I posted a while back on trying to quiet a noisy flue out of a forced hot air heater. Makes a huge whoooooshing noise when it is fired up, It exits the house in a two inch schedule 40 pvc pipe.
From the discussion it became obvious that having air go through an adapter to 3 inch and then back to 2 inch again (making a primative muffler) would help quiet it down.
The pipes exit the house at about 4 feet above ground level, and I was wondering if there would be any forseeable problems if I ran a 90 degree elbow, and then built the muffler vertically with the gasses being pushed out the wall and then going down
my basic design looks like this shop vac quieting system:
http://hartvilletool.com/product.php?search_id=10138
any thoughts….
Oh, I would be clamping a stainless steel screen to the bottom exit to keep varmits out.
Replies
I hope that you know you are playing with fire. Also, if any bad results(fire,explosion,etc) were to come of this venting revision, your warranty AND fire insurance could be voided. Just a thought. Hube
" AND fire insurance could be voided"
Prove it.
For years I have been seeing statements that you need to do this or not do that, usually in terms of electrical work and/or inspections.
But I read my policy and have asked others to find such terms and they can't. That included insurance agents and underwriters.
In fact I had one underwriter say that they covered "stupidity".
Now I am not suggesting that because of that I am recommend him make these modifications. In fact, without any direct knowledge of blower assited furnaces, I do have concerns about the back pressure that this would cause.
Did you notice that I said "could be voided" I did not say it "would be voided." Also,you would have to have X-RAY vision to see what is written into this individual's insurance package.
Can't do that. Ya need a slope to drain the condensate. Also can't exit the house within 4' of a window or door IIRC.
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
10'
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming.... WOW!!! What a Ride!
In NC it was 4..I know because we had to run it along the wall away from a door, till the deck got built..then we went in a joist bay, to the outside band.
10' makes more sense..but NC ain't known for common sense.
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
Flue outlet clearance from windows and doors is (i) 4' per GAMA, or (ii)whatever is spec'd by the manufacturer - saw a furnace the other day which called for a minimum 1' !
"It is as hard for the good to suspect evil, as it is for the bad to suspect good."
-- Marcus Tullius Cicero, statesman, orator, writer (106-43 BCE)
See, I did pass the HI test in NC..just forgot some things.
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
Lots of details to try to keep at hand!
"It is as hard for the good to suspect evil, as it is for the bad to suspect good."
-- Marcus Tullius Cicero, statesman, orator, writer (106-43 BCE)
I'm glad i have a photographic memory, But I need more film.
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
Or an OS that doesn't behave like Windows...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming.... WOW!!! What a Ride!
hmm.... I wish I could post a picture, the flues exit through a wall four feet off the ground and currently end as open stubs that go about one foot out of the wall. The pipes the closest opening to the pipes is the doorway to the boilers and the heater that is 8 feet away. (this is a seperate room attatched to the main building) I was wondering if it is ok to route the exhaust from horizontal to vertical (down) after it has left the building.
Edited 7/18/2004 4:15 pm ET by jrobbins
I don't see why not except for the fact that THAT leg could still get condensate and freeze..drips like icecicles, and lead to a blockage.
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
Slope back to the unit for condesate draining and jump the whole thing to 3" rigt from the get go and still turn down if you like once yur outside...
If you slope to the outside it will ice up and plug solid...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming....
WOW!!! What a Ride!
J,
Have you actually had an HVAC person look at the furnace ?? If it is vented through a 2" pvc pipe, that means it is a High Effeciency unit with a draft fan. It really should be silent when it first fires up. It almost sounds like the igniter is not working properly and allowing a build up of gas, and then a sudden ignition which makes the "whoosh" sound. Our old oil burner used to do the same thing when it was getting dirty. Our high efficiency gas furnace makes no noise at all other than the sound of the draft fan motor. Might be worth it to have someone look at it.
Just a thought,
Bill Koustenis
Advanced Automotive Machine
Waldorf Md
this is at my friends place, and it the exhaust pipe is only about 3.5 feet long, it comes on and maintains a wooshing noise that drives his neighbor bonkers. I will try to shoot and post pictures.
Go to 3"... Turn it down like you want.. Be mindful of the slope...
AND....
Open the fan and see if there has been a restrictor left in on the intake side of the blower.. It may look like a reducing washer... If so remove it...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming.... WOW!!! What a Ride!
Bill is absolutely right. You need someone trained to look at it.
Senior moment for me, I was reading this as some form of water heater.
Where is the "woosh" coming from? The flue or the burners?
Are the burners enclosed in a metal box (likely with 1 little round viewing window) or can you actual;ly see and touch them?
Are there dark stains or burn marks above the burners?
Is the draft inducer coming on before light-off? The draft inducer should be preventing any accumulation of gases at the ignitor, but I don't think the ignitor is supposed to light on any models unless the draft has been proved by pressure switches.
Are they "in-shot" burners - the flame shooting out of a cylindrical burner "jet" into a round tube?
Each manufacturer and model has specific instructions and requirements for the flue installation
If you screw around too much, you can cause big time carbon monoxide problems.
"It is as hard for the good to suspect evil, as it is for the bad to suspect good."
-- Marcus Tullius Cicero, statesman, orator, writer (106-43 BCE)