Extra Dryer Venting Needed

[NJ Jon]

I've got a couple of dryer stacks I can only use one pocket on due to insufficient venting. I want to get all the dryers on line, but poking more holes in the building may be a problem.

A friend suggested I use a commercial venting unit that has a fan motor to help push the waste air out of the building. I have some reservations about this, but figured out the best place to get straight information is right here.

Has anyone used one of these exhaust venting units, and what has been your experience? Any comments about creating a low pressure area inside the mat, make up air, cost versus benfit, etc, etc? If you install one of these fans, do you still need the full recommended vent size?

Lots of questions, and I don't know the answers.

Thanks,


NJ Jon

[laundryboy]

You don't want to extract air from inside the building. You want to increase air into the building.

Were you thinking of reversing the installation such that the venting will blow into the building?

[NJ Jon]

Laundryboy -

I know I'll have to get more make up air from somewhere, and there may be a couple old building vents I can convert. If I have to go to powered input air to compensate for power venting, then I can see this project spiriling out of control very quickly.

All venting will go outside the building, I don't intend to recycle warm moist air back into the building.

I'm hoping someone has installed one of these powered venting units and can give me the benefit of his / her hard won experience. Checked the search engine here on the board, but didn't see anything directly on point, hence my query.

NJ Jon

[MSKLAUNDRY.]

Since you didn't say how your venting is run right now and how many dryers are attached to it, it is hard to tell you what will work and what will not work. Please describe what you have in place now.

[MSKLAUNDRY.]

Be very careful if you choose to use a power vent. I had a semi hi- rise upscale residential building here is Manhattan using one of those to pull/push the dryers air up to the roof which was over 20+ stories. The unit was a monster and when it came on is would compress the venting as is sucked the air right out it. It worked fine for over a year until a fire happened in one of the Maytag stack dryers. It turns out that the motor on one of the Maytag dryers stopped (failure). Normally the air flow switch would turn the gas off since the motor was now off. But in this case the suction from the power vent was so strong it would pull the air flow flap in even when the dryer motor wasn't running.

So be careful.

[NJ Jon]

MSK -

Right now there are eight stacks and four singles all feeding into a single plenum chamber venting out the side of the building. Wall opening is about 3 feet by 3 feet. Not my design, it's been there for awhile, but seems to work as long as only half the dryers are on line. More than that and clothes don't dry.

I can run about ten feet to another part of the wall for additional venting, but if I do this, I won't have any "rise" in the ducting - it will all be horizontal. This pretty much leaves the roof, but I don't want to make any more holes there than necessary.

That thing about the fire in the highrise scares me. I definitely don't want to create that type of hazard.


NJ Jon

[MSKLAUNDRY.]

For starters what is wrong with running a horizontal vent with no rise?

If you can run another line horizontally out the side of the building I would do it that way. Why make it harder than it has to be.