Use 1 inch or 1 1/2 inch head hose

[Rogerh]

Hi everyone,
In my continueing saga of changing out all the hoses I have found that the Jabsco silent flush heads that I have, 3 of them, all have 1 inch output hoses because they have the macerator built into the head. The run from the aft head to the holding tank is about 35 feet. The two forward heads are about 15 feet each. The holding tank has 1.5 inch openings. I am debating running it all in 1 inch till I get to the holding tank and then convert to 1.5. I will use PVC for the long runs with hose on each end and hose where needed to avoid flexing issues. The 1 inch would be easier to run but I wanted to get some feedback on this to make sure I don't do something that I will regret. The old hoses are all 1.5 inch. Thanks for your inputs.

 

[psneeld]

I have a 10 foot run of 1 inch from my macerator...barbed into 1" PVC for the long straight run...no problems after 2 years.

 

[Rogerh]

That is about what I am looking at. Thanks

 

[Phil Fill]

We have a 1” connect to the toilet with a adaptor to 1 ½” . The long run is 1 ½” hose. the reason is that if the stuff will go through a 1” it will go through a 1 ½”. 17 years we have not had a plug in the 1 ½” hose. They all have been in or at the toilet 1” discharge.

 

[FlyWright]

I have the Jabsco Quiet Flush. Like Phil, we have the 1 " to 1 1/2" adapter about a foot from the head in an accessible area, then run the 1 1/2 inch flexible hose continuous about 12 ft to the holding tank. Never had a line clog or a problem, but if it happens, I'll know where to look and can easily get to it.

 

[psneeld]

use 1" with macerators and never had a clog...wonder if anyone has necked down to 1/2" and ever had a clog?

my guess if it gets out of the macerator 1" discharge with plenty of water...it's not going to clog in the tubing/pipe either.

2 years with 2 toilets being used EVERY DAY as a liveaboard and no clogs on the 1" lines....even with a liveaboard girlfriend who uses the head quite a bit.

 

[Keith]

Bigger is better. Stick with 1.5".

 

[sunchaser]

From a technical standpoint, pumping solids is facilitated by velocity to prevent things form settling out and clogging the line. A 1.5" line has more than twice the area of a 1" line thus stuff will move slower. Often the line will settle out to the point where critical velocity is indeed achieved, but the line now is coated with stuff that could eventually clog.

A good way to cheat this crappy conundrum is to read the install manual for recommended line size. The toilet manufacturer has already calculated the critical velocity for staying out of trouble.

 

[psneeld]

From a technical standpoint, pumping solids is facilitated by velocity to prevent things form settling out and clogging the line. A 1.5" line has more than twice the area of a 1" line thus stuff will move slower. Often the line will settle out to the point where critical velocity is indeed achieved, but the line now is coated with stuff that could eventually clog.

A good way to cheat this crappy conundrum is to read the install manual for recommended line size. The toilet manufacturer has already calculated the critical velocity for staying out of trouble.

I agree...my macerator outlets are 1 inch and the velocity factor works great as I have clear vinyl tubing for a couple short runs and it stays clean.

 

[HopCar]

I'm with Sunchaser and PSneeld on this one. You want to clear the hose each time you flush or stuff will settle and harden.

Jabsco provides those adapters for people who are replacing manual toilets and already have 1-1/2" hose in place. I'd use the 1" hose and be sure to flush long enough to clear the hose.

 

[FlyWright]

I agree...my macerator outlets are 1 inch and the velocity factor works great as I have clear vinyl tubing for a couple short runs and it stays clean.

Clear vinyl sanitation hose? I've seen black and white sanitation hose but never clear. Other than use of PVC pipe, I'd steer clear of non-sanitation hose due to odor permeation.

