Dryer vent cap
I am currently researching into dryer vent caps that provide an air-tight seal. I am aware of the Ecovent, the Seiho RCC-S with back-draft damper, and the Heartland products. I came across another product manufactured by a Canadian company, Dundas-Jafine Co., their ProShield(TM) telescopic dryer vent hood. I like this idea of having the air flow push out the vent and at the end having it pulled back to close, and the whole assembly is rather unobtrusive and not sticking out from the wall. You can view this vent hood at
The Heartland seems to generally get favorable reviews. I don’t find much information out there about the ProShield. Does anybody have any input or experience with the ProShield, or with the Seiho product for that matter? How air-tight are they in practice? We are not talking about a passive house application but the home is being built to the Canadian R-2000 standard on Vancouver Island, BC, so insulative value and air-tightness is an important consideration. Many thanks.
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Manfred ... I too have been researching back draft controls, dampers and venting solutions lately and want to use only passive solutions if possible on my house. Once thing for sure, dryer ventilation should not be done using the aluminum foil/wire helix exhaust piping ... the fire dangers and the dyer performance disadvantage are obvious.
A semi or full rigid exhaust will hold its shape and has much less inner wall friction (i.e. stopping lint, turbulence, kinked on bends, squashed by the dryer, poorly attached at either end, etc). The Dundas Jafine vent cap you pointed out seems to be the best so far, thanks. It is passive pressure-driven damper that keeps out the critters.
I wrote to Dundas Jafine about it and their product development manager replied:
"The ProShield is designed to open with 50 cfm using a 4” diameter duct. Most dryers push over 160 cfm, which is more than enough to fully open the vent. The spring used in the ProShield is made of stainless steel and is rated at > 1 million cycles.
The ProShield is designed for easy cleaning. The front of the vent opens to provide access to the duct. The vent itself does not get removed and the spring mechanism is never opened. That design will allow for regular maintenance without sacrificing reliability or reducing the life of the vent."
Match this with a semi rigid or even better, a rigid vent tube, and the pressures should work the damper without any problem. I would not trust that any damper will work properly when connected to the dryer by an aluminum foil, floppy, sloppy, high friction/turbulent flow tube.
IMO if you can install your dryer against an exterior wall, and go straight out with your duct, you'll be fine--the duct and the damper will stay mostly free of lint because the air velocity will be high, and the damper will open fully. I use a dryer box, a short length of aluminum flex, a rigid 90, and about 4" of rigid pipe for the typical install. I like the Seiho caps a lot, they are fool-proof. The DJ product mentioned in this thread looks pretty good too, but white plastic is less desirable. I guess you could paint it.
No queation the Seiho products are classy.
Many can be seen here: http://www.hvacquick.com/products/brands/Seiho
I need to hold 'em in my hands before I decide.
But the DJ products are UV treated plastic, can be painted, and most importantly they are plastic. I used to diss plastic in principle but lets face it, its less maintenance than other materials, can be made with additives to tolerate the sun and can be made to handle heat and cold. Unless I am worried about fire ratings, the plastic components in exhaust and make-up air systems have one very important feature: plastic does not have a condensing problem.
PS I forgot to mention "critter stop". The DJ model, for example, has a full circumference, spring operated, jambing baffle, not a swinging (louvered) gate. Where I am, critters of all sorts will be able to access the dryer vent through a louvered back draft when its not in use. The DJ and other models Seiho models seem to more critter proof than the SB Seiho model in the photo.
Thank you for all your input indeed. I am still undecided between the options.
Oak, the info you received from DJ is very interesting, I had called them myself earlier and all the info I could elicit was that they don't have data to the required air flow/pressure and that there won't be any problems with duct lengths of up to 8-10 ft. According to the dryer manufacturer the flow is 131 cfm so it should be fine with the dryer against the outside wall and the minimum of straight duct length required. And yes, critters could be a problem here too especially with the vent being fairly close to the ground.
David, the picture is appealing but I can't correlate it with any of the Seiho products I find. Do you have a model number or similar information?
Many thanks, David.