Author Topic: Holding Tank Vents on 44.5  (Read 355 times)

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bp919

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Re: Holding Tank Vents on 44.5
« Reply #5 on: August 03, 2017, 05:27:31 PM »
Steve ...replacing carbon filters will help that odor as well ... on H49-50, i've got carbon filters on each vent line - if HT overfills, carbon is wrecked and should be replaced ... Original filters were factory made (saniguard i think)... kinda pricey, so i made my own out of 2" PVC and Aquarium filter carbon)... Along with keeping HT's 3/4 full or less, this eliminated odor problem...

BP

libelo.lee@gmail.com

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Re: Holding Tank Vents on 44.5
« Reply #4 on: July 20, 2017, 12:28:18 PM »
Thanks Guys,
I found the vents and will be blowing them clean if I can figure out the easiest way to do that. I also realized that the tanks are far too small and fill up very quickly with the electric flush heads that the previous owner installed. I think my next step it to figure out how and where to install new larger tanks and to make sure the macerators are working correctly.
Lee

steve herlong

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Re: Holding Tank Vents on 44.5
« Reply #3 on: June 26, 2017, 02:51:21 PM »
Burt, I think you just solved a mystery that has been annoying us aboard Rise for years now!  The venting setup on my H49 looks quite nice by collecting together and teeing the venting locations for the holding tank and fuel tanks into the starboard transom vent fitting along with the large engine blower duct vent. 

We have noticed holding tank smells 50% of the time just after we pump the heads.  Lee, you questioned the location of the vents in your first post and likely it is for the same reasons! I have checked every fitting in the entire head and holding tank setups with no solution.  But Burt has most likely solved the problem!

I run AC at the dock much of the time on board in Fla. and in that setup, the warmest air is escaping thru the companionway and also thru the dorade vents up high. This is creating a natural chimney effect as the escaping hot air needs to be replaced and the low point is the engine duct vent where air is naturally being drawn into the boat.  So air from the holding tank vents is being drawn backwards down the engine duct vent into the boat!  That's the likely source!

My solution on the H49 might easily be to tee the vent lines into the starboard aft deck locker drain line.  Does anyone see a potential problem with that?  If for any reason it does not work as expected I can easily put thru hull vent fittings in that same general location.

Thanks again Burt!

Steve Herlong

Rise

burtpreston

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Re: Holding Tank Vents on 44.5
« Reply #2 on: June 26, 2017, 02:12:03 AM »
The holding tank vents on Exuberant, hull no. 83, connect to the engine room blower duct close to the transom, in the port lazerette.  The fuel tank vents also connect to the same duct right beside the holding tank vents.

We found that with the dodger in place, with wind blowing over the bow, that low pressure is created in the companionway hatch, which pulls in air through the aft ports and hatch. It also pulls in air from the transom through the engine room blower duct. If you are flushing either head, this pressurizes the holding tank, forcing holding tank air out the vents, into the blower duct, where the low pressure in the cabin pulls the holding tank air into the engine room. This discourages flushing the heads, which creates other problems.

We solved this problem by putting two vent fittings in the port hull about a foot from the transom and about 8 inches below the deck. Then the holding tank vents were re-routed to these new vent fittings and the old ones were capped.

Burt Preston
Exuberant

libelo.lee@gmail.com

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Holding Tank Vents on 44.5
« Reply #1 on: June 20, 2017, 05:54:38 PM »
First off.. do they exist? If they do, where are do they come through the hull?

If they don't has anyone had experience installing them?
thanks!
Lee L - Alchemy H44.5

 

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