We recently moved into a 12 year-old two-story house, and the master bedroom gets uncomfortablly stuffy at night whe we sleep with the door closed. It doesn't matter if we are running the furnace or the A/C. I noticed that the master suite has 4 equal-sized inlets but only a single return register, about the same size as one of the inlet registers. Should the area of the return equal the area of the inlets? Each of the additional smaller bedrooms in the house has a single inlet and single similar-sized return, and they do not get stuffy at night.
Thanks in advance,
R > S
RETURN > Supply ___ Max dP = 0.01"
Originally posted by ivan2002
Should the area of the return equal the area of the inlets?
FL Building Code - Mechanical
601.4 Balanced return air.
Restricted return air occurs in buildings when returns are located in central zones and closed interior doors impede air flow to the return grill or when ceiling spaces are used as return plenums and fire walls restrict air movement from one portion of the return plenum to another.
Provisions shall be made in both residential and commercial buildings to avoid unbalanced air flows and pressure differentials caused by restricted return air.
Pressure differentials across closed doors where returns are centrally located shall be limited to 0.01 inch WC (2.5 pascals) or less.
Pressure differentials across fire walls in ceiling space plenums shall be limited to 0.01 inch WC (2.5 pascals) by providing air duct pathways or air transfer pathways from the high pressure zone to the low zone.
[Edited by dan sw fl on 09-03-2005 at 01:11 PM]
It's Not Rocket Science, But It is SCIENCE
with "Some Art". ___ ___ K EEP I T S IMPLE & S INCERE
Define the Building Envelope and Perform a Detailed Load Calc: It's ALL About Windows and Make-up Air Requirements. Know Your Equipment Capabilities
The amount of return airflow should be +/- 10% of the airflow being supplied into the room.
Just having the proper return grille area does not insure proper return airflow.
Try closing your master bedroom door till there is about a 1/2" gap open.
When your fan is running in the equipment you will probably feel air rushing out due to the lack of return.
When you shut the door off you also limit the amount of air that can be supplied to that room.
Have you set up a Google alert for Carbon Monoxide yet?
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simple answer: yes, you're short on return air.
solution: call in qualified contractor to visibly look at the system and air distribution system to make best possible recommendations, based on YOUR particular system.
Remember, one size DOESN'T fit all.
Everyone has a purpose in life..........even if it's to be a bad example.
Seek first to understand, before seeking to be understood.
if that part of the system is screwed- up, then the rest probably is --
so get or do a load calculation to determine what air is really needed for each room -- program available at this site is excellent -- just measure doors & windows & room size, amount of insulation -- know the orientation of the house with respect to North of the compass.
harvest rainwater,make SHADE,R75/50/30= roof/wall/floor, use HVAC mastic,caulk all wall seams!