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Discussion Starter #1
Can you B-vent a furnace or hot water heater through a chimney? If you can I assume the entire flue running from the appliance to the outlet of chimney would also need to be b-vent pipe?
 

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Yes on both accounts, especially if it is a mid efficiency furnace. You can single wall vent the water heater to the B vent but the furnace should have B vent so the flue gas does not cool down B4 it gets to the chimney. They used to allow single wall from the furnace but changed the code to B vent where I am. B vent is ALWAYS better for both appliances as you do not want the flue gases to cool down or condensation or corrosion occurs.
 

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Discussion Starter #3
Yes on both accounts, especially if it is a mid efficiency furnace. You can single wall vent the water heater to the B vent but the furnace should have B vent so the flue gas does not cool down B4 it gets to the chimney. They used to allow single wall from the furnace but changed the code to B vent where I am. B vent is ALWAYS better for both appliances as you do not want the flue gases to cool down or condensation or corrosion occurs.
And with b-venting there is no power vent its all natural draft? Also, what make the double wall b-vent pipe able to keep exhaust gases hotter than single wall?
 

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B vent has 2 layers. 1 inner liner and then a air gap and then a outer liner. Like a thermos bottle the air gap keeps the heat from escaping. Most manufaturers want B vent on mid efficiency units so there is no corrosion problems with the furnace. Has nothing to do with power venting or draft. It is simply a 2 layer vent with an inner and outer liner/sleeve.
 

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Discussion Starter #5
b vent should only be installed vertically though, right? And B vent uses natural draft and no forced draft or induced draft?
 

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Can you B-vent a furnace or hot water heater through a chimney? If you can I assume the entire flue running from the appliance to the outlet of chimney would also need to be b-vent pipe?
Through a chimney, as in you already have a chimney?

If so, you can just line that chimney, and save yourself a lot of money.
 
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