Please help with noisy exhaust vent (with pictures)

[sbkim]

Hello all,

Thank you so much for the wonderful forum. I have been reading through several posts relating to this issue but I wanted to ask the forum specifically about my problem.

I recently purchased a new home and it has new Goodman HVAC. I presume this is HE unit but I am not 100% sure. The model number that I wrote down (CAPF3636C6BA) doesn't seem to register anything. The unit has two vents exiting to the side of my house (see pictures below). Unfortunately, my neighbors house is only about 10ft away and the exhaust vent noise is echoing back towards my bedroom window causing annoying high pitched whine. I called Goodman and they were clueless.

Here are my questions:

1. Is the intake and exahuast vents installed properly - the left is the intake and the right pvc is exhaust? They are about foot away from each other and over a foot above ground. Furthermore, there is slight pitch so that condensation can drip back down to the unit. The larger pipe is vent for the waterheater.


2. Is there anything I can do with the exhaust vent - perhaps put a 90 degree angle as opposed to current 45 degree to minimize the noise?

Thank you so much



http://i131.photobucket.com/albums/p290/sbkim/IMG00033-20091118-0704.jpg



http://i131.photobucket.com/albums/p290/sbkim/IMG00034-20091118-0734.jpg


http://i131.photobucket.com/albums/p290/sbkim/IMG00035-20091118-0735.jpg

[gary_g]

The model number that I wrote down (CAPF3636C6BA) doesn't seem to register anything.

That is the model number of a 3-ton Goodman cased evaporator coil.

Take care.

[BaldLoonie]

Those pipes are just asking for recirculation and sucking exhaust into the intake!

Exhaust should elbow up and blow straight out. Intake should elbow up and turn 180° along the house and point down. Something should be done with the WH exhaust so it blows out more and not get sucked into the furnace intake.

They will transmit noise outside. Worry more about the recirculation to avoid furnace damage.

[sbkim]

BaldLoonie - thank you for reply - I am a bit slow here but can you help me visualize what correct exhaust and intake would look like?

Exahust - do I just remove the 45 degree angle so it comes straight out? Wouldn't this cause more noise. I am not sure what elbow up means

Intake - I am even more lost with this one. I thought you just need to have this angle down - perhaps get a 90degree elbow to point down?

Luckily the 45 degree elbow is easily removable on both intake and exhaust.

[sbkim]

That is the model number of a 3-ton Goodman cased evaporator coil.

Take care.

Thank you - I guess I need to find the model # for the heater.

[BaldLoonie]

How much snow do you get?

[sbkim]

I just moved to NJ so I am not sure but I presume no more than 7-8"

I also found this (see page 16-17) which shows examples of how to install intake and exhaust. Could I use a tee to minimize noise???

http://securenet.goodmanmfg.com/pdf/infoPdf/Lit/IO-299B.PDF


http://i131.photobucket.com/albums/p290/sbkim/Picture1.jpg

Thanks so much!

[Gunnery Sergeant Hartman]

Hire a contractor to relocate the vent terminations to the other side of the house away from your bedroom.

[ampulman]

I just moved to NJ so I am not sure but I presume no more than 7-8"




If you're having the vents redone, you might want to have them 'elbowed up' as we do get some larger snow falls every few years, here in So. Jersey. With accumulations, you could be close.

If you're closer to NY, you tend to get a lot of storms that bypass us (Philly area).

The local TV stations are predicting lower temps and above average snow w/above average snow fall in Jan and Feb.

Amp

[sbkim]

Any thoughts on using vent flue tee as described above? Does this help with noise at all? Thank you!

[RoBoTeq]

Any thoughts on using vent flue tee as described above? Does this help with noise at all? Thank you!
It is possible that the Tee on the end of the exhaust, with the exhaust raised up and then back out, might dampen the sound a bit. The main reason to get the venting proper though is to prevent the flue gases from being recirculated into the combustion air tubing.

[Brian GC]

Any thoughts on using vent flue tee as described above? Does this help with noise at all? Thank you!

