I'm contemplating tearing down my chimney and putting in a
zero-clearance stainless stovepipe for my oil-furnace instead;

All the stove/chimney/other flue systems I've ever seen have
the pipe from the appliance go up, turn horizontal, and plug
sideways into the chimney stack. Is there any reason
why I shouldn't go straight up from the oil-furnace, through
the roof? It's pretty much open all around.

--Goedjn

"Goedjn" wrote in message
...
I'm contemplating tearing down my chimney and putting in a
zero-clearance stainless stovepipe for my oil-furnace instead;

All the stove/chimney/other flue systems I've ever seen have
the pipe from the appliance go up, turn horizontal, and plug
sideways into the chimney stack. Is there any reason
why I shouldn't go straight up from the oil-furnace, through
the roof? It's pretty much open all around.

--Goedjn

You need a drip leg under the stack. You don't want rain water going
directly into your heater.

Do you mean exit exaust at roof level on a pitched roof with no raised
chimney ? It wont pass code or work, you will get poor draw and
downdrafts in certain winds

"Goedjn" wrote in message
...
I'm contemplating tearing down my chimney and putting in a
zero-clearance stainless stovepipe for my oil-furnace instead;

All the stove/chimney/other flue systems I've ever seen have
the pipe from the appliance go up, turn horizontal, and plug
sideways into the chimney stack. Is there any reason
why I shouldn't go straight up from the oil-furnace, through
the roof? It's pretty much open all around.

--Goedjn


Depends.
The International Mechanical Code, what most areas in the US are using will
still require a particular height above pitch for your furnace exhaust. You
may find that that bright stainless pipe sticking so far up on the roof will
be far worse looking than a chimney.

If you do it, check the local codes first. Read Mechanical Code section
804.3.5
BTW, drip legs are not to code, as section 5, of 804.3.5 clearly states. and
this will also add an additional 15 to20 feet total effective length (TEL)
to your exhaust, and as each make of furnace has a total length, you may
find that you have exceeded this with a so called drip leg.

Since you have what is called a forced draft system (oil) you will also have
to insure that each joint is sealed properly. Code section 804.3.1

And I hate to look like I am busting on everyone that has replied so far,
but Mark is wrong about the draft. Oil units are forced draft, therefore
draw isnt an issue since the exhaust will be a positive pressure style.

If you dont mind, why are you considering this? I mean....most people do not
want a mobile home style roof jack on their home.

All oil units are forced draught , Yea I never had one, ok I learned
something,

You need a drip leg under the stack. You don't want rain water going
directly into your heater.


Ok, does this drip leg need some mechanism for draining the water
out, or is there little enough of it that it's expected to evaporate
by itself?
Looking at the retrofit chimney liner retrofit kits, there doesn't
seem to be any such mechanism, just a cap for the bottom of
the T. And with a rain-cap there shouldn't be very MUCH outside
water.
What code book covers the rules for this sort of thing?
Is it buried somewhere in the building-code, or do I need
to go find the mechanical code-book, too?

--Goedjn

"Goedjn" wrote in message

Ok, does this drip leg need some mechanism for draining the water
out, or is there little enough of it that it's expected to evaporate
by itself?

Not just water, but dead birds, squirrels, etc get in there You want to be
able to clean it out in some manner.



What code book covers the rules for this sort of thing?

I have no clue.

If you dont mind, why are you considering this? I mean....most people do not
want a mobile home style roof jack on their home.


Largely because my masonry chimney is loosing bricks, and
I can't seem to get any professional to do more than
come look at it and say "wow, that's bad"...

I may decide to just rebuild it myself, since the stainless
metal chimneys, while easier, don't appear to actually
be CHEAPER than a masonry chimney, except for the
labor. And since it looks like I'll have to do it myself
anyway, that matters less than it might.

Basically, at the end of this month, I shut the
furnace off, cut a hole in the roof, tear down about 11' of
chimney down through the attic, and staple a tarp over
the hole. I then have until late october to get something
up that costs me less than $7,000 and lets me run the
furnace again.

--Goedjn

"Goedjn" wrote in message
Largely because my masonry chimney is loosing bricks, and
I can't seem to get any professional to do more than
come look at it and say "wow, that's bad"...

I may decide to just rebuild it myself, since the stainless
metal chimneys, while easier, don't appear to actually
be CHEAPER than a masonry chimney, except for the
labor.


I don't know how much of it would be considered DIY, but could you learn to
do brick pointing?
Next would be a liner of some sort that goes down from the top. No that we
know the problem, perhaps others have better solutions.

In article bES7e.5180$ha3.2598@trndny02, says...

"Goedjn" wrote in message

Ok, does this drip leg need some mechanism for draining the water
out, or is there little enough of it that it's expected to evaporate
by itself?

Not just water, but dead birds, squirrels, etc get in there You want to be
able to clean it out in some manner.

Also, depending local climate, and on how much of the flue runs
through un-heated attic and above the roof line, you may get
significant condensation inside the pipe.

--
is Joshua Putnam
http://www.phred.org/~josh/
Books for Bicycle Mechanics and Tinkerers:
http://www.phred.org/~josh/bike/bikebooks.html

I've seen quite a few homes that have metal flue inside with a
decorative masonry "chimney" above the roof line. Don't know
what code requirements are for this, but as long as you're going
to have to look into your local code requirements anyway, it
might be an option to consider.

--
is Joshua Putnam
http://www.phred.org/~josh/
Books for Bicycle Mechanics and Tinkerers:
http://www.phred.org/~josh/bike/bikebooks.html