Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 27-05-2014, 10:15   #1
Registered User
 
Seawindii's Avatar

Join Date: Sep 2012
Location: NYC
Boat: Allied Seawind 32
Posts: 39
Adding Discharge Pump

I am in the process of replacing all my sanitation hoses and Y valve and want to add a discharge pump while I am at it. While reading the installation manual for the Sealand Sanipump it says I need to add a second vented loop on the output of the pump. Not sure if this is true as I am also adding a Y valve between the pump and the holding tank.

Just wondering if some of you might be able to give this a sanity check. Is there a better way?
Attached Thumbnails
Click image for larger version

Name:	photo (36).jpg
Views:	132
Size:	402.7 KB
ID:	81972  
__________________

__________________
Seawindii is offline   Reply With Quote
Old 27-05-2014, 10:22   #2
Senior Cruiser
 
Cheechako's Avatar

Cruisers Forum Supporter

Join Date: Aug 2006
Location: Skagit City, WA
Posts: 19,363
Re: Adding Discharge Pump

Hmmm... so it says to add a loop between the output of the macerator/discharge pump and the seacock? I wouldn't. I'd make that as straight and free flowing as possible. Assuming you usually have the seacock closed unless pumping.
__________________

__________________
"I spent most of my money on Booze, Broads and Boats. The rest I wasted" - Elmore Leonard











Cheechako is online now   Reply With Quote
Old 27-05-2014, 11:54   #3
Registered User
 
Seawindii's Avatar

Join Date: Sep 2012
Location: NYC
Boat: Allied Seawind 32
Posts: 39
Re: Adding Discharge Pump

That was my thought. But you can certainly see if the seacock was open and the Y between the holding tank and pump wasn't set correctly it could cause backflow into the holding tank. I'd prefer it to be more idiot proof but maybe this is how it's done.
__________________
Seawindii is offline   Reply With Quote
Old 27-05-2014, 13:28   #4
֍֎֍֎֍֎֍֎֍֎

Cruisers Forum Supporter

Join Date: Apr 2006
Posts: 13,037
Re: Adding Discharge Pump

In the interests of KISS, you could (should?) eliminate the two Y valves closest to the head, and the hose between them. That would mean the head always pumps into the tank, yes, and then any "direct" discharge still has to be FROM the tank, but isn't that a small price to pay for eliminating the extra fittings and hose?

Putting in the second vented loop will act as a siphon break, cheap insurance against the chance of the discharge line siphoning back and filling the tank and the entire system. Ugh, what a mess that could be.

Just one man's opinion.
__________________
hellosailor is offline   Reply With Quote
Old 27-05-2014, 13:56   #5
Registered User
 
Seawindii's Avatar

Join Date: Sep 2012
Location: NYC
Boat: Allied Seawind 32
Posts: 39
Re: Adding Discharge Pump

I knew there had to be a better way. Your suggestion makes sense. I was making it too complicated. The second vent loop and pump placement will be a challenge. Back to the drawing board. Thanks!
__________________
Seawindii is offline   Reply With Quote
Old 27-05-2014, 14:15   #6
Registered User
 
Stu Jackson's Avatar

Join Date: Jan 2011
Location: Cowichan Bay, BC (Maple Bay Marina)
Posts: 6,386
Re: Adding Discharge Pump

Do you only have one outlet from the holding tank?
__________________
Stu Jackson
Catalina 34 #224 (1986) C34IA Secretary
Cowichan Bay, BC, (Maple Bay Marina) SR/FK, M25, Rocna 10 (22#) (NZ model)
Stu Jackson is online now   Reply With Quote
Old 27-05-2014, 14:19   #7
Registered User

Join Date: Sep 2012
Posts: 26
Re: Adding Discharge Pump

"sanity check". Pun intended?
__________________
ranchhand is offline   Reply With Quote
Old 27-05-2014, 17:14   #8
Registered User
 
Seawindii's Avatar

Join Date: Sep 2012
Location: NYC
Boat: Allied Seawind 32
Posts: 39
Re: Adding Discharge Pump

Stu... I have basically as in the diagram. One inlet, one outlet. Stainless custom tank almost inaccessible without major deconstruction.
__________________
Seawindii is offline   Reply With Quote
Old 28-05-2014, 07:20   #9
Registered User
 
Seawindii's Avatar

Join Date: Sep 2012
Location: NYC
Boat: Allied Seawind 32
Posts: 39
Re: Adding Discharge Pump

So here is the latest config. I eliminated the direct discharge piece, which simplifies things considerably. Direct discharge will be accomplished through the tank/pump.

