How do I accurately figure out where air is blowing out from, from my
furnace flue area, which is next to my hot air duct.

I'v used a match, but it keeps blowing out. Tonight I took a pencil
and thumbtacked a thin strip of cellophane-like stuff to the end of
it. Later I added a narrow strip of thin cloth. They blow like
crazy when the pencil is on the right side of the flue, but I can't
seem to narrow down where the origin is.

The furnace is a rectangular box, with the heated air duct attached to
the top and going up from there. The fire exhaust comes out the
front side just below the top, into the flue collector, a metal box
which was rebuilt last week and is 14" wide, almost as wide as the
furnace, and 5" high and 8 inches deep. On the top side of it
connects the 6" round flue.

When the pencil and its flags are on the left side of the flue, no
breeze is detected. But in front of the metal box in the middle,
and anywhere above the box to the right of the flue, the "flags" on
the pencil blow around like crazy. I'd like to narrow down where the
air is coming from.


Background:
You've all convinced me that I need to buy a new furnace, and I will
this year, but I don't want to rush, so I'm still using my old oil
furnace until I have time to get recommendations, prices, etc.

As I described in a previous post more than a week ago, I had the flue
collector repaired by a welder. As Eric predicted, when he welded one
place, he made a new hole next to the weld.

So I filled all the holes with GE Red Hi-Temp Silicone, which it says
is good to 650 F intermittent (and a tube from 10 years ago said it
was good to 600 F.) And it doesn't seem to get anywhere near that
hot. And the "glue" is certainly in good condition only a week
later, though perhaps it's not sticking everywhere I think it is.
Maybe air is escaping. I'll put on more layers, but I'd like to know
first where the leaks really are. It's not that cold and I won't be
running the furnace until the leaks are stopped.

When the burner starts, no air comes out through the repaired

"mm" wrote in message
...
How do I accurately figure out where air is blowing out from, from my
furnace flue area, which is next to my hot air duct.

I'v used a match, but it keeps blowing out. Tonight I took a pencil
and thumbtacked a thin strip of cellophane-like stuff to the end of
it. Later I added a narrow strip of thin cloth. They blow like
crazy when the pencil is on the right side of the flue, but I can't
seem to narrow down where the origin is.

You can buy a smoke pen or light one of those incense things that smoke.
They will generate smoke, but by smoldering, no open flame to blow out.

On Thu, 5 Nov 2009 21:31:58 -0500, "Ed Pawlowski"
wrote:


"mm" wrote in message
.. .
How do I accurately figure out where air is blowing out from, from my
furnace flue area, which is next to my hot air duct.

I'v used a match, but it keeps blowing out. Tonight I took a pencil
and thumbtacked a thin strip of cellophane-like stuff to the end of
it. Later I added a narrow strip of thin cloth. They blow like
crazy when the pencil is on the right side of the flue, but I can't
seem to narrow down where the origin is.

You can buy a smoke pen or light one of those incense things that smoke.

Good idea. I have an incense stick. No, I diddn't buy it. I'm no
hippie. It was probably in the apartment I used to have when I moved
in 38 years ago. I put it in a vase and it's still there, I think.
(I've only moved once since then.)

I figured it might come in handy, and 38 years later, it will.

If that doesn't work, I'll look for a smoke pen.

They will generate smoke, but by smoldering, no open flame to blow out.

On Thu, 5 Nov 2009 21:31:58 -0500, "Ed Pawlowski"
wrote:


You can buy a smoke pen or light one of those incense things that smoke.
They will generate smoke, but by smoldering, no open flame to blow out.

And thanks.

On Thu, 5 Nov 2009 21:31:58 -0500, "Ed Pawlowski"
wrote:


You can buy a smoke pen or light one of those incense things that smoke.
They will generate smoke, but by smoldering, no open flame to blow out.

I found it. It's either an incense stick or a very tiny corndog.

On Thu, 05 Nov 2009 23:40:24 -0500, wrote:

On Thu, 05 Nov 2009 20:36:53 -0500, mm
wrote:

How do I accurately figure out where air is blowing out from, from my
furnace flue area, which is next to my hot air duct.
Get some small diameter hose, 3/8 or so. Hold one end up to your ear
and probe around where you think the air is coming from with the
other. When you get close it will sound like a hurricane.

Also a very good idea. In my case maybe a better one because my 30
year old incesnse didn't burn well.

I will check for wind tomorrow again, but tonight I had decided it was
coming from the outer surface of the firebox, at the top by the heat
exchanger, and when it cooled and I put my hand in, fingertips up, it
turned out there was a wide but shallow opening from the warm air
duct. Not from the exhaust gases at all but from the warm air duct to
the heating ducts. That explains why the breeze was only there after
the main blower fan turned on. I don't remember if I had this before.
I guess I must have.

Surely it's okay to plug this hole, right?

I usually run my hand an inch or so away from the flue or
duct. I can feel the escaping air.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"mm" wrote in message
...
How do I accurately figure out where air is blowing out
from, from my
furnace flue area, which is next to my hot air duct.

I'v used a match, but it keeps blowing out. Tonight I took
a pencil
and thumbtacked a thin strip of cellophane-like stuff to the
end of
it. Later I added a narrow strip of thin cloth. They blow
like
crazy when the pencil is on the right side of the flue, but
I can't
seem to narrow down where the origin is.

The furnace is a rectangular box, with the heated air duct
attached to
the top and going up from there. The fire exhaust comes
out the
front side just below the top, into the flue collector, a
metal box
which was rebuilt last week and is 14" wide, almost as wide
as the
furnace, and 5" high and 8 inches deep. On the top side of
it
connects the 6" round flue.

When the pencil and its flags are on the left side of the
flue, no
breeze is detected. But in front of the metal box in the
middle,
and anywhere above the box to the right of the flue, the
"flags" on
the pencil blow around like crazy. I'd like to narrow down
where the
air is coming from.


Background:
You've all convinced me that I need to buy a new furnace,
and I will
this year, but I don't want to rush, so I'm still using my
old oil
furnace until I have time to get recommendations, prices,
etc.

As I described in a previous post more than a week ago, I
had the flue
collector repaired by a welder. As Eric predicted, when he
welded one
place, he made a new hole next to the weld.

So I filled all the holes with GE Red Hi-Temp Silicone,
which it says
is good to 650 F intermittent (and a tube from 10 years ago
said it
was good to 600 F.) And it doesn't seem to get anywhere
near that
hot. And the "glue" is certainly in good condition only a
week
later, though perhaps it's not sticking everywhere I think
it is.
Maybe air is escaping. I'll put on more layers, but I'd
like to know
first where the leaks really are. It's not that cold and I
won't be
running the furnace until the leaks are stopped.

When the burner starts, no air comes out through the
repaired