Connecting duct for range hood vent

UAL767 · 01-28-2010, 10:49 PM

I'm trying to extend an older range hood exhaust to a vent on the roof. I have a transition from the 3 1/4x10 to 7" pipe that has a simliar connector as shown in the picture. I can't seem to figure out how to connect the transition to the existing 3 1/4x10 shown in the picture. Any help would be appreciated.

ricky82g · 01-29-2010, 08:28 AM

maybe a slip and drive connection. is the joist in the way or is that an illusion?

UAL767 · 01-29-2010, 09:40 AM

The joist is in the was a little, but I can move it up enough to get tape on it. I originally thought I could just force fit the connections together and tape, but the connection doesn't appear secure enough without a mechanical fastener. Does this type of connection require screws? I've included better pictures in the link: http://home.comcast.net/~ghostrider560/vent.htm

Thanks

hvac122 · 01-29-2010, 09:57 AM

Most 3 1/4 fittings are for buttonlock fastining. You would need to get a buttonlock tool and use it on the duct comming up. Then the boot would snap to the duct and be sealed with good quality silver tape.

I couldn't tell from the picture if you had a end boot or a strait boot. Looks like you would need a end boot to miss the joist.

UAL767 · 01-29-2010, 10:23 AM

http://home.comcast.net/~ghostrider560/vent.htm These are better pictures of the to sections of duct I'm trying to join - If you could look at them and see if it is a buttonlock or a "slip and drive" both joint ends appear to be the same type may need an adapter.

hvac122 · 01-29-2010, 11:22 AM

The existing duct looks to be a buttonlock fitting. The boot, when I enlarge it, gets to blurry to see. If you could remove the ends on the boot then you should be able to buttonlock it and snap it into the duct.

Your correct that they are both the same on the ends and will most likely not go together that way. Remember not to skrew any of the joints.

UAL767 · 01-29-2010, 11:33 AM

The ends of the boot were pinned on so I should be able to drill them out and do as you recommend. Thanks for the advise. I'll let you know how it goes after this weekend.

profiler1 · 01-29-2010, 03:12 PM

Hi. Just pickup an end boot (5" or 6") diameter from the hardware supplier for that size. If you don't have a drive bender or know how to, simply use another couple of S cleats (cut them about 1/2" to 1" shorter) and slide the boot into the cleats. Drill 1/8 hole where you can in the middle of the drive in both ends or sides which ever you can (4 is plenty) then use a no. 8 or so metal screw or wood screw will work. After its fastened, take some metal tape and wrap it. Connect to the round duct and your done.

hope that helps. Marcel.

hvac122 · 01-29-2010, 04:18 PM

Quote:

Originally Posted by profiler1

Hi. Just pickup an end boot (5" or 6") diameter from the hardware supplier for that size. If you don't have a drive bender or know how to, simply use another couple of S cleats (cut them about 1/2" to 1" shorter) and slide the boot into the cleats. Drill 1/8 hole where you can in the middle of the drive in both ends or sides which ever you can (4 is plenty) then use a no. 8 or so metal screw or wood screw will work. After its fastened, take some metal tape and wrap it. Connect to the round duct and your done.

hope that helps. Marcel.

It is against code to put skrews in a range vent.

UAL767 · 01-31-2010, 02:18 PM

HVAC122, you were right on with the buttonlock connection - after drilling of the connector on the boot it was easy to see how the joints went together. I also used a 1/4 chisel and punched 3 button locks on both of the longer sides of the boot. I was surprised to see how secure the joint was after I put them together. Silver tape to seal it up and confident that it will last for a long time.
Thanks again.