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2007 280 Sundancer. Can’t figure...

Guest Contributor

2007 280 Sundancer. Can’t figure out the sump pump as it never seems to start. When is it supposed to switch on? Is it just a closed grey water from the head to the septic, or is it also able drain water from below the stairs?  Tried referring to the schematics but they weren’t helpful. Thanks in advance!


Guest Contributor
Mine works on a float switch.

Guest Contributor
On my 310 similar age, there is a junction box under floor through a hatch. Had to open mine and clean out muck to get it to operate. Same as toner, works on a float and pump. Try cleaning it else may need a new pump.

Guest Contributor
I replaced the shower sump on my 340 about six months ago. Replacement was easy to find online. Head (shower) floor drains into the sump and raises the float switch, which activates the pump. Sump is connected to a discharge hose, which pumps the gray water overboard. Not a bad project, relatively speaking. Good luck!

Rising Contributor
Welcome to the forum.

All prior replies correct.

A periodic maintenance step I perform is disassembly for cleaning to ensure proper operation.

About a decade ago I swapped the in line output check valve because of deterioration.

Guest Contributor
If it's full but not pumping it's the float switch. It's located under the step so see if it's full ? You can also take the cover off and lift the float to see if the pump comes on?

Guest Contributor
The AC condensate and shower both drain into the sump box. a bilge type pump pumps the accumulated water out a "through-hull" fitting on the starboard side. Some water (an inch or two) may stay in the sump box. If the sump box is full, the float switch or pump is not working properly or possibly there is a restriction in drain line. The circuit breaker for the sump pump is located on the main DC breaker panel.

Guest Contributor
It was indeed a stuck float switch. Took off the cover, cleaned everything up, toggled it manually a few dozen times, and it’s working great. Thanks for the help!