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Join Date: Jul 2017
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HVAC New Units

10/17/2017 10:49 AM

Hi there,

I will tell you guys right up front that I have NOT done a lot of research. I will after I get some input from you. I have not done a TAB report in the building yet, for example. It is in the works.

I am looking into replacing two old HVAC units. They are from the 50-60s, and they are a constant volume system. I would like to design the next system as variable air volume. The building has a lot of open areas and currently only two units.

All that said, without having a contractor on site, I would like to get costs for two new nice units, something around 10,000-15,000cfm per unit should do the trick. Maybe I will get three units.

Any thoughts and/or suggestions would be appreciated.

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#1

Re: HVAC new units

10/17/2017 11:26 AM

You want air flow or to cool the building? HVAC is sized on the amount heat they displace not air flow. That is calculated by the size of the rooms. You should be able to find a calculator on line to get you the size of HVAC you need.

https://www.highseer.com/hvac-load-calculator/

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#2

Re: HVAC new units

10/17/2017 12:32 PM

This is something that has to be done on site....Everything has to be taken into account, including building structure...First a heat load must be calculated, then placement, efficiency, ductwork, power availability, type of unit....takes a pro

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#3

Re: HVAC New Units

10/17/2017 1:43 PM

You need professional help on this one. It is by "tonnage", not cfm air flow.

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#4

Re: HVAC New Units

10/19/2017 9:10 AM

"I have NOT done a lot of research"...and when you do you will find your answers!

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