Winterizing a Raritan PHII or PHEII toilet (Long)

Vic Willman

New member
Mar 5, 2001
RO Number
Yeah, I know, it's only July, why bring this up so early? Surprising as it may seem, I'm getting calls from people in Michigan and Wisconsin who are just now getting their boats into the water, and are having toilet problems that were caused by improper winterizing last fall.

Here's the proper way to do it when the time comes, for PHII and PHEII toilets that are connected to holding tanks. If you have an Electro-Scan, Lectra/San or Purasan connected to the toilet, begin at Step #4:

1. DO NOT pour anti-freeze into the toilet bowl, then pump it a few times and walk away!

2. Turn off the supply water seacock, where the incoming water supply to the toilet connects.

3. After you've turned off the seacock, remove the hose from the through hull fitting, and stick the end of it into your jug of RV anti-freeze. Have someone pump the toilet while you hold the hose in the jug of anti-freeze. When they see the pink fluid circulating around the inside of the toilet bowl, and being pumped out into the holding tank (if you have a holding tank) - then you're done. Leave the hose disconnected from the through-hull until spring. If possible, remove the handle from the seacock, so that it can't be accidentally opened during the time that the boat is out of commission. Now go to the discussion after Step #6.

4. If a treatment system is connected to the toilet, first run the treatment system for 4 or 5 complete treatment cycles. Then turn off the seacock at the discharge through-hull fitting.

5. Remove the plug at the top stack of the treatment system, between the two motors on top of the unit, and pump the treatment box out, so that less than 1" of water remains inside. You can use a hand bilge pump or a pump that chucks up in an electric drill. Pump the contents into a bucket, then empty the bucket into a land-based toilet and flush it away. Replace the plug at the top of the treatment system.

6. Remove the intake hose from the treatment system, coming from the toilet. Place the end of the hose into a bucket. Now go back and follow steps 1., 2., and 3.

Now we'll get into the whys and wherefores. If you simply pour anti-freeze into the toilet bowl and pump the toilet a few times, you've protected the discharge side of the toilet but not the intake side of the toilet. In the front of the toilet's pump, under the selector knob for dry or wet flush is a spring-loaded rubber ball, that is a check valve and controls the incoming rinse water to the toilet. A little water stays in this area all the time. Now, if you don't replace this water with anti-freeze by pumping the anti-freeze through the entire pump, from the intake through-hull area, the remaining water that is in this area will freeze. When the water in there freezes, it doesn't crack the plastic housing or break anything, but instead, it forces the rubber ball down into the water passage immediately beneath it, completely sealing off the passage. Once this happens, you can't pump the pump or bring in any outside water. You force the handle down, and it pops right back up in your face! The inlet valve then has to be disassembled and the rubber ball then must be driven out with a hammer and dowel. It's a real pain in the butt, plus you usually chew up the ball in the process of getting it out of the water passageway, and you have to replace it with a new one!

As far as treatment systems, it isn't a good idea to put anti-freeze in them. All anti-freeze has glycol in it, and if there is any residual chlorine left in the treatment system, glycol and chlorine don't like each other! If you mix the two, in the proper proportions, a lot of heat is generated in a short period of time, and nasty things can happen. Plus, over time the anti-freeze will attack the coating on the electrodes of Lectra/San or Electro-Scan units, shortening their useful life.