
Buffer Tank math:
t = (vbt*500*dt) / (qh - qload)
t = runtime in minutes
vbt = vol buffer gal
dt = buffer dt
qh = boiler output BTU/hr
qload = emitter output BTU/hr
Burnham says to derate by 18% for 9,000' altitude. 48,000 DOE x .82 = 39,360 btu/h
About 30 minute burn time, without system or DHW draw
Top coil HX will be used to pull heat out of tank for system heating: 3 zone valves + Grundfos Alpha pump.
much like this diagram:
http://www.houseneeds.com/learning-...kless-heat-combo-with-indirect-storage-tank-5
Comments ?
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