Good stuff! Thanks for the info
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I think this is often the source of the confusion. I have always wondered though, how does a fan assisted appliance not produce at least some amount of positive pressure in the flue, assuming the fan is installed at the appliance? Is it just that the amount of pressure is so low it doesn’t count?
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I’m not sure if it so much about positive pressure as much as it is the temp of the exhaust.
Gravity furnace typically needs no assist, 80 percent needs some, 90 percent needs more etc.
Cooler air will not exhaust well. Hot water heater exhaust colliding with cooler exhaust won’t go anywhere
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Ryan Brian‘s got your answer. Fan assisted category one appliances are just slightly more efficient than a natural draft category one appliance. Less heat is created and the fan assists just helps produce I draw.
Obviously B vents are not airtight and therefore cannot accept any appliance that creates a positive pressure. A fan assisted category one appliance does not meet that criteria.
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Category 1 fans are called ‘draft inducers’. The purpose is to create a negative pressure inside the heat exchanger and purge any remaining combustion gasses.
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Yes…
Inadequate amount of flue fasteners.
The minimum 1/4" per foot slope appears surpassed.
No adverse conditions observed the day of the inspection.
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Yes and it also stays on to create a constant source of oxygen for the burners.
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That is a good way to think about it I guess. Helps clarify the difference between power vented and induced draft.
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Haha just checking.
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Thanks a lot for all the information everyone! I’ve learned a ton. Always changing the ways I can inspect better.
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Great attitude!!! The learning never stops.
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I can see where I had a ton of confusion. Not that I gave my clients terrible information as I just wanted to improve what was going on, but, still, annoyed at my confusion. Thanks for the chat!
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