Replies

1. 
   rlrefalo | Mar 16, 2008 03:00am | #1

   Steel duct is best IMO. Less concern about fire.

2. 
   Riversong | Mar 16, 2008 03:06am | #2

   If it's a gas drier, you have to use steel ducting.  Avoid flex duct as it creates too much turbulence and backpressure.

   Why are you using two elbows and making such a long run?  Keep it short with as few turns as possible to get good flow and prevent lint clogging the system (which can also be a fire hazard).

    

   Riversong HouseWright

   Design *  * Build *  * Renovate *  * Consult
   Solar & Super-Insulated Healthy Homes
3. 
   Pelipeth | Mar 16, 2008 03:07am | #3

   Here in NY it's against code to use PVC. My plumber tells me it will melt from the inside and seal up. I believe your stuck with galvanized or aluminum pipe. The newer dryers can get extremely hot also and the ones with steam features create ALOT of moisture so be sure to pitch the pipe properly. PS. U do have alot of 90's

   
   

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   Edited 3/15/2008 8:10 pm ET by Pelipeth

4. 
   Dave45 | Mar 16, 2008 03:11am | #4

   Whatever you do, don't use the plastic flex vent hose.  Four inch round metal will work fine as long as you:

   • keep the run as short and straight as possible
   • try to use sweeps instead of elbows for your turns (a sweep is just an elbow with a longer radius)
   • make sure that any joints are pointed in the right direction (the inside part of the joint is on the uptream section)
   • don't use sheet metal screws - they act like little lint traps
   • build it so it can be easily removed for cleaning.  When my daughters were still here, I had to clean my vent line (10' no turns) every 12 - 18 months.  I haven't had to clean it since they've been gone (five years), but it's probably time to clean it again - a load of my jeans and flannel shirts is taking longer to dry than it used to.
1. 
   whals | Mar 16, 2008 03:39am | #5

   Sorry I did leave out a few things. I live in NY, it's an electric dryer, and the reason for so many 90"s is it is by an outside wall. On the otherside of that wall is a crawl space for my kitchen so I have to make a few turns to vent it out so it is not under the house. Thanks for the help.

1. 
   Riversong | Mar 16, 2008 03:52am | #6

   Then move the drier. 

   Riversong HouseWright

   Design *  * Build *  * Renovate *  * ConsultSolar & Super-Insulated Healthy Homes

5. 
   MSA1 | Mar 16, 2008 04:22am | #7

   No to PVC. Its a fire hazard. Having said this my old house had PVC fr over ten years.

   I recently turned it into a rental so I removed the PVC and installed the required rigid metal (use metal tape on joints not screws).

   The PVC I removed was completely covered in lint. The whole run about ten feet.

    

6. 
   DanH | Mar 16, 2008 05:47am | #8

   Don't use flex for dryers. Ever. It collects lint inside like you wouldn't believe.

   The aluminum, snap-together vent pipe is what's used for 90% of installations, and it gives perfectly good service. Just be sure that all sections of the pipe are accessible somehow for cleaning.

   If your view never changes you're following the wrong leader