TL/DR version: 1 hvac register in 280 sqft room (too cold), but 2 or 3 in 110 sqft room (too hot), builder says this is not a problem?

Hello everyone,

I'm having some heating distribution problems in my house. The master bedroom at the north (back) side of the house is much colder than the rest of the house, and a smaller bedroom in the south (front facing) side of the house is way too hot. Would I be right to think it's because the placement/distribution of the hvac registers?

Some information:

Cold master bedroom: I have a 280 sqft bedroom that has ONE SINGLE hvac register near the window that is on the back side of the house. A return vent is found at the opposite end of the room. One register in the en suite bath (about 100 sqft), and one more in the walk in closet (about 40 sqft). When I open the door to this bedroom and go into the hallway, I can clearly feel the difference in temperature. This room is the furthest from the HVAC unit in the basement.

Over heated bedroom: This is a 110 sqft bedroom, it has 2 in the room. There is one more more in the walk-in closet (about 30 sqft) and one more in the en suite bath (about 60 sqft). Return vent near the door of the bedroom.

If I set the thermostat so the master bedroom is warm enough, the whole house feels too warm and the over heated bedroom is impossible to sleep in because I'll wake up in sweat. If I set it so the rest of the house feels right, the master bedroom is way too cold, and the over heated bedroom is still warmer than the rest.

I reported this issue to the builder last winter but they said the hvac layout is designed by professionals and it's "fine" for a room to be a little colder than the rest.

Whaaaaat dooooo I doooo..Please advice!

 

Welcome to the forums.

I would agree that one register in that large of a room is inadequate.

Can anything be done about the ductwork now ?
In other words..... does it run thru an attic or basement where it could be changed ?

If not..... the only thing you can do is to close the registers slightly in the hot rooms
to force more heated air to the colder room.

 

Hi Pete, thanks for your comments!
I tried closing off the registers in the hot room. It's a slight improvement for the hot room, but didn't help the cold room at all.
I believe it would be hard to add another register to the cold room because it's on the second floor and the furnace is in the basement, it would be a looot of work right?
The ducts are visible in the unfinished basement though. I just heard that I can try adding some kind of a air pump to the duct work that sucks/forces more hot air into that one register, I guess this will be the easiest solution. Does anyone know anything about this?

 

Those booster fans don't really do much.

I'd look around the ductwork in the basement for any type of damper. It would look like a handle on the bottom or the side of the duct. If found..... they mmay be able to be changed. Let us know if you spot any.

 

Where are the rooms in relation to the furnace, including floors?

If large room is upstairs, furthest away then air flow is going to be the least vs if the small room is right next to furnace.

 

All the rooms I mentioned are on the second floor. The first floor is fine.
And yes the hot room is a lot closer to the actual furnace unit in the basement, and the cold room is the farthest.

 

Did you locate any duct dampers ?
Mine has one for the first floor and the second floor.

 

Hi Pete, I did find the dampers, but looking at the handles it's not obvious if they are on the open or closed position. Guess I'll have to just go by trial-and-error. Thanks for the tips!
The cold room register does have a strong air flow, it's just that the air coming out is not nearly as hot as the hot room. I guess adjusting the dampers won't directly solve the cold problem?

 

You can get a CFM meter and do some more exact measurements to help balance the system now that you've located the dampers. It should give you CFM from each register and the temperature of the air coming out.

 

run a heat load on the second floor rooms
This will tell you what you need. If different bill the builder for the cost and have him fix it.

 

The handle is the same as the damper door, across the duct it's closed, same direction as duct it's open.

You have atypical situation that effects 99% of two story homes.

What is frustrating is that for a few hundred dollars when the system was installed a zone system could have been installed to resolve!

But builders cut corners and this is one!