[C38] Head direct discharge and holding tank seacocks. Closed or open when sailing?

[charles]

If the vent hose is not plugged you should not get pressure in your holding tank.  I would suggest taking the vent hose off your holding tank and pump some water to see what happens.  My guess is the vent hose line is plugged. 
-------- Original message --------From: Vassili Valayannopoulos <vassilival.boston at gmail.com> Date: 7/30/25  11:07 AM  (GMT-06:00) To: Catalina 38 Listserve <listserve at catalina38.org> Subject: Re: [C38] Head direct discharge and holding tank seacocks. Closed or open when sailing? 

Hi Douglas,
 
I checked the vent hose and stanchion with a wire and it goes all the way into the holding tank. Also U don’t quite understand how opening the direct discharge seacock
 helps take pressure off the holding tank circuit when the Y valve is switched to holding tank.
 
Thanks!
Vassili
 
 
 




From:
Listserve <listserve-bounces at catalina38.org> on behalf of Douglas Allardyce <doug.allardyce at att.net>
Date: Wednesday, July 30, 2025 at 12:00 PM
To: listserve at catalina38.org <listserve at catalina38.org>
Subject: Re: [C38] Head direct discharge and holding tank seacocks. Closed or open when sailing?


Check the vent on the tank





From: Listserve <listserve-bounces at catalina38.org> on behalf of Vassili
 Valayannopoulos <vassilival.boston at gmail.com>
Sent: Sunday, July 27, 2025 4:28 PM
To: listserve at catalina38.org <listserve at catalina38.org>
Subject: [C38] Head direct discharge and holding tank seacocks. Closed or open when sailing?


 



Hi Folks  

 


The head on my C38 is connected to a holding tank with a macerator pump and its own discharge seacock and I also have a direct discharge hose with its own seacock. I have a Y valve that allows to select one
 or the other.


 


When I want to evacuate the bowl into the holding tank I need to have the direct discharge seacock open otherwise I am getting overpressure in the holding tank that prevents me from pumping (even when the
 holding tank is empty and even when the holding tank’s seacock is open). 


 


I would assume that with the Y valve switched to holding tank and the direct discharge seacock open the risk of seawater back flow is low when underway but would love to hear your thoughts and how you handle
 this on your boats. It would be annoying to have to open and then close the direct discharge seacock every time someone needs to use the head.


 


Thanks in advance!


Vassili 


 


Sailing on Naftaki 


Winthrop MA








-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://catalina38.org/pipermail/listserve_catalina38.org/attachments/20250730/a4402135/attachment.htm>