4-way pump switch for outdoor shower

[Snackchaser]

When doing a modification to install an outdoor valve control switch (Electric valve control… with a twist,) I realized that an outdoor pump switch would also be nice when doing valve operations.  Not only that, but the pump switch is handy for the outside shower too!

To understand this modification, it helps to know about 3-way and 4-way switches.  The two existing pump switches are common “3-way” switches like you would find in a hallway to turn the light on from either end.  To add a third switch to the circuit, then you need a “4-way” switch, but they are less common and not readily available in RV style switches.  Fortunately though, the more common Double Pole Double Throw (DPDT) - On/On switch can be modified to make a 4-way switch just by adding two jumpers.

This modification requires removal of the cubby/shelve under the bathroom vanity, and it’s a good opportunity to do the “Bathroom Vanity Cubby Modification“ by Frank C, it makes access to this area a whole lot easier.  With the cubby removed, locate and cut the two grey wires going to the bathroom pump switch, these are the “travelers” that go to the main pump switch.  Splice four new wires to the cut grey wires and route them under the dinette to the new switch.  I used a rubber booted DPDT switch and mounted it in the outdoor storage area on the front facing wall.  It snap-fits into a 3/4” hole.  The new wires were protected by split sheathing.

I also added an optional LED indication light for the new 4-Way switch, which is powered from the pump’s +12v whenever the pump is energized.  Amazon LEDs are ridiculously inexpensive and easily mounted in a 3/16” hole.

I hope someone finds this useful.  Cheers! Geoff

Shopping list:

• DPDT On/On switch No KDH3BNA1BBB (From Digi-Key company)
• 3/8” split wire sheath
• Optional 12 Volt 5mm LED Light with LED bezel Holder