holding tank vent lines

Status
Not open for further replies.
B

Bill

My holding tank under v-berth has two vent hoses connected on opposite sides of the tank, but the two lines are tee-d together and a single 5/8" hose run to a thru-hull fitting on the stbd side of the hull. This doesn't seem to ventilate the tank well...i.e. some odors in the v-berth. I'm planning to add a second thru-hull fitting on the opposite side of the boat and run two separate hoses to the tank in order to get some cross-ventilation. How high above the tank should the vent-fittings on the hull be? Also, does anyone know where I can find low-profile (preferably white) thru-hull fittings with 5/8" tailpipes? The ones that came with boat are 1" high black caps with an double wall opening on one side. They tend to snag the spinnaker sheets when we race. Thanks, Bill
 
Dec 2, 1997
8,959
- - LIttle Rock
If you really want to do it right...

First, test ALL your hoses for odor permeation, 'cuz how your tank is vented has nothing to do with odor inside the boat, only what belches out the vent thru-hull. The most likely source for the odor near your tank is a stinky tank discharge hose and vent hose(s). But you're right that teeing two vent lines together doesn't do much prevent odor out the vent. However, depending on where the thru-hull is located on the hull, where the vent fitting on the tank is located, and how long the vent line would be, you may not need two vent lines...one may be enough. When I have that info, I can tell you how to run the new vent(s). As for flush through-hulls that won't snag your spinnaker, swap 'em out for marelon open bulkhead fittings.
 
B

Bill

more on holding tank vents

Hi Peggy, I replaced the inflow/outflow hoses to my holding tank a couple years ago with the Sealand Odorsafe hose (pricey stuff). The tank itself is a roto-molded rectangular box with inflow and outflow on one end (intake above, outflow below). The outflow goes to a Y-valve which connects to a manual whale pump on one end and a deck pumpout fitting on the other end. I also have Odorsafe hose between the whale pump and the thruhull. The tank vent fittings are connected to a thruhull on stbd topside using 5/8" Trident XHD sanitation hose. The biggest problem is that the holding tank is only 13 gallons and on several occasions its overflowed out of the vent...probably causing blockage. I want to add another thruhull on the port topsides to remove the T and have two separate lines. I'm wondering how high above the tank I should route the second line. What angle should it be sloped to allow drainage in case it does overflow? Thanks, Bill
 
Status
Not open for further replies.