Dryer Duct Boosters?

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Anyone have any experience with these and have a preferred brand? The builder of our house (in his infinite wisdom) ran the duct from one side of the house to the other and it has one 90° ell and two 45°ells in it. A total run of about 27 feet. Though we recently had the duct cleaned and I went from electric dryer to gas, the drying times are still too long and I am guessing a booster will help with that.

Thanks in advance for your thoughts.
 
Find the Owners Manual for the Dryer.
See what the Manufacture recommends for venting / and what's not recommended.

I always figure venting should be as short as possible with least amount of bends.

Where is your Dryer located ?
How far from nearest wall ?

My Dryer vent goes out the side of house / UP and OUT - 10 Ft. total.
 
Originally Posted By: larryinnewyork
Find the Owners Manual for the Dryer.
See what the Manufacture recommends for venting / and what's not recommended.

I always figure venting should be as short as possible with least amount of bends.

Where is your Dryer located ?
How far from nearest wall ?

My Dryer vent goes out the side of house / UP and OUT - 10 Ft. total.
You are correct that venting should be as short as possible, but as the vent is installed I am not going to re-run it. In the current thought processes, the laundry room is centralized in newer homes to minimize steps, but that is not very conducive to good vent design. There is no outside wall to vent towards so it goes through the roof. The $100,000 question is why did it not just route above the laundry room and out of the roof instead of going across the whole house. I am certain with the 3 turns the calculated run is too long, but I did not build this house so I had zero input into that part. A booster is the answer, I just wanted input on brands in case there is one to stay away from or one that is known to work better than others.
 
27 feet is nothing. My dryer exits the rear into 90* downward through the floor, into another 90* for a horizontal run of 35 feet followed by a 45* upward angle into another 45* angle to go back to horizontal and into the exhaust flapper. 90* turns add the equivalent of I think 5 feet. My dryer manual said anything under 50 feet (straight runs & bends) was fine and has been. Our dryer is gas and located centrally as well.

I have a family member that put an auto booster fan inline and swears by it.
 
Originally Posted By: 04SE
27 feet is nothing. My dryer exits the rear into 90* downward through the floor, into another 90* for a horizontal run of 35 feet followed by a 45* upward angle into another 45* angle to go back to horizontal and into the exhaust flapper. 90* turns add the equivalent of I think 5 feet. My dryer manual said anything under 50 feet (straight runs & bends) was fine and has been. Our dryer is gas and located centrally as well. I have a family member that put an auto booster fan inline and swears by it.
27 + 10 then with the bends (if I have guessed correctly at the linear run). There is something to it because a neighbor with an older home has the same dryer with a 11 foot exhaust (straight) and his will dry in 1/4 of the time that I am experiencing and my dryer is fairly new and has been checked out. It also has the vent warning sensor and it comes on every time we dry and did from the first day, but I did not think too much about it until recently. I am going to have the duct roto-rooted again to remove the lint build-up and install a booster in the coming days and will see how it does.
 
You might try opening a nearby window and verifying there are no exhaust fans running (bathroom, kitchen, etc), and see if that makes any difference. Modern homes that are very tight will reduce airflow.
 
Originally Posted By: 2015_PSD
Originally Posted By: 04SE
27 feet is nothing. My dryer exits the rear into 90* downward through the floor, into another 90* for a horizontal run of 35 feet followed by a 45* upward angle into another 45* angle to go back to horizontal and into the exhaust flapper. 90* turns add the equivalent of I think 5 feet. My dryer manual said anything under 50 feet (straight runs & bends) was fine and has been. Our dryer is gas and located centrally as well. I have a family member that put an auto booster fan inline and swears by it.
27 + 10 then with the bends (if I have guessed correctly at the linear run). There is something to it because a neighbor with an older home has the same dryer with a 11 foot exhaust (straight) and his will dry in 1/4 of the time that I am experiencing and my dryer is fairly new and has been checked out. It also has the vent warning sensor and it comes on every time we dry and did from the first day, but I did not think too much about it until recently. I am going to have the duct roto-rooted again to remove the lint build-up and install a booster in the coming days and will see how it does.
Edit - I found some information online about the overall length of the duct and I just checked behind the dryer and I have two 90° bends in the flex duct so I have at least 42 calculated feet. My guess is the builder got away with it because they do not have to account for the flex duct:

Originally Posted By: Fantech
The 2012 International Residential Code (IRC) is pretty specific when it comes to dryer exhaust venting. The maximum length for dryer exhaust duct cannot exceed 35 feet from the dryer location to the wall or roof termination. Each elbow reduces this maximum allowable length by 5 feet since the restricted airflow that these fittings create is more than the same length of linear duct. Each dryer exhaust has its own specifications for duct length, so contractors should refer to these instructions, as well, to make sure the dryer duct length does not exceed a particular model’s capability. Given these restrictions, it is highly likely that dryers located in interior spaces will exceed either the IRC or the manufacturer’s limits on duct length.
 
