Liquid level sensors

[fisherlandon]

I am looking for the liquid level sensors that protect my HLT and BK heating elements, I have 1/2" NPT holes to intall them. I am confused on which to buy

[gitchegumee]

You are right to protect your electric elements with a switch. In electrical parlance, this is called a permissive. I'd use a float switch. Easy to find in 1/2" NPT. Use the switch in series on your start control circuit. The float should be covered before the contacts close and allow the heat to be applied. You would also want a timer relay. This keeps the float from quickly turning the circuit on and off. Good move. Good luck!