Question: As I have eliminated the Y valve to thru hull on the output of the head do I really need the vent loop between the head and the holding tank?
Attached Thumbnails
Click image for larger version

Name:	photo (37).jpg
Views:	211
Size:	401.8 KB
ID:	82015  
__________________
Seawindii is offline   Reply With Quote
Old 28-05-2014, 07:51   #10
֍֎֍֎֍֎֍֎֍֎

Cruisers Forum Supporter

Join Date: Apr 2006
Posts: 13,037
Re: Adding Discharge Pump

Suppose you moved the discharge Y valve, and the deck pumpout, to the left side of the vented loop. Which should already be right up under the deck. Less plumbing.

And of course move the discharge pump to the other side of that loop, down by the thru-hull.

From what I can tell the vented loop in between the head and the holding tank isn't necessary, but it ensures that if you have a leaky or defective joker valve, the holding tank can't empty back into the head. Practical insurance. If the run from the head to the holding tank is all downhill, not so much a concern.
__________________
hellosailor is offline   Reply With Quote
Old 28-05-2014, 08:23   #11
Registered User
 
Capt.Don's Avatar

Join Date: Aug 2010
Location: Altadena, CA
Boat: Tartan 3500
Posts: 611
Images: 1
Re: Adding Discharge Pump

This is how I plumbed my SeaLand pump. Note, as per my similar post, my pump's duckbill valves somehow got inverted.
Attached Thumbnails
Click image for larger version

Name:	IMG_0617.jpg
Views:	87
Size:	353.1 KB
ID:	82018  
__________________
Capt.Don is online now   Reply With Quote
Old 28-05-2014, 10:05   #12
Registered User
 
Seawindii's Avatar

Join Date: Sep 2012
Location: NYC
Boat: Allied Seawind 32
Posts: 39
Re: Adding Discharge Pump

Don, looks like a similar set up. I am no expert but the output of your pump may need to go through a vented loop. If the discharge seacock is inadvertently left open, backflow could occur, which might overcome the ability of the pump valves to stop it.

Hellosailer, my drawing reflects actual routing of hoses currently. Unfortunately I don't have much room to play around with.
__________________
Seawindii is offline   Reply With Quote
Old 28-05-2014, 10:14   #13
Registered User
 
Capt.Don's Avatar

Join Date: Aug 2010
Location: Altadena, CA
Boat: Tartan 3500
Posts: 611
Images: 1
Re: Adding Discharge Pump

Seawindii, not quite - I have separate thruhull discharge thruhulls for head and macerator and a y-valve to route head discharge to the holding tank or overboard. The way you have this setup, you can only flush the head to the holding tank. Your y-valve only controls whether the macerator pump or shore pump-out is used to empty the holding tank. Is that what you want? I find it convenient to dump directly overboard (outside 3 mile limit) and bypass the holding tank completely.
__________________
Capt.Don is online now   Reply With Quote
Old 28-05-2014, 12:07   #14
֍֎֍֎֍֎֍֎֍֎

Cruisers Forum Supporter

Join Date: Apr 2006
Posts: 13,037
Re: Adding Discharge Pump

Seawind, I'd say it was that "American Puritan heritage" thing, but sailboats world over seem to be afflicted with the same lack of attention to proper head plumbing. Or installation. Or just leaving space to correct either.

Or, maybe that's intentional, to ensure the gentler side stay ashore?
__________________
hellosailor is offline   Reply With Quote
Old 28-05-2014, 13:43   #15
Registered User
 
Terra Nova's Avatar

Join Date: Apr 2007
Location: Marina del Rey, California
Boat: Freya 39 cutter- Terra Nova
Posts: 3,649
Re: Adding Discharge Pump

Quote:
Originally Posted by Seawindii View Post
So here is the latest config...


Eliminate both vented loops. Plumb head discharge as directly as possible into the top of the holding tank, with no sharp turns. Replace the Y-valve with a sanitary-T. And plumb the waste discharge pump directly from that T, overboard. Keep the seacock closed unless pumping overboard.

Keep it simple. Take care to run hoses so they are as short as possible, that they pitch down to their destination (go high at the head, to pitch down to tank), and that there are no traps.
__________________

__________________
1st rule of yachting: When a collision is unavoidable, aim for something cheap.
"whatever spare parts you bring, you'll never need"--goboatingnow
"Id rather drown than have computers take over my life."--d design
Terra Nova is online now   Reply With Quote
Reply

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Bilge Pump Discharge at Waterline sandycohen Plumbing Systems and Fixtures 15 26-07-2011 09:23
Help with Adding a Water Pump in Galley Trader Susan Plumbing Systems and Fixtures 4 20-07-2010 21:23
AC discharge thru-hull: below waterline, or piss off my neighbours? Geoff S. Plumbing Systems and Fixtures 16 24-04-2008 08:24
No Discharge Zones engcon Liveaboard's Forum 3 10-01-2007 01:51
Head discharge lines clogged with marine growth? ssullivan Plumbing Systems and Fixtures 27 23-10-2006 10:04



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 12:20.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.