Gas and Oil Home Heating Furnaces - Attic Furnace (Enclosed Area) insulation
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Amistad6
01-15-09, 10:36 AM
We have a Gas furnace in our townhouses attic. It sits in a space that is accesible through a pull down ladder. This area is about 4 x 6. It was framed with 2x4's, floored and walled with insulation and reflective foil facing the inside.
Insulation was "ok" at best to wall this area off, it stays 5 - 10 degrees cooler up there. Some of the foil and insulation needs to be replaced. On the ceiling made with insulation it looks like they intentionally left the top open 6 square inches.
Since this is a Gas heater I'm apprehensive of aggresively insulating this room. I dont want to have an issue with Carbon Monoxide building up in the room. Am I on the right track in my thinking?
The return vents in my house actually just spill out into that room.
Also would it make sense to put a CO2 sensor up there? I have a outlet up there already.
Thanks!
Insulation was "ok" at best to wall this area off, it stays 5 - 10 degrees cooler up there. Some of the foil and insulation needs to be replaced. On the ceiling made with insulation it looks like they intentionally left the top open 6 square inches.
Since this is a Gas heater I'm apprehensive of aggresively insulating this room. I dont want to have an issue with Carbon Monoxide building up in the room. Am I on the right track in my thinking?
The return vents in my house actually just spill out into that room.
Also would it make sense to put a CO2 sensor up there? I have a outlet up there already.
Thanks!
twelvepole
01-15-09, 10:51 AM
CO2 sensor belongs downstairs where you can here it. That's where you are. You don't want CO2 downstairs.
Typically it is the attic floor that is insulated, not the ceiling. Attic should have adequate insulation and ventilation.
"It stays 5 - 10 degrees cooler." Attic temperature should be the same as outdoors.
Warm humid air rises from below. All perimeter gaps, and gaps around pipes, vents, ducts, chimney, etc. should be sealed to keep the warm, humid air out of the attic.
You can insulate a box and place over the pull down stair opening. This can easily be moved over as you enter or leave the attic. Attic stair openings are one of the greatest heat loss areas.
It is not clear what you mean by " The return vents in my house actually just spill out into that room."
Typically it is the attic floor that is insulated, not the ceiling. Attic should have adequate insulation and ventilation.
"It stays 5 - 10 degrees cooler." Attic temperature should be the same as outdoors.
Warm humid air rises from below. All perimeter gaps, and gaps around pipes, vents, ducts, chimney, etc. should be sealed to keep the warm, humid air out of the attic.
You can insulate a box and place over the pull down stair opening. This can easily be moved over as you enter or leave the attic. Attic stair openings are one of the greatest heat loss areas.
It is not clear what you mean by " The return vents in my house actually just spill out into that room."
Amistad6
01-15-09, 01:14 PM
Twelvepole,
Pardon I wasn't clear before.
Picture a standard attic with a room build in the middle of it. This room has walls and a ceiling built from insulation. The kind of insulation on a roll with paper backing. The walls are lined with foil. Picture some of the insulation falling off and some of the ceiling exposed. This room is about 5 - 10 degree's cooler than my top floor. The rest of the attic is like you described.
My GAS furnace is in that room. It seems that the builder intentionally left this room "drafty" because of CO2 emissions. Does that sound right? Would it be ill advised to seal this room better
I have 4 networked Co2/heat sensors around the house, just trying to see if there would be some value to having an extra one by the furnace.
All of my return vents empty into this room, they do not go directly into the heater. This tells me the room is designed to be "room temp". With the room being 5 - 10 degrees cooler I'm loosing some efficiency.
Pardon I wasn't clear before.
Picture a standard attic with a room build in the middle of it. This room has walls and a ceiling built from insulation. The kind of insulation on a roll with paper backing. The walls are lined with foil. Picture some of the insulation falling off and some of the ceiling exposed. This room is about 5 - 10 degree's cooler than my top floor. The rest of the attic is like you described.
My GAS furnace is in that room. It seems that the builder intentionally left this room "drafty" because of CO2 emissions. Does that sound right? Would it be ill advised to seal this room better
I have 4 networked Co2/heat sensors around the house, just trying to see if there would be some value to having an extra one by the furnace.
All of my return vents empty into this room, they do not go directly into the heater. This tells me the room is designed to be "room temp". With the room being 5 - 10 degrees cooler I'm loosing some efficiency.
xpogi
01-18-09, 06:01 PM
Twelvepole,
...It seems that the builder intentionally left this room "drafty" because of CO2 emissions.
I presume you mean CO emissions but lets take a step back. It was probably left "drafty" for combustion air. Does your furnace have a combustion air pipe and a flue pipe or just a flue pipe? If it is a two pipe system there is no need for ventilation in the area where your furnace is, it has sealed combustion and get's it combustion air from outside the house. If it only has the flue pipe it gets it's combustion air from around the furnace and it must be able to get fresh air. There are national and local codes that mandate the size and placement of fresh air inlets to the furnace area if that is the case. By the way if the furnace is installed correctly and not malfunctioning, you don't have to worry about CO emissions (or CO2 emissions for that matter). All of the products of combustion leave your house via the flue. Still, I recommend a CO detector on every floor of the house. Something can always go wrong. Furnace manufacturers spend a lot of time and resources making sure the furnace will shut down if something goes wrong but there is always that pesky Murphy's law.
As far as improving the insulation around the furnace there is no problem with that as long as published clearances to the furnace are maintained (That should be on the nameplate) and as long as you do not impede combustion air.
...It seems that the builder intentionally left this room "drafty" because of CO2 emissions.
I presume you mean CO emissions but lets take a step back. It was probably left "drafty" for combustion air. Does your furnace have a combustion air pipe and a flue pipe or just a flue pipe? If it is a two pipe system there is no need for ventilation in the area where your furnace is, it has sealed combustion and get's it combustion air from outside the house. If it only has the flue pipe it gets it's combustion air from around the furnace and it must be able to get fresh air. There are national and local codes that mandate the size and placement of fresh air inlets to the furnace area if that is the case. By the way if the furnace is installed correctly and not malfunctioning, you don't have to worry about CO emissions (or CO2 emissions for that matter). All of the products of combustion leave your house via the flue. Still, I recommend a CO detector on every floor of the house. Something can always go wrong. Furnace manufacturers spend a lot of time and resources making sure the furnace will shut down if something goes wrong but there is always that pesky Murphy's law.
As far as improving the insulation around the furnace there is no problem with that as long as published clearances to the furnace are maintained (That should be on the nameplate) and as long as you do not impede combustion air.