Reading this I am lucky the washer/dryer in my house are against an exterior wall. The vent looks just like how someone would route an exhaust on a turbo drag car, just straight outside.

Learn all sorts of things on here. I will have to remember this for if I ever move and do home shopping.
 
Is your dryer duct 4" diameter?
Plumber put 3" duct under our concrete slab venting outside.
Plumbing inspector nor I caught it.
Never worked....
 
Originally Posted By: Bebop367
Is your dryer duct 4" diameter?
Plumber put 3" duct under our concrete slab venting outside.
Plumbing inspector nor I caught it.
Never worked....
It is at the wall connection. I have not checked in the attic yet. That would be a bummer and would result in new duct that I would not run the same way the builder did.
 
Take the hose off the wall and put a pantyhose on the end of it to catch the lint. Do a load of laundry and see how fast it dries.
 
Originally Posted By: Nick1994
Take the hose off the wall and put a pantyhose on the end of it to catch the lint. Do a load of laundry and see how fast it dries.
I doubt the pantyhose would last since it is a gas dryer, but that is a good idea.
 
Originally Posted By: 2015_PSD
Originally Posted By: Nick1994
Take the hose off the wall and put a pantyhose on the end of it to catch the lint. Do a load of laundry and see how fast it dries.
I doubt the pantyhose would last since it is a gas dryer, but that is a good idea.
In my grandparents previous house the dryer duct was clogged and my grandmother used a pantyhose for like 10 years, she'd just change it once every week or 2. It was an electric dryer but no issues. Even when doing 3 loads of laundry in a row.
 
Some roof vents can be very restrictive as well.

Here's a video of a guy testing different designs:

https://www.youtube.com/watch?v=47QHn-DFRcA

Although it'd probably be easier to put in a booster than tear up your roof

I hope you're using a semi-rigid aluminum flex tube behind the dryer instead of the Mylar and coiled wire variety or those sliding, low profile metal designs.
 
Originally Posted By: Fsharp
I hope you're using a semi-rigid aluminum flex tube behind the dryer instead of the Mylar and coiled wire variety or those sliding, low profile metal designs.
Yes; semi-rigid aluminum. Mylar would be a fire waiting to happen. Thanks for the information on the vent, but I think as you say the booster is the path of least work.
 
Well, I have a 32-foot run plus 2 elbows, and it takes 35 minutes to dry jeans not counting the cool-down phase. That's for an electric on medium setting. It's the same time as my parents whose dryer has a very short run. There must be something else causing your lengthy drying times. You compared your drying time with the neighbor's; but what washer are they using? Some washers wring clothes dry better than others due to a faster spin cycle.

But based on my own experience, the duct length isn't a big factor
 
Originally Posted By: xfactor9
You compared your drying time with the neighbor's; but what washer are they using? Some washers wring clothes dry better than others due to a faster spin cycle.
It is the same model washer and dryer; Samsung.
 
The Power Vent may well be the best solution.
Sounds like you already decided on getting one.
-----------------------------------------------
I like to go thru the REVIEWS on Amazon.
Some may be fake, but the Negative ones give you a heads up on any weak areas.

Check (I'm sure you do) the Lint Trap in Dryer. Clean after each use.

Also check - Once a year I pull the 'front' off of Dryer and vacuum around the Fan Blades.
It's amazing how much lint builds up besides just the Lint Trap.

Also check that the Vent Pipe is CLEAN.
With a longer run, you might have more lint build-up as compared to shorter run.
Sometimes I see clumps of lint outside underneath the vent exit (10 Ft. run).

As someone else said, is your Washing Machine spinning the cloths enough to remove excess water ? ? ?

If you have to add an electrical outlet for the power vent, know your Electrical Codes.
Only creates future problems if not followed.

Lastly, if your venting is not sealed correctly, you may be exposed to Carbon Monoxide (the Silent Killer).
I knew someone who died from that (heater in his garage).
If in doubt, install a Carbon Monoxide Detector in the area.

When I had a new Furnace install, they hard-wired a Detector in for me (Battery operated would be just as good).
Their idea, and a great one.
 
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