My Whirlpool ciello only has a 2 prong plug. How do I ground the tub?

You can go to any metal part of the tub or electrical part (motor - valve - connection) and fasten a ground wire to that part using a nut and bolt or screw. I would suggest you use a screw that is already on the motor. Run the ground wire to a known good ground. The ground doesn't necessarily have to be the electrical outlet (a cold water piper, for example). There is that possibility that there is nothing metal that you will find exposed. That makes it a little tougher. If this tub came this way from the manufacturer (two prong plug), it is probably exempt from the grounding requirement. I would suspect that the manufacturer wants you to plug this device into a GFI. You can get a GFI at any store that sells electrical parts. A separate ground is NOT required for full protection when using a GFI. All consumer grade GFI (they look like a regular, rectangular outlet) come ready to accept a three prong plug and there will be a place to fasten your house wire ground to the device. As I said, the ground it not a requirement for correct and complete function of the device. If you don't have a GFI available where you are connecting the plug, change it or get a qualified electrician to change it for you. DO NOT, UNDER ANY CIRCUMSTANCES, PLUG THIS DEVICE INTO A STANDARD OUTLET . Use it only on a GFI protected circuit. The outlet you are considering may already be protected by a GFI breaker. You can only prove this by finding the breaker, turning it off and checking the outlet in question. If it is a GFI breaker, it will look different from the others - and have a test button on it. If you are unsure, replace it with a new GFI breaker. I suppose I should also say here that you should check with yout town building inspector as to the requirements before you proceed, so you will meet any local code requirements. If you live in North America, I am certain the GFI is a requirement for this installation, as the National Electrical Code requires it, (Canada and USA).

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