Question about Plenum size
#1
Question about Plenum size
Hello, I am faced with replacing my air conditioner and furnace. One contractor informed me that my plenum was too small at 8" by 16" and would need to be doubled in size. The other contractor did not even mention it. I will be getting quotes from both next week. Any help about determining if the plenum has to be enlarged or not would be appreciated. It will be a 5 ton AC unit and probably a 175000 to 200000 BTU furnace. Thanks, Bill
#2
Join Date: Aug 2002
Location: Mountain Williams Missouri
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Im just not sure how are what you have there. I will say this. For a 5 ton AC and a 200k furnace no way at all can you do it.
A 8"X16" === 700CfM. your duct there cant take 2 ton AC
It takes about 400 CFM per ton you will need 2000cfm for the 5 ton for a good job you need 350" are a duct about 10"X35".
ED
A 8"X16" === 700CfM. your duct there cant take 2 ton AC
It takes about 400 CFM per ton you will need 2000cfm for the 5 ton for a good job you need 350" are a duct about 10"X35".
ED
#3
Thanks for the reply. Fortunately the plenum can be easily accessed. The idea now is to make it 16" by 16". At least that would be better. The old 4 ton AC unit never did a good job of cooling the house (2 story 3600 sq.ft.). It sounds like the plenum size may have been a big part of the problem. Thanks, Bill Prather
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Hello, I am faced with replacing my air conditioner and furnace. One contractor informed me that my plenum was too small at 8" by 16" and would need to be doubled in size. The other contractor did not even mention it. I will be getting quotes from both next week. Any help about determining if the plenum has to be enlarged or not would be appreciated. It will be a 5 ton AC unit and probably a 175000 to 200000 BTU furnace. Thanks, Bill
thanks