Raritan PHCII head mystery- many strokes to empty bowl

[High Wire]

So here is the details:
New head, new discharge 1 1/2" hose
Holding tank empty, vent clear
Head is a Raritan PHCII manual head

Hose run: From the head, down about 18" under a bulkhead, then up 3 feet to a vented loop, then down about 2 feet and a 15 foot flat horizontal run then down a foot to the holding tank. The PHCII head is supposed to be able to pump up to 10 feet.

What happens - Knob to FLUSH. Bowl fills faster than pumps out. You can feel significant effort on handle moving seawater side water into bowl. Bowl level will go up as long as you keep pumping.

What happens - Knob turned to DRY bowl. Bowl stops filling. Pumping effort is MINIMAL (can't feel any water moving). Croaking sound from bowl rim. With normal effort the water just sits there with no motion. The only way to make the bowl level lower is use extreme lifting up rapidly as possible on the handle. The bowl will eventually empty after about 20 strokes this way.

What I've done: Completely disassembled and cleaned the flapper valve, the piston, the ball check valve, and the joker valve. Flushed the discharge line with a garden hose to the HT. Other than a little soft piss-crete, no blockages. Everything looks normal.
Calls to Raritan were no help. I can read the troubleshooting section just as good as they can.

What is confusing is that if there was a discharge blockage, the piston would cause high effort, not low. You would have a hydraulic lock. Same if the flapper valve was stuck closed. It acts like no piston at all. Yes the piston rod is connected.

 

[Capt. Jon]

What about the little vent valve. From memory it has a small ball and spring. Maybe it's stuck open not allowing the pump to push.

 

[HeadMistress]

Your toilet discharge line goes down about 18" then up 3 feet then down another 2 feet and a 15 foot flat horizontal run... then down a foot to the holding tank....it's a 20' long roller coaster!

And where did you get the idea that the PHC--which, btw, uses the same pump as the PHII--is supposed to be able to lift bowl contents 10'?? Up to 4' in the dry mode, a bit further in the wet mode immediately after the toilet. The furthest ANY manual toilet will move bowl contents in a completely horizontal run is about 6'... You're asking it go further than that through all those ups and downs and then go 15 MORE feet! No wonder you're having problems!

And btw...how long is the toilet intake line? That "croaking" sound from the rim indicates another set of problems.

The solution: replumb the system to create a run that makes sense. I'll be glad to help you figure out how to do that if you'd like to send me a PM.

The PHII/PHC is the best manual toilet in its class (under $1000)...you'll love it once we've solved all your plumbing problems.

Jon....I think you may be confusing the PHC--which is a manual toilet--with Crown Head, which isn't.

 

[Xsbank]

I bet its nothing to do with plumbing and more to do with diet...8^)

 

[Capt. Jon]

Nope, not confused, the small check valve is sticking out of the wet/dry valve housing facing the front of the toilet. I had this little valve stick open on anther boat and it would not pump.

 

[HeadMistress]

Ok...you're referring to the air valve. There's a tiny little diaphragm in it that creates an air "bockage" when it wears out. He wouldn't be able to pump the toilet at all in the dry mode (or the wet, I forget which but it's only in one of 'em)...starts owners looking for a clog. Not likely to be the problem in a brand new toilet though. I'm pretty sure that once we get rid of the 20' "roller coaster" plumbing, it'll work just fine.

 

[Capt. Jon]

Ok...you're referring to the air valve. There's a tiny little diaphragm in it that creates an air "bockage" when it wears out. He wouldn't be able to pump the toilet at all in the dry mode (or the wet, I forget which but it's only in one of 'em)...starts owners looking for a clog. Not likely to be the problem in a brand new toilet though. I'm pretty sure that once we get rid of the 20' "roller coaster" plumbing, it'll work just fine.

Yep, I bet your right! That's a long ways to pump by hand!

 

[High Wire]

The pumping mystery is solved. The outlet joker valve was staying partially open at rest. I did not think it would make that much difference but it did. Replaced the valve and the head now pumps and empties the bowl normally all the way to the tank (visually verified through the top inspection port, yuk!) Thanks to Peggie for her help.

 

[RT Firefly]

Greetings,
Mr. HW. Joker valve. Aptly named.

Further...I wondered why it was called a joker valve and ran across this article. Didn't answer my question but, interesting, all the same...

http://www.practical-sailor.com/issues/37_31/features/Joker-Valves-for-Marine-Heads_11065-1.html

 

[psneeld]

Like many hand pumps...while maybe not recommended, when things are working correctly, pumping 10 or 15 feet except straight up isn't unreasonable. This was only about 18 inches head. Manual bilge pumps usually handle way more head than that.

Good catch Archie.