Pressure Switches

Pressure switches are a device that automatically senses a change in your hot tubs water pressure. It is used to provide safety in your spa to prove that there is first water flow before it will turn on the heater relay. So if there is no water flow or even not enough flow, the pressure switch will turn off your heater to keep it from melting anything around the heater area. So your hot tub has to have flow for the pressure switch to be activated! It will turn on with water pressure and turn off with no pressure via the pump power or the water level or by something that could obstruct the flow of water. These switches protect the guts of the hot tub from the heat of the heater. Make sure your pressure switch is marked at the correct PSI for your hot tub. It should be factory adjusted already.