Johnson Pump36152 Electro-Magnetic Float Switch,12V,Black,Small

I am starting at 5 stars and will leave it that way unless I experience some problems. At that time, I will adjust the rating if needed.A few things must be realized:1) This switch requires a 12v source to operate the relay inside. So you cannot use it like a simple switch to control anything other than a 12v load with a common negative connection.2) There is a manual operator tab on the side of this unit that allows you to lift the float manually. Lifting it that way does turn on the switch but it does not directly indicate the normal water level that does the same thing. The float operates in a non-linear manner, with the float position not always directly proportional to the water height. The settings are 2-1/4" on and 3/4" off, as stated on the package label. I verified that is the way it works.There are 3 parts inside the switch other than the float. There is a small reed switch that senses the float position. Controlled directly by the reed switch is a 12v relay to switch the load. There is also a small diode on the relay to suppress voltage spikes on the power lead.There are no real electronics inside; so if the circuit fails, I would suspect salt water corrosion of the components terminals to be the cause. The only seal for the chamber with the relay and reed switch is at the wire entry point, and is a simple rubber 3-wire pass-through type. This is the only place that water can enter the chamber unless the case is cracked or broken. The small reed switch would be the next likely part to suspect of failure.For now, it works perfectly in my normal application. I will add follow-up's later.

I recently installed this switch to replace a failed Rule product in a Sea Ray 370 cabin storage bilge. It's small and, with the enclosed design, has very little chance of clogging or being affected by debris that might be in the bilge that could inadvertently keep it in either an ON or OFF state (think of the float on many Rule switches). Wires were quite long allowing for power connections to be made and secured well above the level where water should be able to get into the crimps (I hope!). Documentation was clear making the installation project easy.I recommend this product.CLC

I bought a returned used one from Amazon Warehouse. The issue it had was the white vent ball on top could not open as the cover was glued on too low preventing air from escaping the float chamber, the float could not rise up to activate the switch. This was a manufacturing error and obviously they don't test these switches or they would have caught it at the factory. I cut a slot in top vent cover and pried off the side with the ball vent. Reattaching the cover it them worked fine. Used a solder gun to weld it back on.The design is decent. The electronics are sealed and has no moving wires to break or float seals to leak.EDIT, bought another which also did not work, float refused to rise. This due to top vent cover too tight to the white vent ball. They must have had a production quality problem and proves they don't test these before sale. Easier way to fix is use a heat gun to soften top vent plastic, use a small tool to push the black plastic UP to give white ball room to move. Plastic then hardens into a position that gives white ball room to lift up and let air out of chamber which allows float to rise and turn on the switch.

So far the switch is doing it's job as expected. It replaced the same float switch that had lasted 5 years Easy to install and is working well.

Since it only lasted 1 year before replacing- I will be going through company on its 3 year warranty with the new one.But the replacement was sent in a soft mailer envelope. The pump was out of box-loose in mailer. I am assuming it may have been damaged. Lots of loose noise. Shame on Amazon to ship this way. On phone with Amazon now- boy what a difficult time I am having. Had to ask to be elevated to Supervisor. She actually took care of me in a gracious manner. Still wont get product for several days, ugh!

Bought this to add to bilge pump for automatic bilging. Took the time to install. Tested. Everything working. Only to find it doesn’t turn the pump on when it’s completely submerged. Have to reach into bilge and jiggle the float switch test lever to make it actuate. Now I had to purchase another one. And will have to do the entire job again because of this faulty part. Don’t waste your money. Get the solid state switch.

My old float switch was a two wire and had its own wire harness from the switch on dash. Followed the directions and worked like a champ.

Exact swap, worked perfectly. No issues at all.