 

[CPseudonym]

Increasing size in drainage lines is done for one primary reason, to increase carrying capacity. Additional fixtures attached in main runs is an example. Increasing diameter for the sake of avoiding clogs sounds intuitive but is bad practice especially in pump discharge lines. As Sunchaser pointed out if you lose velocity you lose the self scouring characteristics the engineer intended. Transitions from hose to pipe is a good idea but fit them with care as transitions and change of direction are the two most likely future blockage locations so should be minimized.

Interesting side fact is municipal waste systems are being rethought with smaller diameter main sewer drain sizing. The downside of water saving fixtures is that less water going through municipal sewers allows solids to fall out of suspension and increased mainline stoppages dramatically.

 

[Rekindle]

15 foot run with 1 inch PVC hose from macerator/head to the holding tank.

After 5 years I've had no problems. I specifically chose this set up because I'm on a 28' boat with a small holding tank and small FW tank. The smaller diameter hose allows me to clear the line easily without over filling the holding tank or draining the FW tank. I always have fresh water sitting in the line instead of sewage.

 

[psneeld]

Clear vinyl sanitation hose? I've seen black and white sanitation hose but never clear. Other than use of PVC pipe, I'd steer clear of non-sanitation hose due to odor permeation.

no problem after 2.5 years because it's usually flush water that sits in them..they are short runs and can be replaced easily and cheaply if necessary.

My head sytem is a simplified version of the costly, hard to maintain, odor abundant systems that boat manuafacturers use...I'm very happy that I thought though my design and implementation and didn't succumb to traditional failure prone thinking...

plus living aboard helps keep stuff moving through the systems ...I think sstems that sit suffer...in particular salt water flush systems.

 

[jandcinok]

I had a similar issue. Our system had approx. 2 ft of 1 in hose then was adapted to 1.5 in. It just didnt make any sense why we couldnt plumb all the way to the tank with 1 in. hose. I contacted Jabsco (Xylem now, I think) and they said 1 in. should be just fine, I won't be able to tell the difference.

 

[FF]

IF modifying the system be sure to use a vent hose that is at least 1 inch , 1 1/2 being better.

The reason is in some areas the toilet suck boat will have a very large capacity poop pump , and you do not wish to collapse your holding tank.

Whenever being pumped , be sure to log the event and get a receipt , to wave at the poop police inspectors..

 

[Phil Fill]

Our Jabsco head has a 1” outlet, but I run a 1 ½” from the head to the holding tank. I figure if stuff can get pass though a 1” it will pass through a 1 ½”, to prevent plugging. 18” years all the plugs have been in the head or the 1” outlet, never had a plug in the 1 ½” hose 20+ ft hose run.

 

[jandcinok]

Oh, by the way. If you have questions about Jabsco products, there's a place in their website for that. I did, and had an answer back in about 10 min. Pretty cool!http://www.jabscoshop.com/marine/marine-toilets/

 

[jandcinok]

For Rogerh. I noticed your intent on using some PVC which we did also, got rid of about 15 ft. of hose total. Pay some attention to your hose barb connections ( hose barb X PVC ), they're NOT all the same, and getting the proper connections for your hose will save you a LOT of cussing..............<G>

 

[psneeld]

Our Jabsco head has a 1” outlet, but I run a 1 ½” from the head to the holding tank. I figure if stuff can get pass though a 1” it will pass through a 1 ½”, to prevent plugging. 18” years all the plugs have been in the head or the 1” outlet, never had a plug in the 1 ½” hose 20+ ft hose run.

I've never had a plug in a 15 foot 1" hose.....never had my anchor drag either...yet.

Narrow, swift rivers tend not to plug up with sediment...the wide, slower moving ones do tend to.

That might be what the engineers of the pump thought with a 1" hose outlet...that's what I think too....

 

[jleonard]

Narrow, swift rivers tend not to plug up with sediment...the wide, slower moving ones do tend to.

That might be what the engineers of the pump thought with a 1" hose outlet...that's what I think too....

They probably thought more about the savings in the mold and the amount of plastic with the smaller outlet.:lol: