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Grey/Black Tank Capacities

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Grey/Black Tank Capacities
« on: January 17, 2021, 08:27:58 pm »
  When we first fell in love with a PC 3100 in 2017 from an article in FMCA magazine the tank capacities were: Grey 50 gals, Black 23 gals. My research says In 2018 that changed to Grey 35 gals, black 23 gals. After we bought our (used to us) 2019 PC/3100 and the DW noticed a shower issue (very quick full tank) I discovered from company stats it changed to Grey 23 gals, Black 45 gals.

  Before I ask the factory how I change that equation to something more useful... Does anyone have a clue why the capacities changed so much. We (like most folks?) generate more grey than black stuff.

  Just wondering. Has any tried to "flip" the tanks?


Hank & Joyce Whitney
Custer, SD
2019 PC Model 3100



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Re: Grey/Black Tank Capacities
« Reply #1 on: January 17, 2021, 10:28:12 pm »
Itís a simple 10 minute job to install  a water saving  Oxygenics Body Spa shower head. It only uses 1.8 gpm but also boosts the water pressure, so itís a win-win.
« Last Edit: January 18, 2021, 12:41:10 am by CalCruiser »
Goin' where the wind goes...


Ron Dittmer

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Re: Grey/Black Tank Capacities
« Reply #2 on: January 17, 2021, 11:32:29 pm »
Hi custerhank,

Your situation is identical to ours.  We have a 23 gallon gray tank and a 35 gallon black tank.  The tanks are in fixed locations, tank assignment is determined by the location of the toilet within each floor plan.

When we picked up our PC-2350 from the factory back in 2007, Phoenix explained to blend the tanks because the gray tank will fill before you run out of fresh water.  You open the gray valve first, wait 5 seconds, then open the black tank valve, wait until the water slushing sound quiets down, then close both valves.  The process floods the near empty black tank with gray tank water.  This is a very good thing because the gray soapy water helps clean out the pee & poo.  Unfortunately it is a hassle to go out to do that at the worst opportune time....when taking a shower.  We got good at anticipating it so we are proactive.

One day I hope to wire in redundant tank control switches mounted inside the bathroom vanity (out of sight) so I can flood the black tank from inside the bathroom.  Our bathroom vanity is directly above the sanicon system so wiring them should be very simple.  I have the switches but lack the motivation.
« Last Edit: January 17, 2021, 11:42:13 pm by Ron Dittmer »
Ron (& Irene) Dittmer



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Re: Grey/Black Tank Capacities
« Reply #3 on: January 17, 2021, 11:59:48 pm »
Custerhawk you're singing to the wrong choir, not only are the Phoenix Cruiser tank capacities small but they're also incorrect. I complained about this same thing on this forum but was told Phoenix Cruiser doesn't have to give the correct tank capacities.