Had a wierd experience last night at Reed Bingham State Park in southern Georgia. Hooked up to shore power and water, everything fine, until I flushed the john. Thetford high, about 3 years old. Water flew out of the intake all over the place! I had the pressure control fixture properly in place at the intake, and didn't think the park water was that high, but then realized I was hearing the coach pump when I opened the valve. Shut the pump off and all was well. I don't know if this is the first time I forgot to turn off the pump or if something may have failed to work as intended. No harm, no damage, just an enlightening little lesson.

Sometimes air in the lines will do this too.

At least most RV potties flush from the top.



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I have done the same thing, when connected to the local water source, turned on the pump for a bit more pressure during a shower. Still take short showers but feels better with higher pressure.