Furnace air intake line.

[The Grebe]

We used to have an old gravity furnace and changed over to forced air, 4-5 years ago.

When the boys were home, they had their bedrooms in the basement and it was a little cool at times, but never cold....good for sleeping they said. With the forced air, they would have died from hypothermia down here!

Man, since we got this furnace, it's colder then a well diggers a$$ down here...I believe it has something to do with the air intake line from the outside? I heard that if you put a 5 gallon bucket over the end, this allows air in, but somehow contains it from dispersing? I heard about that yesterday and today I put one on it.

The insulated intake line already has some kind of galvanized box surpressor on the floor end, but it still gets really cold around that thing?

It was livable down here before and nothing has changed down here except that furnace and it's intake, so I would think that would be the first place to look? Any suggestions?

[sparcebag]

In the duct work down there do you have any registers that blow warm into the basement?Also are there air returns fron the interior of upstairs?

[The Grebe]

Yup, there is one, but the heat opposed to the cold, is equivelent to trying to light up a fish house with a farmers match! I leave it hsolist;osed to direct the heat where it will be better utilized.

Yup again, there are floor cold air returns in each room of the house.

[sparcebag]

With that register closed expect no heat there.With it open it may take time but it will be warmer,Why do you think its there?

I tried to send you email and it was rejected,Add. from profile.

[Roofer]

I'm not quite sure if I understand all of this, but whoever told you to cover something with a 5 gallon bucket should be shot. Who put it in for you? Maybe they would know. You can't ask a barber about your car and you can't ask a mechanic about your hair. Ask the professionals. It may save you or your family's life.

[fastkaw]

Roofer is absolutely right.

Make up air is not return air.

If your basement is cold you need to add a return air in the basement close to the floor. Put a register on it instead of a grill so you can open it in the winter

and close it in the summer. You don't wont to pull back the cold air in the basement

in the summer time.

[timjones]

I know what Grebe is talking about. He isn't covering the air intake he is just dumping the cold air into a five gallon bucket on the floor. We had a new furnace put in a couple of years ago in the house we still have in the cities. It was required by code that the burner have an external cold air source. The installers put in a flexible duct(6 or 8 inch) to a vent installed on the outside of the house and then ran it down to about a foot off of the basement floor. They told me to put a five gallon bucket or other container on the floor with the duct inside. The purpose was to keep the cold air in the winter from blasting right in and scattering all over the basement. It may help some but when the wind is blowing from that side of the house it really gets cold down there. It never did before with the old furnace. Yes I have a heat vent down there, two as a matter of fact, but they are only putting out heat while the furnace is running. The cold air intake is putting out cold air constantly. Definite advantage for the cold air.

[reddog]

I think you are talking apples and oranges/

If there is a line coming into the furnace room, say a 6 inch. that dumps out near the floor, it is a supply line for combustion air and it is not uncommon to put a bucket at the end of the line for the reasons mentioned. If your furnace needs combustion air, then it is probably an 80% efficient furnace, and will either have a simple draft type flue, , or a draft induced flue with a fan on it to make sure that the unit doesnt backdraft.

If the furnace vents horizontally, it is probably a little more efficient furnace, and brings in its own combustion air.

Make up air, is air that is brought into a mechanically ventilated home, to balance the system. That could be an air to air exchanger, or an exhaust only system.

[Roofer]

Some good info reddog. I hope you can educate us some more. It is a fact most homeowners don't know how their furnace works or their house. Brace yourself, but some owners don't even know it has a filter..........

[fastkaw]

Hot air go's up cold air falls.

If you don't pull the cold air off the floor in a basement it will never be as worm

as it should be.

As for the building+zoning bin sold a pile of dodo it's hard to say.

Yes a house/furnace need make up air. Especially if it's a tight home.

I think your HVAC guy cheeped out. If he had sold you a furnace with a two pipe

system or a sealed combustion furnace you would not need the pipe as you described. If you have a tight house you need a Air to Air heat exchanger.

If it was my house id stick a sock in it.

If I had a wood burner in the house id have a air to air heat exchanger.

