New Solar Vent

After about seven or eight years, my trusty 4” Nicro (Marinco) Day/Night Plus solar vent finally quit. No amount of resuscitation in the form of new batteries would make it run again. For some time, it has been getting slower and slower, and it finally stopped running even in bright sunshine. It was time for a replacement.

I bought a new Marinco 4” Day/Night Plus solar vent, but the design has substantially changed. The old vent was comprised of a separate base which was attached and sealed to the deck, and the fan/motor assembly attached to the base with three screws from the top. The new vent has a base that is actually a threaded deck plate that is attached and sealed to the deck, and the entire fan/motor assembly rotates down like a giant machine screw until it’s tight against the deck with a gasket in between. It’s a bit of an odd setup, but I was willing to give it a shot, especially since it has some new features the old one didn’t have, like a switch to reverse fan direction from intake to exhaust (as well as a shut-off) and even a small LED light..

However, when I bought the new 4” model, I found the outer diameter of the vent was a full inch bigger (10”) than the old model (9”), and I was shocked at how much of a difference one inch made. The new vent looked absolutely enormous, and the amount of real estate it took up on the foredeck seemed silly. Here’s a picture of the old vent compared with the new.

So, I returned the 4” and went with the smaller 3”, which has the same 9” outer diameter of the old model. While the 4” vent is supposed to move up to 1,000 cubic feet per hour, the smaller 3” vent can move up to 800 cubic feet per hour, and I can live with the difference. Unfortunately, though, it meant having to close up some of the hole in the deck since it was previously drilled to 4.5” and it needed to be only 3.75”. But first, I needed to remove the old vent, no easy task.

After unscrewing and removing the motor assembly from the base (easy), I had to detach the base from the deck (hard). Using a putty knife, scraper and other tools, I ended up breaking the base apart before it would finally come out. I then used the scraper to remove all the old sealant using rubbing alcohol.

Sealing the hole from inside the cabin with wax paper taped to the underside, I mixed epoxy thickened with fairing filler. Making sure to wet out the area first with unthickened epoxy, I glopped the mixed epoxy all around the hole, smoothing it out as best I could, realizing I would sand away any high spots once it cured. The next day, I did just that using sandpaper tacked to a block of wood, then marked the new 3.75” hole and cut it with a jigsaw. I’d say it came out pretty well!

From there, it was a very straight-forward installation of the base, drilling pilot holes for the screws and using 5200 sealant around the screw holes and base. Then, setting the large gasket in place, I screwed the whole fan assembly down into the hole until it was nice and snug. Done!

I’ll be using a lot of this article to update my Ventilation project page, so stay tuned for that to be reworked a bit. I’m hoping this vent will last for a while, and only time will tell whether or not it was a good investment. But, if it works as advertised, it should really help to keep ORION’s cabin mildew-free. Let’s hope it does its job!