Vent line routing

[dsteinfeld]

Hello Peggy,

A number of years ago I replaced my aluminum holding tank with one from your company. The tank itself is fine, however the vent is clearly not working. The tank is located under a settee, equidistant from bow and stern. The vent line runs to the stern (~20'), so this is clearly no good. Can I run a new vent line straight up from the tank (the fittings are almost against the hull), with a 90degree open thru-hull right below the toe rail, or is vertical a no-no? I noticed in other posts you mentioned that a single vent line handles 90% of the cases. What are the other 10%?

I've seen your recommendation of the Sweet Tank system, but I'm afraid I'd need to install a solar panel as New England weather sometimes keeps us from the boat for a few weeks...

Many thanks!
Doug

 

[Peggie Hall HeadMistress]

I sold my company in 1999, so if you bought the tank from me

It was more than 12 years ago...you've lived with that vent line for that long???

To answer your question...yes, you can install a new larger vent line in a different location. However, I wouldn't go straight up...I'd go forward far enough to keep the vertical rise to no more than 45 degrees. I'd also install a new vent 1.5" vent fitting on the tank (MUCH easier to do than it used to be, thanks to a li'l doodad called the Uniseal UNISEAL ) preferably ON the top of the tank, away from the hull, closest to the centerline of the boat...to prevent waste from spilling out the vent when the boat is heeled. I'll help you work out the details for all this one-on-one if you'd like to send me an email (EMAIL, not a PM, please!)

I noticed in other posts you mentioned that a single vent line handles 90% of the cases. What are the other 10%?

A single vent doesn't work in the other 10%. :dance:

There is no one-size-fits-all solution...'cuz every installation is different, in a different location in the boat. Sometimes it only takes a 2nd vent line to create some cross ventilation...sometimes some mechanical intervention--Sweetank or two vents and an exhaust fan in one of 'em--may be needed. The right solution is case by case.