Can I disconnect air return.


  #1  
Old 03-15-04, 03:30 AM
Rapid
Visiting Guest
Posts: n/a
Can I disconnect air return.

I have a gas, forced air furnace/aircon. I have two air return ducts upstairs, one in the master bedroom, one on the landing.

These returns come down into the basement and go under an I beam, screwing up my headroom. Moving more than a foot or two won't work, so I'm wondering if they can be disconnected or bypassed in some fashion.

I'm aware that when these systems are planned/installed they are balanced, but I'm wondering is disconnecting one or both returns something I can pursue?

It would give me an extra 10'x12' if I could get them out of there, that's why I'd like to get rid of them.

Thanks
 
  #2  
Old 03-15-04, 05:44 AM
Ed Imeduc's Avatar
Member
Join Date: Aug 2002
Location: Mountain Williams Missouri
Posts: 18,386
Received 0 Votes on 0 Posts
Lot of can I here. Yes you can but where will you get the return air for the furnace to replace them. Also how will you get return air out of the rooms if you cut it off down in the basement.
I think for sure you need both of them for the heat and cool to work right in your home ED
 
  #3  
Old 03-15-04, 03:44 PM
Rapid
Visiting Guest
Posts: n/a
I can put a new air return in the basement and another on the ground floor. This will leave me with none upstairs.

If I find that it's too hot upstairs in the summer, I was thinking about an extractor fan in the ceiling on the upstairs landing. I've seen some built into light fitures that vent to the attic.

Any thoughts on the extractor fan idea?
 
  #4  
Old 03-15-04, 04:58 PM
Ed Imeduc's Avatar
Member
Join Date: Aug 2002
Location: Mountain Williams Missouri
Posts: 18,386
Received 0 Votes on 0 Posts
If I find that it's too hot upstairs in the summer, I was thinking about an extractor fan in the ceiling on the upstairs landing. I've seen some built into light fitures that vent to the attic.
No way. First where are how would the fan get its air to blow out in the attic?

Then if it did get air it would be hot and with a high humidity. that the A/C is working on the get the humidity out of the home.

You need that return upstairs for both on heat and for the AC.
Dont cut down on the sq" of cold air return you have now.

Some have put a fan over the stairs to blow up and down to try and help. if it works I dont know and cant say.
ED
 
  #5  
Old 03-15-04, 05:27 PM
Sharp Advice's Avatar
Admin Emeritus
Join Date: Feb 1998
Location: The Shake and Bake State USA
Posts: 10,398
Received 5 Votes on 4 Posts
Hello: Rapid

For your own safety and proper operation of the furnace, you cannot put the return in the basement where the heater is. Very dangerous thing to do and here is why.

When the fan turns on, a negetive air pressure, partial vacuum, will develope in the basement. When that happens, it will draw fumes from inside the firebox and any open downdraft diverters.

The divertor is likely on the furnace at the base of the vent discharge from the firbox chambers. The partial vacuum will draw the fumes into the intake and circulate them into the living space.

Carbon monixide poisonings happen this way. Use caution. Even having fresh air vents or opend windows etc etc cannot over come the draw of the blower fan. Danger will always be present.

Also violates local installtion codes and voids homeowner policies since the work was not done to code. Get professional help and advice from local heating contractor and or installers.
 
  #6  
Old 03-16-04, 05:52 AM
Rapid
Visiting Guest
Posts: n/a
Originally posted by Sharp Advice
Hello: Rapid

For your own safety and proper operation of the furnace, you cannot put the return in the basement where the heater is. Very dangerous thing to do and here is why.
Right now the air return duct is open to the basement, about 2' x 6" opening at the basment ceiling. About 6' away from the heater. There is a plate to restrict airflow in, but it's in the open postion. Is this a problem?

House is 4 years old.
 
  #7  
Old 03-16-04, 06:04 AM
Sharp Advice's Avatar
Admin Emeritus
Join Date: Feb 1998
Location: The Shake and Bake State USA
Posts: 10,398
Received 5 Votes on 4 Posts
Rapid

If the air return is in the unheated basement, why I will never understand. Does not make sense to heat cold air and blow it into the house where there is already warm air.

Takes too much energy to heat cold air when the heater could be heating existing warmer air already in the house. That was part of the energy efficiency standards that did away with drawing in partial or air outside air during the heating cycle.

Also during the cooling cycle when A/C is equiped on the units and used. Would be like trying to cool the refrig with the door open or heating the house with the front door opened. Makes no sense but older houses had system like these.

Not so anymore. Houses are now built almost air tight to avoid energy loss which is outside cold or warm from entering when doors and windows are closed.

May not be the case up there nor may not have the same installations codes, requirements for energy efficiency or air seperation between breathable air and air exposed to combustion fumes, etc as we have here in the states.

There is something in this equation missing. Appears to me there must be an outside air vent somewhere to allow for combustion air for the heater in that basement, heated or unheated makes no differences.

All gas burning appliances need combustion air. Water heaters and force air furnaces are two of the most common appliances needing huge quantities of combustion air which haa to come from an outside source for proper operation and safety.
 
  #8  
Old 03-16-04, 06:52 AM
Rapid
Visiting Guest
Posts: n/a
Originally posted by Sharp Advice
Rapid

There is something in this equation missing. Appears to me there must be an outside air vent somewhere to allow for combustion air for the heater in that basement, heated or unheated makes no differences.
You are indeed correct! Well spotted.
I just had a look, there is an intake on the heater vented to the outside of the house.
 
  #9  
Old 03-17-04, 11:06 AM
Sharp Advice's Avatar
Admin Emeritus
Join Date: Feb 1998
Location: The Shake and Bake State USA
Posts: 10,398
Received 5 Votes on 4 Posts
Rapid

At this point you could close the intake air vent which is in the basement and inducing cold air into the heater for warming up and circulating in to the house.

There is no known energy saving reasons to heat cold basement air, unless local codes require some outside fresh air be blended into the warm existing air already in the house. Worse yet, air in a basement where the heat is located.

Mixing outside air into the inside air is only required in commerical and or public buildings per our codes. Which may differ in areas not in this climate zone.

Even if the basement air is exposed to a vent capable to bring in fresh air from outdoors. The two airs are not to be mixed in any way regardless of fresh air intake vents to the outside or not.

Since there is a fresh air vent in the basement to provide combustion air, you can than remove that one intake air duct.

If I still understand the original intent of this project., that would be the removal of one ducting tube which is not needed and still have two intakes from inside the house, correct? Yes or No?

Depending on that answer, the project may proceed safely. Removal of the intakes may still pose problems. Alterations of the beams, etc may still be required.
 
  #10  
Old 03-17-04, 01:07 PM
Ed Imeduc's Avatar
Member
Join Date: Aug 2002
Location: Mountain Williams Missouri
Posts: 18,386
Received 0 Votes on 0 Posts
Rapid Do you mean you have two like vent pipes on the furnace that go outside? is the furnace a AFUE 80 or 90 kind? ED
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: