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Bobrien
New Addition, HVAC Question

We recently added 1007 sq ft to our home. Our heater and air conditioning unit should be able to provide full coverage to the new addition according to our HVAC contractor.

We still have the same heating and cooling in the house, but where it opens to the new addition, which is a kitchen/dinning/great room, the air flow is minimal. I know the contractor used larger duct work, and added 6 new registers off the HVAC unit. The addition is very close to the HVAC unit. Unfortunately I have not been able to reach our contractor to answer some of my questions.

My question is, can something like an in-line blower or fan be installed in the new ductwork to boost the air-flow?

hvhehcca
Re: New Addition, HVAC Question

You cannot add a booster. How did your contractor come up with that your existing system would work when you added roughly 20,000 btu's to heat and more than that to cool depending on what part of the country you are in? Did he provide you with a Manual J heat loss/heat gain? Sounds as though the blower cannot move the CFM that is needed. One reason could be it is not big enough.

I would sent him a registered letter describing your issues and ask for the heat loss/heat gain that he did of the home to come up with his thought process that the unit is big enough. A heat loss/heat gain is a industry standard. If he didn't do it you have legal recourse to solve your problem.

If it's an undersized unit and improper duct sizing that could be a real costly fix. You have to give him the opportunity to fix it. I would use this as a guideline to making sure it is fixed correctly.

https://www.acca.org/industry/ansi-standards

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