It depends on how your tub initiates a temp
up signal. Do you have the user’s manual to
the tub? Some functions can be controlled by
contact closure on older tubs. On the newer
tubs you might need to integrate a
controller, like the Aqualink, with RS232 or
similar connectivity. This could turn in to a
lengthy discussion and it might be easier if
you stop by AccessHA and post this topic.
Then I could post some images to better
illustrate what’s possible.
www.AccessHA.com