Can anyone direct me to the code reference that requires the bonding of the hot water heater when installing a hydro massage tub?

Also if the tub has a front panel that is removable for servicing the interior parts of the tub, does that make the GFI receptacle you’re installing for the motor accessible?

I am in Central Jersey, with hot tubs, the AHJ may require you to bond the pipes, and if you don't check the load, and additional load is needed, they may want the service upgraded, we had one job in sayreville where they wanted the listing information for a tub, the tub was not listed, you have to look at everything when doing hot tubs.

If you have to remove screws from a cover, it is accessable, but not ready access.

Need to know what you are dealing with. Is it a Hydro-Massage Bath tub or a Spa.Two different items and two different articles in the code book.

From what I see it depends on the inspector if its considered accessible. I agree with this ..
'If you have to remove screws from a cover, it is accessable, but not ready access.'

Who knows if the inspector feels the same.

And the hot water should be bonded. Usually at the hot water heater.

A Hydromassage bathtub, which is something you would find in a master bathroom, falls under section VII of article 680. Spas and Hot Tubs can be found in section IV of article 680 and there is a section for indoor and outdoor type tubs. Although code permits installing GFCI receptacles at the cord connection where the motor is, a more professional installation would be to install a faceless GFCI device above the switches in the room where it more convienent to the end user when the device trips and needs to be reset. I'd say close to 70% of homeowners wouldn't think to check inside their tubs for a tripped GFI.