Hot Air Gas Furnace 80,000 BTU Backdrafting/Negative Pressure

[rgs03833]

Hi Everyone,

I need a little help on my Furnace

I have an 80,000 BTU Natural Gas Furnace that the Auto-Draft Flue Fan is going up to the Chimney. I would say about 10 Feet up, but I think my Chimney have Leaks... Because everytime the Furnace is on, I find this Foul Smells right below that Room / 2nd floor since it's on the 3rd Floor.

I can't really explain the Smells, but it makes me choke sometimes. On top of that, I have an older guy living on the 3rd Floor and I think he is sneaking Cigarette Smoke here and there. So when the Furnace is on, the Cigarette Smoke and that CO2 combined, that may have made things worst?

I wonder 1. if that is the Problem and 2. how would you fix it?

Another suggestion is that get a Liner and run that up and put a Cap on top of the Liner.

Also, there is an Apartment Downstairs/ 1st Floor, they are also complaining that they smell Smokes sometimes too, an hour later to be exact. I was wondering, that since my house is old and NOT well insulated that it is leaking down because of Hot / Cold air would Settle?

Anything would be greatly appreciated, thank you!

 

[zzvyb6]

Look for a dead animal stuck in the flue. Also, my furnaces vent directly outside thru a basement wall. I don't believe a conventional chimney provides the proper draft/convection pattern for a direct vent furnace. There's not enough heat to exhaust the stack.

 

[KennyG]

I think you need to call in a professional immediately. If this is a high efficiency furnace that can be vented with plastic pipe, it should not be going into a chimney and shouldn't cause any smells at all.

Assuming it is not a high efficiency model, if you smell smoke, something is burning and it isn't natural gas. You either have something stuck in the chimney or you have a damaged chimney and you are slowly burning the house down. Get this looked at immediately.

 

[murphy1244]

Hi Everyone,

I need a little help on my Furnace

I have an 80,000 BTU Natural Gas Furnace that the Auto-Draft Flue Fan is going up to the Chimney. I would say about 10 Feet up, but I think my Chimney have Leaks... Because everytime the Furnace is on, I find this Foul Smells right below that Room / 2nd floor since it's on the 3rd Floor.

I can't really explain the Smells, but it makes me choke sometimes. On top of that, I have an older guy living on the 3rd Floor and I think he is sneaking Cigarette Smoke here and there. So when the Furnace is on, the Cigarette Smoke and that CO2 combined, that may have made things worst?

I wonder 1. if that is the Problem and 2. how would you fix it?
.
Another suggestion is that get a Liner and run that up and put a Cap on top of the Liner.

Also, there is an Apartment Downstairs/ 1st Floor, they are also complaining that they smell Smokes sometimes too, an hour later to be exact. I was wondering, that since my house is old and NOT well insulated that it is leaking down because of Hot / Cold air would Settle?

Anything would be greatly appreciated, thank you!

If that furnace is a 80+ eff it needs a chimney liner . 90+ units go in pvc.

 

[freddyr]

yep chimney needs lined, very common with the 80% furnace. to much moisture on old flue liners which erodes the cement.

 

[Egon]

Sounds like the chimney will a portion that is negative pressure and the portion above the exhaust fan will be positive pressure.

So you could be sucking in and forcing out air from outside of the chimney???

As suggested a liner may solve the problem.

 

[rgs03833]

Hi, I think almost Everyone here agreed that it needed to be Lined!

That is what I will do, I will try that this weekend and then repost an update and the report.

Thank you all for being here when I needed you all most !!! :thumbsup:

 

[rgs03833]

Hi you guys,

Here is the Update on the Furnace.

Everything went well just took a bit to string the darn thing out of the Chimney, since i'm afraid of heights. Also, I did the 1st Floor Furnace as well that took a while since I had a 50' Flex Pipe and only cut 3' off . 47' stringing up with about 7" hole from the 3rd floor it wasn't FUN .

Happy to report that the Smells is gone, but now I found another problem .... Intake

My next thing is to cut 2 Holes in the wall and Pipe in fresh air from outside into the Furnaces, so the Furnaces doesn't draw the air from the Basement or Attic out because I have 2 Furnaces . Now I know why I get cold drafts and funky smelly stuff that kept me up at nights.

Thankx to all again...