Author Topic: Holding tank vent  (Read 117 times)

Scott

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Holding tank vent
« on: June 05, 2020, 04:29:01 PM »
I have converted the starboard water tank to a holding tank and was wondering if anyone could tell where the existing vent goes to, and also some ideas with regard to venting the now holding tank to the exterior of the boat. Thanks, Scott

Scott

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Re: Holding tank vent
« Reply #1 on: June 27, 2020, 08:32:09 AM »
Is there anybody that can tell me where the vent to their holding tank exits their boat ? Mine did not have a holding tank so I would like to know where best to have the vent exit to the exterior before I go to cutting a hole in the cabin top or topsides. This newbie just wants to be sure before making that leap !

Dolce_Vita

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Re: Holding tank vent
« Reply #2 on: June 27, 2020, 02:10:19 PM »
Ours exits through the hull, on the starboard side, just below the toe rail and ahead of the chainplates.
@(^.^)@  Ed
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with rebuilt Atomic-4

Last Resort

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Re: Holding tank vent
« Reply #3 on: June 28, 2020, 10:48:59 AM »
my existing tank in the V-berth area vented out behind the Head cupboard. I wanted to add a 2nd one to vent in and produce better air flow with one taking air in and 1 taking it back out, so I just got the right size hole drill and went through the hull beside the original one. No issues.  FYI, the bigger you can go, the better. I ended up with a 5/8" hose for the 2nd one, but still have all the parts for a 1" that I had planned to go with, but changed my mind :)

Dolce_Vita

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Re: Holding tank vent
« Reply #4 on: June 28, 2020, 12:42:57 PM »
The more venting the better.  Its the anaerobic bacterial processes that produce the bad odors, so the more air (and thus more aerobic decay) the less odor.

A good place to put a second vent (though harder to route) is on the opposite side of the boat from the first one. This provides more air circulation by taking advantage of the pressure differential between the two sides of the boat whenever the wind isn't exactly head-on or stern-on.
@(^.^)@  Ed
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Scott

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Re: Holding tank vent
« Reply #5 on: June 28, 2020, 09:08:37 PM »
Great, just what I needed. I love the idea of a vent going to either side. Thanks, Scott

Alma

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Re: Holding tank vent
« Reply #6 on: June 29, 2020, 12:38:14 PM »
My starboard water tank vents in the cabin!

You'll want a large diameter vent that goes outside.

As Ed recommends the larger the better. Some yachts have 1.25" vents!

You'll want the ability to backflush the vent from outside into the tank (with the pump-out cap removed) should it ever get clogged.


If you're sailing past Cape May give us a shout-out!