Author Topic: H46 holding tank vents  (Read 528 times)

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Re: H46 holding tank vents
« Reply #5 on: July 31, 2022, 12:19:27 PM »
Hi Brian,
We've had our H46 #70 Adina for about 12 months. We've not noticed any smells from our holding tanks, however our boat survey had mentioned about changing the 3/4 inch breather pipes for shorter 1.5 inch pipes. We've had such a steep learning curve, that this wasn't on our priority 'to-do' list. Nevertheless, having seen the replies to your post we had a quick look on Adina, and found the filters for both holding tanks attached to the top of the port lazarette. They are 'Sanigard holding tank Breather filters'.
It looks like they are no longer available in the UK (where we are based) and the suggested replacement part suggested is:
Wishing you good luck with finding yours.
Carole & Andrew

SV True North

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  • Hylas 54/42
Re: H46 holding tank vents
« Reply #4 on: July 30, 2022, 01:59:16 PM »

On my 54, the filters are in the port and starboard aft lockers on the vent hoses just below the deck.  Follow the vent hose near your stern vent outlets forward and you should find them nearby.

I to am interested on what replacement filters Merrill used as I would like to replace the ones on True North with refillable ones.

SV True North
Hylas 54 #42


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Re: H46 holding tank vents
« Reply #3 on: July 29, 2022, 11:43:52 AM »
Hello Merrill,

Could you share more information on where you located those original filters on your 46 and where you were able to purchase the replacements?

H46 #43


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Re: H46 holding tank vents
« Reply #2 on: July 29, 2022, 10:56:20 AM »
On board Ambition, there were inline carbon filters in the head vent line. I found that filter was to say the least... old and grungy .. I suspect that the tank(s) was overfilled at one point and head contents made their way into the filter. I have changed the filters and the resistance that you describe was dramatically reduced. It was quite the search to locate the filters but perhaps you may want to give it a try. The filters I installed, are maintainable and every few years, I change the carbon in them.

S/V Ambition H46 #40


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H46 holding tank vents
« Reply #1 on: July 28, 2022, 07:07:03 PM »
Has anyone relocated the holding tank vents on their H46 putting them nearer to the tanks and making the hose larger diameter.
I have been thinking about doing this for a while but just can't choose a location which would be above water when heeled. The existing vents located on the transom with the long small diameter hoses make using the tanks difficult to pump into and there is a fear of collapsing them while pumping out.

Andy H46#32 True Brew.


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