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The RT1 is a digital countdown timer rated for 120Volt 600 watts
.1) You need to consider the wattage of your jacuzzi circuit
If circuit operates a motor, then check the nameplate on that motor for wattage.
The RT1 is too lightweight for 756Watt 1HP motor.
The RT1 will not work on a 240Volt circuit.
If the circuit operates lights only, then add up the wattage of your bulbs.
The Pass-Seymour site does not have a manual for the product that describes the intended purpose of the timer. For example some timers say 'incandescent only.'2) Understand your wiring so we can get a timer that works
You have a 2 gang box.
The box has a GFCI and no other device.
The GFCI has 4 screws
One cable enters box from breaker box with black and white ... and these wires connect to GFCI
One cable enters box from jacuzzi with black and white ... and these wires connect to GFCI3) If the circuit is 120V
Next we are going to talk about the cable going to jacuzzi.
Disconnect black wire going to jacuzzi.
Timer-black connects where this wire was connected.
Timer-red wire connects to black wire going to jacuzzi
The timer-white connects to the same screw that white-wire-going-to-jacuzzi connects to.
So there are two white wires on one screw.If RT1 is too lightweight
You need a countdown timer rated for the circuit.
Intermatic makes a spring-wound FD series countdown timer that is rated for 2 HP
The Intermatic FD series timers can also be used if jacuzzi is 240Volthttp://www.intermatic.com/products/timers/in-wall%20timers/decorator%20spring%20wound%20timers.aspx
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