I am having the same problem with noise being generated between buildings from an exhaust. I can’t believe my HVAC Contractor didn’t realize the noise would be an issue because it is loud, especially at night.

After he told me exhaust ‘mufflers’ are not available I connected multiple PVC elbows and T’s to deflect the sound and covered it with a redwood box. Well, the neighbor is still complaining about noise. But think about it, sound travels through piping rather easily regardless of length or turns.

The only way to solve the problem IMO is to port it in another direction or to another location. My question is how long of a distance can 2 1/2” PVC be run in this application?

Brian

[sbkim]

Hi Brian - good to hear I am not alone but also sorry to hear that you are having this issue. My neighbor has not yet complained - luckily they sleep on the other side of the house. Based on what you are telling me, the noise really does not dissipate even with series of 90degree elbows and even with a box over it... doesn't sound like there is much else to do. I just want to muffle the sound so I don't hear the high pitched whine.

[wisconsinapp]

BaldLoonie - thank you for reply - I am a bit slow here but can you help me visualize what correct exhaust and intake would look like?

Exahust - do I just remove the 45 degree angle so it comes straight out? Wouldn't this cause more noise. I am not sure what elbow up means

Intake - I am even more lost with this one. I thought you just need to have this angle down - perhaps get a 90degree elbow to point down?

Luckily the 45 degree elbow is easily removable on both intake and exhaust.

What he is trying to say, is on the exhaust, your going to want to remove the 45 and put a 90 degree elbow on it pointing straight up, then on top of that 90, you will put a piece of pipe on it (in WI I usually go with and 18 inch piece of pipe, that way I know it will for sure be above the anticipated snow level,) then on top of that you are going to want to put another 90 degree elbow on it point straight out from your house so the exhaust blows out away from your house.



On the intake, you are going to remove the 45 and put an elbow pointing straight up, and put a piece of pipe in there, usually I go 12 inches, so I am lower than the exhaust and dont have to worry about re-circ, then put a 90 on top of that pointing to the left (away from the exhaust,) and then after that 90, you are going to put a street 90 pointing straight down to the ground, it will be gooseneck (in WI at least its know as it) and that is how they should be properly vented.

Best advice though, is if you have a house that close to you on that side, hire a heating contractor to come in, move them to a different side of the house, and they should know how to do that. Will have to spend some $$ but it would be worth it. I usually dont like putting my vent pipes in a tight area like that anyway.

[wisconsinapp]

I am having the same problem with noise being generated between buildings from an exhaust. I can’t believe my HVAC Contractor didn’t realize the noise would be an issue because it is loud, especially at night.

After he told me exhaust ‘mufflers’ are not available I connected multiple PVC elbows and T’s to deflect the sound and covered it with a redwood box. Well, the neighbor is still complaining about noise. But think about it, sound travels through piping rather easily regardless of length or turns.

The only way to solve the problem IMO is to port it in another direction or to another location. My question is how long of a distance can 2 1/2” PVC be run in this application?

Brian

To answer you question, it depends on the furnace. All furnaces are different, its in the installation manual. Usually you dont use 2 1/2 either, its usually either 2 or 3 inch. And as for the idea of multiple tee's and elbows with a redwood box, probably the worst idea I have ever heard of seeing as how each 90 is the equivalent of either 5 or 10 feet. So probably not too brilliant of an idea to do that.

[Brian GC]

To answer you question, it depends on the furnace. All furnaces are different, its in the installation manual. Usually you dont use 2 1/2 either, its usually either 2 or 3 inch. And as for the idea of multiple tee's and elbows with a redwood box, probably the worst idea I have ever heard of seeing as how each 90 is the equivalent of either 5 or 10 feet. So probably not too brilliant of an idea to do that.

Restriction was not an issue because one 2 ½” PVC pipe was divided into four 2 ½” outlets which reduced the volume of each outlet to one quarter. It was a better idea than my contractors, which was nothing.

Brian