Thread: HVAC ducting question

Came across this the other day and I don't know what they are there for. Stainless sheets cut with tin snips and bent to form a louvered hood at the boiler and hot water heater vent elbows. What purpose does this serve? Never seen it before.
Thanks.

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Originally Posted by Scot Asher

Came across this the other day and I don't know what they are there for. Stainless sheets cut with tin snips and bent to form a louvered hood at the boiler and hot water heater vent elbows. What purpose does this serve? Never seen it before.
Thanks.

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Hi Scot,

The metal pieces were added to try and capture heat from the vents .
( aka free , recovered or recycle heat from the vent gases.)

Too bad they drilled holes ( not allowed ) in the vents as now they need to be replaced.
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Screws are required for single wall vent connections, so I don't see why it's really an issue having more screws penetrating the vent elsewhere. Very oddball set up though.

Billy, do you have a cite/source I can check out in regards to screw holes not being allowed?

thanks.....

Very strange and prob.not that affective.
Thanks Billy

Originally Posted by Brandon Whitmore

Screws are required for single wall vent connections, so I don't see why it's really an issue having more screws penetrating the vent elsewhere. Very oddball set up though.

Billy, do you have a cite/source I can check out in regards to screw holes not being allowed?

thanks.....

Brandon,

I think more on the lines of Manufactures Installation Instructions and the manufacturer allowing additional holes drilled into their vents ( along the 90 ) or elsewhere other than specific locations at the connections.

Do you have Manufactures Installation Instructions Allowing additional holes?
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If the screws are intact; then there aren't any holes...

Originally Posted by Darren Miller

If the screws are intact; then there aren't any holes...

There will be when you remove those " Heat Recovery Units " not alowed by The Manufacturer.
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Unless he reinstalls the screws in the holes.

Originally Posted by Darrel Hood

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Unless he reinstalls the screws in the holes.

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If those holes are allowed by The Manufacturer.
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or if your going to prescribe The Fix." https://www.buymightyputtynow.com/?rtag=mightyputty&

Billy,
I didn't intend to do either. I just observed that if the screws are reinstalled, there will be no open holes.

Originally Posted by Darrel Hood

Billy,
I didn't intend to do either. I just observed that if the screws are reinstalled, there will be no open holes.

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But there are holes.
* drilled, filled maybe OK, ( I would call it out. )
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- No 12" rise on flue before an elbow
- heat baffles were probably installed to keep the heat from melting the pipe insulation, and scorching the ceiling above the 6" flue pipe, ceiling looks like masonite or related wood core / cardboard product
- I vaguely remember some standard or guideline about that pipe insulation having to be a certain distance above the top of the water tank
- tank flue tees into boiler flue instead of a Y connection, with that goofy offset elbow on the water tank flue I would guess there's some back draft when the boiler is exhausting
- nobody wakes up one day and decides they are bored and thinks the best use of time is to install that crap, therefore assume that there has been a problem in the past and this is the supposed fix. Problem was likely heat.
- did you check the chimney for drafting or a liner?

Metal Tape Repaired Hole on left bottom side of vent.
* large screw needed to plug apr. 1/2 inch hole.
** screw plugged hole = No Hole.
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