Cold air coming through the ducts?

[LLigetfa]

OMG! What a hack job. Whoever did that should get their license pulled. OTOH the guy probably didn't have a license. There is not supposed to be a cold return that close to the furnace. A register of that size that close pretty much negates all the other cold returns as it can short circuit the path.

Remove that last section of duct that has the register cut into it. Mount a proper filter housing next to the furnace. Get the kind that hold a 4 inch thick filter as they have better surface area.

How many sq inches of warm air supply is there to that cellar space? There is supposed to be twice the area of warm registers to cold return.

 

[woodjack]

OMG! What a hack job. Whoever did that should get their license pulled. OTOH the guy probably didn't have a license. There is not supposed to be a cold return that close to the furnace. A register of that size that close pretty much negates all the other cold returns as it can short circuit the path.

Remove that last section of duct that has the register cut into it. Mount a proper filter housing next to the furnace. Get the kind that hold a 4 inch thick filter as they have better surface area.

How many sq inches of warm air supply is there to that cellar space? There is supposed to be twice the area of warm registers to cold return.

Can I just cover the register with sheet metal and caulk the seams? Or, are you saying to remove the section of duct so I can insert a filter mount in that spot? How will I detect if the system is starved for air?

Also, There are two return registers in my living room - there's a register very near my woodstove in my living room that I keep covered even when the furnace kicks on because I didn't want it sucking out my precious warm air (there was no woodstove when the forced air system was designed.) Is that a mistake? And there's an additional register in the living room.

I'm not sure if this is what you're asking, but the warm air supply duct and the return ducts are approximately equal in size in the furnace room.

 

[LLigetfa]

Yes, remove the section so you can install a proper filter holder.

As I mentioned, a calculator will tell you if/how much cold return you need if you need any at all. Many open cellar installations don't have any cold returns at all. Check with a reputable licensed installer, but if you do, be prepared to do immediate remedial work as they could tag it as unsafe for human habitation.

 

[woodjack]

Yes, remove the section so you can install a proper filter holder.

As I mentioned, a calculator will tell you if/how much cold return you need if you need any at all. Many open cellar installations don't have any cold returns at all. Check with a reputable licensed installer, but if you do, be prepared to do immediate remedial work as they could tag it as unsafe for human habitation.

I thought it might be inefficient, but not unsafe.

 

[smokinj]

I use my oil, forced air system as a back-up to my wood heat, but the ducts are cold air channels to my living space from the basement/furnance room. I cover the vents with towels, but then they're closed if the heat kicks on. Do any of you guys have this problem - and a solution?

I had this problem but now i heat the craw space with two runs off the wood furance! (i know this dont work for most but i tryed everthing before doing this craw space is at 50r plus) now the space is running between 70-78 degrees

 

[LLigetfa]

The unsafe part is when the furnace fan sucks air and lowers the pressure in the cellar which steals draft from naturally aspirated appliances. People in their quest to lower their fuel bill start closing off all the warm air registers with the idea of not heating the cellar. Then they start sealing all the cold drafts they find feeding air to the cellar that these naturally aspirated appliances need to function properly. The resultant lowering of pressure may cause CO to be drawn into the home and we read or hear about the tragedy in the news.

I don't really want to be an alarmist, but this is a scenario that plays out far too often. People that don't have a basic understanding of properly balanced HVAC, should leave it to the pros.

BTW, I am not a licensed HVAC pro, nor do I play one on TV and I have not stayed at a Holday Inn Express recently, but I have worked with the pros and have some familiarity with the principles that govern the codes they work by.

 

[woodjack]

Thanks for explaining.
There's an 6" duct letting outdoor air into the boiler room that I guess addresses the lack of air concern. That being said, my system probably needs to be re-analyzed.

I try to be a Do-It-Yourselfer to save money, and have too much respect for people's time than to call a professional for an estimate, just to get free advice. . . so thanks for all your help.