bilge pump wiring

[barrowgv]

i am surprised nobody knows how to wire a dual(high-low) bilge pump installation with float switches. have searched all sites including manufacturers. boat manual is useless for dual. any ideas.

 

[Silvertip]

Re: bilge pump wiring

There is nothing special about this but some folks do some "creative" wiring so we can only tell you how it "probably" should be -- not what you actually have. Float switches typically have three wires. Manual (switched +12v), hot all the time, and ground. You didn't provide wire colors so you need to identify those. Black is typically ground.

1) Float switches have one wire that connects directly to battery. This is the hot all the time feed which allows the pump to run if water rises far enough to activate the switch when the boat is not attended and the console switch is turned off.

2) Each pump has a ground wire. That wire needs to connect to battery NEG or a ground buss if you have one.

3) The console switch normally when set to ON or MANUAL bypasses the float switch and therefore powers the pumps. You may have two switches since you have two pumps. This is important because if water is high enough to reach the lower pump but not high enough to reach the upper pump, if both were powered by the same switch the upper pump would run dry. Maybe a problem, maybe not. Therefore, power from the fuse panel goes INTO the switch. The OUT side of the switch feeds the pump. If both are wired to the same switch then the third wire from the pump would be the one to connect to the switch.

 

[seabob4]

Re: bilge pump wiring

i am surprised nobody knows how to wire a dual(high-low) bilge pump installation with float switches. have searched all sites including manufacturers. boat manual is useless for dual. any ideas.

Are you taking about a 2 pump, 2 switch setup where the first pump and switch are the primary, and the second pump and switch are the "high water"? We do it all the time at Proline. The primary has one lead off the switch going to constant hot, the second lead off the switch combined with the hot lead off the pump run fwd to a switch on the dash. Comes on auto or manually. The high water has one lead off the switch to constant hot, the second lead wired to the hot off the pump, plus a lead going forward to an alarm at the helm...

 

[barrowgv]

Re: bilge pump wiring

this is searay aj 2001. the one instrument panel switch is an On-Auto. the wiring at the bilge harness includes one brown-yellow(hot), two brown-black, single brown, single black. the pumps both have two gray. one pump is high water with float. other is low with float. i am assuming the continuous hot b/y goes to the low pump.