AutoPilot piping setup question


New member
Apr 28, 2008
Hey all - what a great resource!

I've got less than an 18" section of pipe separating the outflow from the heat pump and the place where the piping separates to flow to the two pool returns.

Of course, I have to do some cut and paste PVC work because my pool piping is 1.5" and the autopilot fixture connections are 2".

This is going to take a touch of creative plumbing...

My question is:

1) Is is better to have the autopilot manifold laid out in a horizontal or vertical orientation? The diagrams seem to show a horizontal setup (as in parallel to the ground), but it's hard to tell with a 2 dimensional diagram.

It would be more convenient for me to install it with a vertical orientation, due to space constraints with current piping.
I do see the caution that says don't install the manifold upside down. I think that means don't orient the manifold so that the tri-sensor hangs below the check valve.

Am I on the right track here?

2) I think I remember someone cautioning against exposing the control box to full sun. True, or no big deal?

3) The chart says I need about 500# of salt to get my 20K gal pool up to 3000ppm. How long will it take this stuff to dissolve? Do I have to add it over several days, or can I just let her rip?

4) Anybody have anything to say about the pros and cons of letting the autpilot act as the pump timer versus keeping my old school mechanical timer?



LifeTime Supporter
Platinum Supporter
TFP Expert
May 7, 2007
Silver Spring, MD
If no automation system is involved it is better to let the AutoPilot control the pump. That gives you a small extra safety factor and allows the prime protect feature work.

You should either measure the salt level in the pool or wait till the AutoPilot is installed and let it measure for you. The salt level is often well above zero, so you usually need less salt than you think.

Salt can be simply dumped in. It will dissolve fairly quickly, say half an hour, but it can take the water a few hours with the pump running to mix to a uniform salt level.

There are two orientations of the manifold that are allowed: pipe horizontal with the loop up/cell vertical/tri-sensor on top, and pipe vertical with the loop to the side/cell on the low side/water flowing down.