Shower sump pump

[Sadiemae]

I need to replace the shower sump pump (old Rule 400gph) and hoses to the overboard thru-hull. There is an existing anti-siphon loop. Should I use the head sink thru-hull and how best to tie into this? The old plumbing was disconnected or missing so not sure what the po had set up. Thanks.

[capn_billl]

I'm not sure about your question, but draining both the sink & the shower into the shower sump, and tying the sump output through the anti-siphon loop to the existing thru hull should work.

I have an extreme adversion to thru hulls and use as little of them as possible. My previous boat had seperate head sink that drained directly to a thru hull, and shower sump that had it's own thru hull.

I wouldn't tee the output of the shower sump to the head sink drain, unless you didn't mind your shower water backing up into the sink.

[Sadiemae]

Hi Capn bill,
The original plans (27 years old) show the head sink draining to its own thru hull and the shower draining to its own thruhull but the shower thru hull does not exist on the boat. The hose from the head sink is attached to one end of a double ended bronze barbed piece with two male ends. Nothing is on the other end. This hose is lying next to the two thru hulls for the sink and head intake. The output hose of the shower sump has been cut off and is just hanging near the sink hose. I'm not sure what the previous configuration was.

I would mind shower water backing up into the sink. I have also read where some have tied the shower output to the head intake. That does not sound good to me either.

Thanks for your comments.

[donradcliffe]

My shower drain has a whale 400 and is teed into the sink drain. I hear the sink drain gurgle when the pump works, but it doesn't come close to backing up into the sink. I don't think that little pump will generate much head--kind of like your washer outlet at home which discharges into a short standpipe, but only overflows when the sewer backs up.

[capn_billl]

If you tee the shower sump output AFTER the antisiphon loop the risk of a backup is small. But the head sink volume is so low why not just add to the sump?