Osakis

I fished that lake 45yr. ago. lots an lots of crappies Had a great time.

We stayed at a resort called Blacks Resort. I think it was on the west side,

do you know if it is still there?

[The Grebe]

Sparce...thanks for the reply...it goes without saying that the register down here is used for heating...what I'm saying is that in no way, shape or form is that one register going to heat this basement...surely you would have to understand that that would be one of the very first things a person would try.

Now put in another way, how much luck would a person have towing a mobile home with a Volkswagen? It just doesn't get the job done and the thermostate, set at 72, kicks out long before there is any heat build up in the basement.

[The Grebe]

Roofer...Well, I don't know about shooting anyone, but the intake isn't covered, or blocked off, it is set into the 5 gallon pail, which supposedly allows plenty of air to supply the furnace, without the fear of carbon Monoxide, but keeps unnecessary cold air from entering?

I've heard about this on 3 different occassions, from 3 different sources....one of the sources may have been an article in last weeks Mr. Fix It column? Don't quote me on that, I say that might be one of the sources, I'm not sure. I don't know the dynamics of this proceedure, I thought someone here might? It might be an old wives tale, I don't know.

[The Grebe]

BINGO!

[beaver11]

do u have a water heater near by.more than likely that fresh air box is for that.that furnace should be fine pulling in air from your basement.how big is your house?(sq. ft.) if it's pretty big you might want to think about putting in a zone system. that allows u to put a thermostat in your basement then when it calls for heat it closes a damper to your upstairs,opens the downstairs damper and only heats that. but first i would start by going the cheaper route and add a few more heat runs in your basement and try that first.

[timjones]

fastkaw,

Blacks is on the SE corner by town. It's not a resort anymore. About 3 or 4 years ago it joined the ranks of the other resorts that have sold the cabins and become a ?(sorry, senior moment and I can't remember what they are called). But it's where people buy the cabins, pay a monthly fee, and then the people that used to run it as a resort maintain the grounds and put the docks in, things like that.

[The Grebe]

Yeah, I was kind of wondering, even if all the cold air down here was returned to the furnace, if it wasn't running, it wouldn't do alot of good. The water heater is near by and you may be right about that? The thermostate thing sounds like something that might work?

First thing I did was call the company that put it in, but they don't seem to be in to big of a hurry to call me back! Other companies aren't all that keen to talk to you if it wasn't their install...can't really blame em. I'm gonna call them again tomorrow and if the call isn't retuned, on Tues. I'm gonna take a drive over there and see if there is someone that is willing to offer some input. Thanks for the positive!

[Surface Tension]

So your saying you have a 6" air intake line that isn't connected to the furnace, rather it just dumps into a utility room.

I'd imagine that would be to supply the furnace, hotwater heater, cloths drier with combustion air, also and most importantly sized according to how many exhaust fans you have in the house. That would be bathroom and kitchen exhaust fans. A tight house with exhaust fans will pull air from your furnace, drier, and hot water heater, thus the 6" intake.

One heat register in a basement isn't enough. Add another register in location across the room from a cold air return. Under a window or next to a door is ideal.

You could also add a Duct Booster Fan to that register to increase the volume.

[MNice]

It wouldn't hurt to call your inspector. I am a plumbing/mechanical inspector for a metro city and we help people out with heating/plumbing problems all the time.

It's real hard to diagnose a problem like yous without actually seeing the problem. More than likely, the air intake you describe is your combustion air, many times if you simply trap it by having the duct terminate with a "J" so the opening is about 12-16" off the floor, it should slow down the cold air from entering. The theory behind this is to keep you furnace room from going negative in pressure and unless there is air going out of you house through exhaust fans, there should not be much air coming in. If you house is older and not tightly sealed, The code does not an require outdoor combustion air duct but many contractors install it as their "normal" installation package. The code has a formula for calculating air infiltration for older homes to provide the necessary combustion air .

If you only have 1 supply air in your basement, you are behind the 8 ball, it will not do a nice job.

Hope you can make some sense of my ramblings

[LundExplorer]

So far I think that reddog and Surface Tension have got the idea here, these vents are for combustion air for the furnace and water heater, etc.

