Another kind of winter ventilation question

[jaybee]

Who has a setup to extend exhaust pipes safely outside the garage so the overhead door can stay closed?  How did you build it?  Considerations and limitations?  Suitable materials?  After all, Carbon Monoxide poisoning isn't a repeatable option, but working in single-digit temps isn't all that appealing either.

[40]

John,a buddy of mine has 2 openings in his garage doors that have metal covers that swing in a circle that open/close as needed...they are approximately 2 1/2-3" in diameter.He then has a couple of pieces of metal flex tubing that he attaches to the tailpipes and runs them thru the "traps" in the overhead doors.It works great...the inserts in the doors are "factory made" but unfortunately they were there when he bought the house/garage.I have thought about adding something like this to my shop but haven't checked with my overhead door suppliers to see if they have such an "insert" available.You're right....it's 10 below zero outside now and way too damned cold to have the door open!

[Bob Paulin]

John,a buddy of mine has 2 openings in his garage doors that have metal covers that swing in a circle that open/close as needed...they are approximately 2 1/2-3" in diameter.He then has a couple of pieces of metal flex tubing that he attaches to the tailpipes and runs them thru the "traps" in the overhead doors.It works great...the inserts in the doors are "factory made" but unfortunately they were there when he bought the house/garage.I have thought about adding something like this to my shop but haven't checked with my overhead door suppliers to see if they have such an "insert" available.You're right....it's 10 below zero outside now and way too damned cold to have the door open!

I believe such a setup offers a false sense of security.....

The loose fit of the exhaust tubes around the tailpipes WILL leak a goodly amount of CO into the shop unless a blower has been set up to create a negative pressure at the tailpipe/exhaust tube connection.

Prevailing air movement outside might even actually blow inward on the exhaust pipes sticking out the door, forcing MOST of the CO back into the shop......

.....unless something has been set up to positively suck the exhaust away from the tailpipe and force it outside - something like a flea market/lawn sale squirrel-cage blower.

ALSO....increased exposure to CO does NOT build an immunity, rather just the opposite....it increases SENSITIVITY to CO......no matter how little the exposure!!!!

PIA to set up something of this nature?......Yes!!!

Better, however, than spending time in the hospital with CO poisoning resulting in life-long condition and sensitivity such as NASCAR driver Rick Mast now suffers from, which forced him to quit driving a race cars......or an even more "permanent" condition which causes you to assume room temperature......

B.P.

[40]

I would have to agree that a system as you describe is no doubt a better/safer way to go.Jeff does have a flexable collar that is clamped to the flex tube and then stretches over the tailpipe....not an absolute air tight set-up I'm sure but for running a car on occasion for short periods of time...it seems to work out OK.To my knowledge,it has never set off the CO detector in the shop and I don't recall ever smelling exhaust while at his shop.I can definately see where outside conditions such as a straight-on wind could negate the pressure of the exhaust and cause a problem.Thanks for the post....I'll have to give a pressurized system some thought.Perhaps a little electric fan motor used in the duct work of a gas water heater would do the trick and could be easily incorporated into the piping.As you stated better to be safe.....I'm in no hurry to become "Room Tepurature"

[Sean]

The loose fit of the exhaust tubes around the tailpipes WILL leak a goodly amount of CO into the shop unless a blower has been set up to create a negative pressure at the tailpipe/exhaust tube connection.

The mechanic I worked for back when I was a kid used a set-up like that, but the hoses were made of a rubberized black cloth type material reinforced with a wire spiral on the inside. Anytime we were going to use them for more than a few minutes, we used hose clamps to make sure the connection was tight. That was on full exhaust systems though, short exhaust systems would probably get too hot for that type of hose.

If we were working on the cooling system or something where the vehicle was running for an extended period of time for diagnosis, we poured just a little bit of tranny fluid down the Carb. If you shine a flashlight under the length of the exhaust system, you can see smoke from the tranny fluid if there are any leaks.

The guy I worked for was pretty anal about stuff like that because a friend of his died while working on a car. He said the guy had the garage door raised about a foot, but it obviously wasn't enough...

[Dave]

Who has a setup to extend exhaust pipes safely outside the garage so the overhead door can stay closed?  How did you build it?  Considerations and limitations?  Suitable materials?  After all, Carbon Monoxide poisoning isn't a repeatable option, but working in single-digit temps isn't all that appealing either.

Northern auto parts.
http://www.northernautoparts.com/
They have all the stuff your looking for to get exhaust thru a door
Dave

[jaybee]

A lot of good stuff to think about.  Today I ended up backing the car out so that the whole trunk was outside and closing the door to just off the trunk lid.  Sure enough the breeze brought the exhaust right back into the building at times.  I've heard of cases where people were poisoned by opening the garage door a crack thinking that would give enough ventilation.  I made quick work of my task and got the heck out.

Great idea to use an old squirrel cage blower to create negative pressure.  I've seen professional systems that work on that very principal.  I already have a used furnace blower and it's great to have.  Dries a damp floor in short order and in the Summer it'll take cooler air from just outside the building and blow it clear to the back.  It could also be used to pressurize a temporary spray booth with filtered air, just like the pros use.  Making a plenum for exhaust pipe hoses would be a piece of cake, something that could be removed to keep the blower usable for other purposes.  Same with sleeving the garage wall so that it could blow outside.  Maybe the most important part would be the door or shutters to the outside to keep the weather out.

[Bruce Dorsi]

<snip>...Same with sleeving the garage wall so that it could blow outside.  Maybe the most important part would be the door or shutters to the outside to keep the weather out.

Could  you use a clothes dryer vent through a sidewall of the garage?

....You could also put a cap over the inside end when not in use, to minimize cold air seepage.

[jaybee]

<snip>...Same with sleeving the garage wall so that it could blow outside.  Maybe the most important part would be the door or shutters to the outside to keep the weather out.

Could  you use a clothes dryer vent through a sidewall of the garage?

....You could also put a cap over the inside end when not in use, to minimize cold air seepage.

That's very good.  I already have everything to make this work except for the hoses.  I gotta try this.

[Bruce Dorsi]

....You could also put a cap over the inside end when not in use, to minimize cold air seepage.

....Hummmmmm! ---That's strange!

Why did my post get sensored?  

....The ##### was actually where I typed "put" and "a."

[OlBuzzard]

Maybe you forgot a space between <put> and <a> and we would have a word most Texans, New Mexicans and Arizonians would recognize!

[Bruce Dorsi]

Maybe you forgot a space between <put> and <a> and we would have a word most Texans, New Mexicans and Arizonians would recognize!

.....That was my first thought, as well.  However, even with the space there, it was rejected.

The word you refer to, is also well-known up here in the Northeast!

[river1]

*  put a  pu ta p uta

well i tried all versions (spaces in different places) of that four letter word we'll see what happens

later jim

ps edit-it censored them all

[Fat Cat]

Maybe you forgot a space between <put> and <a> and we would have a word most Texans, New Mexicans and Arizonians would recognize!

Which is why it was getting censored. I installed a new word censor routine and it was going a little over the top with a few words. So I paired down the filter list in an attempt to limit things like this from happening again.

[Crosley.In.AZ]

the main thing is to be careful with exhuast fumes...

we have already had a pair of dim wits nearly die using a BBQ in doors to warm the apt up here in the valley of the sun.

10-12 years ago I had a neighbor that her daughter and boy friend died from using a bbq for heat... the grand son was at grandma's house ( my neighbor) that night ...

let's be carefull