Tjernlund LT4 Lint Trap for DEDPV Dryer Booster Fans

This unit does an excellent job of collecting the large amount of lint that passes through the dryers internal lint screen. I would recommend using hvac (Not gray duct) tape to seal all seams inside and out as to prevent lint from catching on the sheet metal edges. The inlet and outlet are also the same diameter, so it is necessary to use a coupler when connecting the output side to rigid 4" tapered metal ducting. I also fabricated a bracket out of a piece of aluminum to secure it between wall studs rather than relying on the ducting itself to support the unit in the wall cavity. The unit seals well. It does get a bit warm to the touch when the dryer is running, but there is hot air passing through it, so that is to be expected. It never reaches a point where it cannot be touched though, and removing it while dryer is running is not the brightest idea anyway. When used in conjunction with a booster fan, this helps eliminate clogging and fire hazards due to lint buildup. I ran this unit without a booster for about 2 weeks before getting around to installing a booster and it had no adverse effects on dryer performance, and when I did open up the new ducting I installed after those two weeks, there was virtually no lint in the 4" rigid ducting over a 25 ft run. I am using this unit now in conjunction with a fantech booster installed approximately 8 ft after the trap unit. It does appear that the suction created by the booster is making the screen in the unit a bit more "flexible" than it was before the fan was installed, so time will tell if the screen holds up. Overall a great addition to control lint and protect from a potential fire.

This lint trap was required by Code (The inspector let us know early on) since we needed a booster exhaust fan (also Code required) because of the length of the duct. The first time we used it, we understood the reason for the Code requirement. There was a bunch of lint the dryer lint filter missed. I guess I shouldn't be surprised. My old house always had lint around the dryer vent outside. You certainly don't want all that lint plugging up your booster fan and having to try and clean it out. This was a good long-term investment. I'm not super impressed with the seal between the door and the wall, but the booster fan is probably creating a slight negative pressure. I see no signs of lint building up around the door (on the wall)The filter housing is very sturdy. It has a clean look on the wall too. I don't recall if we had to "crimp" the exhaust side to fit inside of the next length of pipe, but a stove pipe crimper works well. YouTube also has videos on how to do it with other tools.

Easy to mount, easy to clean

I used this to set up a long running dryer vent. Our new overly sensitive dryer kept shutting off early and I realized it could not push the vented air 15 feet to the outside of the house. So, I had to put an additional blower in place to assist. I put this filter box close to the dryer to keep lint from building up in the assisting blower. Every work correctly. The additional vent blower is temperature controlled so when the temperature rises, the blower turns on.

Living in temporary quarters for a bit while trying to find a house, the dryer was 25' of serpentine ductwork from the nearest access to the outside. Installed a steel flapper duct door, high quality ducting, and a current-activated booster fan. Installed this filter box between the dryer and the booster to catch any debris that might have gotten to the booster blower. Astonishing how much lint it collects that gets past the dryer filter! Very easy to use. Heavy duty. Solidly built. Quality. Easy to install. Clearly very useful, keeping TONS of lint from clogging up the booster fan blades!

This item is not manufactured to the highest of standards. The box is not square so the door appears crooked when assembled. (see picture). I had to remove the handle and screen, rotate clockwise and screw back together so the door would be straight. Also, if you have a gas dryer you'll definitely want to apply heat resistant foam insulation around the edge to prevent CO from escaping into the room. For those of you who don't have access to the wall behind your exhaust pipe, like me, I mounted the box behind the dryer using 8" L-brackets. That way I didn't have to tear open the drywall and then repair it after installation. Overall, this item does capture lint that the dryer missed so it does its job. You may need to do some modifications before you install yours.

I liked how it looked at first glance but upon handling it and inspecting it caused me to dislike it. Most of its edges were very sharp to the touch and required deburring. The lid could've been designed with a better securing system to the box like a manual latch or with magnets. It also lacks seals to make it leak proof. With the screen fully seated inside this box, there was a 1/4" gap that could allow lint to pass underneath. Both 4 inch ductshave weld flanges, but one is welded to the outer side of the lint trap and had a gap that needed to be sealed. Again, nice concept and has potential but this one is poorly designed and lacked good workmanship.

100% needed for all homes!! Brand new house, dryer collects a ton of lint but this collects just as much. It’s insane how fast it fills up! Wife forgot a few loads and it was over flowing. I can’t believe how bad your ducts could get in just a short amount of time!!! I still give 5 stars but like most have said, the door goes back in and can be a little crooked. You have like 1/8-1/4” of movement from perfectly level to a little left side lean. I don’t care though, you can get it level and it’ll stay and it’ll 100% save your ducts! Dryer! And no house fires!