HVAC experts need some help. - Contractor Talk - Professional Construction and Remodeling Forum

mact60 · 06-04-2009, 11:09 PM

Bought a 2 story which has a single unit heat and air. In summer downstairs is comfortable while upstairs is hot. In the winter it's when it's comfortable downstairs it's hot upstairs. My thermostat is downstairs. Whats the solution to making the upstairs comfortable?

mdshunk · 06-04-2009, 11:12 PM

There is no solution other than the redesign the duct system. Improper duct design is the one and only cause for your issue. You can band-aid it a bit by dampering down the downstairs supplies to force more upstairs. This has it's limitations also, since you stand a chance of freezing the coil in the summer or shutting down on high limit in the winter. Also, keep the upstairs room doors open if you don't have a return in each room. You can try leaving the fan on "ON" instead of "Auto" to constantly stir the air in the whole house and even things out a bit. That might bug you though, but it often helps some.

flashheatingand · 06-04-2009, 11:49 PM

Depends on how much you are willing to spend. You could install another hvac system in the attic for the second floor or you could invest in a control setup with zone dampers. Your problem is common. There are several possible solutions. Obviously, not knowing the layout of your home, or your budget this is just a quick suggestion. But, I would bet a zone controler setup would be the best bang for the buck.

westernhvac · 06-05-2009, 07:36 AM

get a zone system installed. Try to get one that has modulating dampers that are controlled in conjunction with a leaving air temperature sensor. If both of your zones are approximately the same size then it will work well for you. If your upstairs zone is a lot smaller, you might need an auxilliary unit upstairs.

NickTech · 06-05-2009, 10:02 AM

there are too many variables to determine the fix. but attic insulation and ventalation in the summer can decrease the temperature of the surface area of your ceiling a great deal relieving some of the load. the winter problem is most likely hot air rising to the upstairs as well as the warm being drawn there by the return (assuming the return is upthere). splitting the return, or completely rerouting it the the 1st flr could alleviate that.

Remco Air · 06-05-2009, 04:04 PM

Install a second unit upstairs or zoning system. Common problem I tend to find all the time.