And I wouldn't go about shooting the guy with the pail idea nor do I think its a wives tale either. In fact, the MN Blue Flame Gas Association suggests the same pail idea on their web site,blueflame.org.

The idea behind it is that it acts like a thermal dam, the incoming cold air is trapped in the bottom of the pail rather than spreading across the basement floor. Its cold air, so it can't go up & out of the bucket unless pulled out (like when the furnace is on).

I would not stuff a sock in it either since it is there for combustion air supply & prevents backdrafting which can cause a CO buildup, bad news.

[Roofer]

Sorry, I stated at the beginning that I may not understand what he was doing. Just being cautious is all.

I agree with calling the inspector.

[sparcebag]

 Originally Posted By: Roofer

Sorry, I stated at the beginning that I may not understand what he was doing. Just being cautious is all.

I agree with calling the inspector.

Roofer not gettin on ya here this is general,But I notice this alot,people give advice,and there's multiple choices,It just confuses someone who asking advice,Lots of advice is 2nd hand,heresay,or just unknowleged opinions.It could lead to a unknowing person creating a hazzard in this case.In other cases just shoddy work,or 5 steps to accomplish what could be done in 2.Just my opinion here.

[Hookmaster]

When I had the furnace and AC replaced in 1995 the installers did the same thing, 6" supply line. I put the end in a 5 gallon bucker making sure the duct wasn't tight against the bottom of the bucket so the furnace, water heater and dryer could pull combustion air when needed. If you don't have some kind of trap, the cold air will continue to flow in at times.

Before the install, my basement had to ceiling heat vents. I said I wanted more. They added one more ceiling vent and 2 floor level vents and more importantly a cold air return since there was not one before. My basement still can be 6 degrees colder than the main floor but that's what the gas fireplace is for.

[POPS57]

That intake is so when your furnace runs it gets its makeup air from it. If you did not have that fresh air duct it will get its makeup air somewere else. Like around windows,doors and that is where you get drafts in your house. The trouble with your system is they installed the line the cheapest way they could. There are two ways to fix your problem. One would be to connect that line into your cold air return to the furnace. Or if you want it done the best way you would install a air to air exchanger. You also need to adjust your vents dif. summer and winter. More vents downstairs wide open damper the upstairs one's down. This forces more air downstairs. Change them 180 for summer. Close the door to the upstairs all the time.

[The Grebe]

To all...I got exactly what I was looking for, intel to formulate a plan of action...there's some good stuff here and with it, I won't have to plug anyone and might even end up with a warmer basement.

Time to call the original installers for the 4th time (An established outfit to, not a fly by nighter.) and if I can't talk to someone there, I like the idea of calling an inspector who can give me the exact skinny on what we should do....thanks again guys!

[Shack]

I believe (and this could have been stated by MNice), but the fresh air intake should come inside, extend of by furnace, water heater, ext. ,come down the floor and "U" back up about 12' or what even code is. This is how mine is.

Now I have a friend (in h-vac industry) and he puts a small light weight cardboard box (shoe box type) over the fresh air intake outlet (pointing up to ceiling). He says this box acts like a dampener. When air is needed, it pulls/pushes it threw (I would assume) and when air is not needed, dampens the flow of cold air into the house. Its not a tight seal of sorts at all and the downward postion of the walls of the box direct air down words (as if cold air does not go down). I leave mine as it was intended, but I thought I would bring it in this thread. He has no cold air returns yet in basement (unfinished) and has lived in the home since 1997 (built in 97). I question the effective ness of his theory and the possible health/hazard issue behind this at one time. He then went up stairs, turned on the exhaust fan in the bathroom and you could see box move a little. You could defiantly feel air flowing down ward to floor. Once the fan was shut off, the cold draft slowed down to almost nothing (you could still feel a little). He then removed the box and you could feel cold air slowly coming out again (drawing for some reason, no water heater, furnace or fan was on. Possibly a leaky window).

It never sat right with me doing this, but I guess he has been alive now for 10 years.