"installing" in line fan- ???
 

I have a stove range hood that has is 360 cfm's, not enough for what I need so I purchased a 700 cfm inline fan. The question is this, when taking the "duct" that I put on the back of the range hood going out through the top of a window, I had only duct taped the vent pipe flush with the back of the fan. It worked!

The opening on the back of the range hood is a rectangle, about 2-3 inches tall by about 5 inches wide. The pipe and the opening didn't match-- hence, I duct taped it really well so the pipe laid flush against the opening.

Can I do the same thing for the in-line fan? Should I be using tin snips and cutting the opening wider on the range hood?

I miss my torch and want to set it back up this weekend. I'm giving up til spring on finding someone to pipe my fuel through the wall. NOBODY will do it for me- Dead River or Suburban Propane. I'm going to get some black outdoor tubing and put my hose thru that outside so the sunshine won't be degrading the hose and I'll put the hose back in thru the bottom of the window. Then I put pink insulation in the open top (for vent) and bottom (hose) of the window. Then I'll have some plastic put over the whole window to help insulate and weatherproof the window. It gets cold up here in my corner of Maine.

Not perfect by any means but it's what I can do for now. I keep a path shoveled to the fuel tank & always turn it off outside, burn off the fuel in the line and then go back outside to loosen the PA screw after I have burned off the fuel in the line. I'm as safe as I can be....

Input always appreciated but the major question is can I duct tape the inline fan to the flat back side of the range hood vent.

Thanks,

Sue

Hello Sue, What is the size of the opening of the in-line fan? I would think if the opening
on the back of your range hood and the outgoing pipe is not the same size, you would be decreasing the 700 cfm rating. No problem duct taping it all. How could we live without duct tape?
Jim

I haven't taken it out of the box yet but I'm guessing/assuming 5 - 7 inches? You're right, the rectangular opening on the back of the stove hood does NOT match the opening. I think I could take tin snips and cut the opening wider? I'll have to look inside the rectangular opening and see if it's boxed in or if opening the rectangle would make more open contact area or not.

I'll look when I go home for lunch.

Sue

Would I be better off asking my brother to make a plywood box with an opening on the back for the in line fan? The only real reason I have for the range hood one is the light that's built into the hood.

I can line the inside of the plywood box with aluminum foil as a barrier between the plywood and heat. It will take the temp. down a few degrees from heating the plywood.

I don't have the $$ right now to have a metal shop fabricate a box for me.

What are your thoughts?

Sue

Sue, I would work with the range hood, if you can cut it so it does not decrease the CFM of the fan. I do not like some, as they are too shallow. You can rivet or use some sheet metal screws to add some metal around it to make it deeper. I think that would be faster and easier right now for you.
Jim

Jim,

I have to admit I'd like to use the range hood if possible for 2 reasons. 1 is the light but 2 is the $$ I spent to have legs brazed to the hood to make it the exact height recommended for ventillation above the work area.

I'll take a look when I go home at lunch. Will try to post some pictures. Seeing would sure help people give me advice!

Sue

It will probably be best open up hood opening to match fan diameter if at all possible.... You may be able to get some adapter rings or something that will make it easier to attach fan to hood at hardware/home improvement store, maybe something that can be modified to create tabs the can be screwed to hood.....

As for "Duct Tape"... not a chance, its not the item you need for sealing... The adhesive will dry out on about 6 months and tape will begin to fall off.... Get regular "sealing tape for HVAC ducting" it is a aluminum foil back adhesive tape the is specifically designed for duct work. Ironically duct tape is not really good for sealing ducts..or much of anything else where you want permanency....

Dale

Speaking from experience. Be careful when using the foil duct tape on sharp edges/corners. If the edges are sharp you may want to file them smooth. I didn't and the sharp edges cut the foil tape, leaving holes for the fumes to escape back into my work area.

I agree with Dale - do not use "duct tape". The heat from the light can also make a sticky mess.

I was cheap and bought a cheap range hood. So now I am thinking about using an in-line fan too.

Hope it works for you.
cem

I agree with the others regarding cutting the opening from your hood to match the size of the fan. Otherwise, your fan will have to work harder to move the air and you'll burn it out. Also, use smooth ducting, not flexible.

The foil tape is very easy to work with and works fine.

-Diane

Thanks! I will post some pictures and I just learned something! I had never heard of the tape Dale mentioned but will be sure to use this with whatever I end up doing. I will keep you posted. I want this to be done right... I only have one set of lungs, eyes.. etc.

Better safe than sorry. I don't know why I have had such a hard time finding someone to pipe the fuel thru my walls but it has been discouraging. I've been without a torch for over a month now. Thank heaven for the Playing With Fire in Rockland but I want my own torch back for daily use. I'll just have to live with the hose thru the window til spring but at least now I know to put the black outdoor rated hose tubing OVER it to help avoid the sun. That's still a step in the right direction.

Sue

Sue,

I framed my own 'hood' out of 2x4's and then covered it with a combination of cement backerboard (behind the flame) and metal flashing (sides and top). After laying down the metal flashing on top (easy to cut to size with a tin snips), I added a 1/2 thick piece of plywood to support the weight of my fan. I used a jig saw to cut a hole the diameter of the inlet to the fan. My in-line fan has a 'shoulder' - the body of the fan is a little bigger in diameter than the inlet and outlet, so it rests nicely on the plywood with just the inlet sticking through. I was originally going to mount it this way (you might be able to, also), but ran into a problem with where I needed to take the exhaust ducting, so I have a 90 degree bend into the hood and then the fan mounted to the top of the plywood.

I made my hood a barley box style. It's basically an open-faced cube that sits on my workbench. It's extremely sturdy, and easily supports the weight of the fan. I don't know how to weld, so for me, cutting up lengths of 2x4's is easier, plus it's not too expensive (2x4's are $2-$3 each).

I once tried what you're thinking about - adapting a fan to a kitchen vent hood. Again, because I can't weld, I made a wood frame and screwed the kitchen vent hood to that. I had the same problem of trying to match the vent hood cut-out to the in-line fan. I cut out a circle about an inch smaller in diameter than the fan opening, and drew a circle around it slightly smaller than the diameter of the fan opening. I made cuts just to the outer circle all the way around, spaced about 1/2" apart, much like you would if you were putting a sleeve in the armhole of a dress. I then pushed these tabs up verticle and then slid the vent pipe over it (I had my fan mounted elsewhere). I then sealed the pipe to the hood with HVAC tape.

You can certainly make this work, too, but I found it was easier just to make a cube with a metal flashing/plywood top.

Linda

Hiya Sue! I'm glad Dale brought that up about duct tape! I use a lot of it too, but not on something like my ventilation.

Where you live, I would NEVER use duct tape in any type of sealant process!! The weather can get too harsh up there.

Duane
PS I can hear those cards shuffling now!

Photos:

from the front:



from the back



fan in box



writing on side of fan box



Does this help? Guess I'm looking for confirmation of advice given and welcoming all suggestions.

Sue