Home & Garden

Air conditioning not cooling certain rooms upstairs

  • Last Updated:
  • Jun 30th, 2010 11:19 am
Tags:
None
[OP]
Newbie
User avatar
Nov 24, 2007
39 posts
89 upvotes

Air conditioning not cooling certain rooms upstairs

We have a 3 storey house (basement, main floor and bedrooms upstairs). In the summer when we have the air conditioning on, the basement is freezing. We stuff old bedsheets into the vents. The main floor is the perfect temperature but the 2 bedrooms located in the back of the house is always warmer than the other bedrooms. The master bedroom which is located in the front of the house is the largest room but it has 2 vents and is always the coolest room out of all the bedrooms. Why are the other bedrooms warmer and how do we remedy this problem without spending a whole load of money?
11 replies
Deal Guru
Dec 10, 2004
11002 posts
868 upvotes
Kanata
Do you feel the cool air from the vents in those 2 rooms when the AC is on? how is the pressure/flow? Are the air return vents blocked in those rooms? Are they south facing?
Sr. Member
Jun 13, 2010
949 posts
48 upvotes
I'm guessing the 2 bedrooms have a lot sun exposure during the day? You probably need better blinds or curtains to block out the sun.
Deal Expert
User avatar
May 10, 2005
24879 posts
2466 upvotes
Ottawa
The real simple answer is to shut off the airflow to the basement. Cold air falls so the air from upstairs will get downstairs. Secondly, partially open the mid level dampers/vents and fully open the upper level dampers/vents.
Make sure there are no blockages, ensure your filter is clean. Leave the furnace fan running all the time.
This is called "balancing" your HVAC or ducts or vents. Google "balancing your ducts" and get tons of hits.
Fixing this will not immediately produce results. It takes a few days and up to a week to feel any change in airflow throughout the house so, you need to wat between adjustments.
Lastly, perhaps you have a furnace motor that is too weak to push cold air? Cold air is much heavier than warm air and some motors just do not have enough push to get it flowing properly. A visit from your favorite HVAC guy can determine that.
[OP]
Newbie
User avatar
Nov 24, 2007
39 posts
89 upvotes
goofball wrote:
Jun 23rd, 2010 10:21 pm
Do you feel the cool air from the vents in those 2 rooms when the AC is on? how is the pressure/flow? Are the air return vents blocked in those rooms? Are they south facing?
Yes we feel the cool air coming out of the vent but it does not seem to be cooling as efficiently as in the other bedrooms. There is no blockage and we have the dampers/vents fully opened. We're going to try Pete_Coach's suggestion of partially opening the dampers/vents on the main floor and having the top floor dampers fully opened. Since the master bedroom is always cooler I'm also going to partially closed those damps in the hopes of balancing the air flow. We leave the blinds closed so that should not be an issue. Thank you for the suggestions. Let's see if we notice any difference.
Member
User avatar
Jan 18, 2003
294 posts
3 upvotes
I'd suggest keeping the bedroom doors closed as much as possbile. If all else fails get a few of these, http://www.atrendyhome.com/durebofan.html we have them in 2 of our bedrooms and they work wonders. Home Depot sells one called I think the Cyclone, but Home Hardware carries a different brand that seems to work better.
[OP]
Newbie
User avatar
Nov 24, 2007
39 posts
89 upvotes
Problem fixed! Thank you for your help. Really appreciate it.
Deal Addict
Aug 13, 2008
2870 posts
203 upvotes
Mississauga
problem fixed?

was it something else? or did you use one of these suggestions?

if so, which one? i'd like to know since im having the same problem.
[OP]
Newbie
User avatar
Nov 24, 2007
39 posts
89 upvotes
mbk.2k3 wrote:
Jun 25th, 2010 11:10 pm
problem fixed?

was it something else? or did you use one of these suggestions?

if so, which one? i'd like to know since im having the same problem.
It was such an easy fix but I never thought about "balancing the air" by controlling the dampers and vents. Since the basement is always very cold, we stuffed the vents with old bedsheets etc. Then we closed off the dampers and vents in the rooms we rarely stay in. We also cleaned the air intakes (it was very dirty). By just closing some of the dampers and vents, these 2 rooms saw a remarkable drop in temperature.
Newbie
Feb 2, 2007
82 posts
6 upvotes
I have the same problem. How do you get acess to the dampers that feed the second floor vents? Are all the damper controls located in the basement somewhere?
Deal Expert
User avatar
May 10, 2005
24879 posts
2466 upvotes
Ottawa
timezwasting wrote:
Jun 28th, 2010 5:55 pm
I have the same problem. How do you get acess to the dampers that feed the second floor vents? Are all the damper controls located in the basement somewhere?
There are normally dampers on each duct line to each room coming from the furnace. Yes, in the basement and fairly close to the furnace. Having said that, I have heard that in newer houses they do not put them in anymore but I cannot verify that.
If you have finished your basement, you may have covered up the access to the dampers.
http://oee.nrcan.gc.ca/residential/pers ... cfm?attr=4
[OP]
Newbie
User avatar
Nov 24, 2007
39 posts
89 upvotes
timezwasting wrote:
Jun 28th, 2010 5:55 pm
I have the same problem. How do you get acess to the dampers that feed the second floor vents? Are all the damper controls located in the basement somewhere?
Our house is about 13 years old. We gave our air intakes a thorough vacuuming. It was filthy as the dust collects inside the walls. We have 2 on the main floor and 2 on the top floor. To gain access to the dampers, remove the vent covers located on the floor and reach below where the air duct opening is located. There should be a round flap which you can open and close to control the air flow. In our master bedroom where it is the coolest because we have 2 vents, we kept one vent opened and the other one shut. It will take some experimenting to see what works best but after we shut off a few of the dampers on the main floor, the 2 rooms in the back felt so much more comfortable. Good luck!
× < >

Top