Pentair Solar Touch controller

chiefwej

LifeTime Supporter
TFP Guide
Jun 12, 2011
3,396
Tucson
I currently have a solar heating system that has a controller with about a 10 degree variance. If your house thermostat worked like this thing, you would take a sledgehammer to it. The setting that turns on the heat at 79 wont turn off until its over 90. I'm looking for a digital controller with a much finer (2 or 3 degree) variance.

The pentair solar touch seems like an affordable option. I'm wondering if any forum members have any experience with this unit.
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,879
Silver Spring, MD
Nearly all of the solar controllers let you adjust the temperature range they cycle over. Or your current water temperature sensor might be mounted in the wrong place.

The Hayward GL-235 is the best of the inexpensive solar controllers. The Pentair is also good, but noticeably more expensive, though it also does more.
 

chiefwej

LifeTime Supporter
TFP Guide
Jun 12, 2011
3,396
Tucson
My current control is a Helio-Matic HM500D.. It only has a knob to adjust the temp and a three position slide switch, marked "test-on", "auto" and "off". The knob had markings from 70 to 95 and the instruction booklet says to calibrate use the set screw on the knob. No very high tech. Turning the knob I can see how far it is before I hear the relay click to turn it on and how far it is to hear it turn off and it's well over 10 degrees. The people who installed the system have replaced the controller twice,(due to a different problem) but I have never been satisfied with the lack of control over water temp.

One reason I was considering the pentair unit was it is set up to control a VS or VF pump, if I decide to upgrade to one of their pumps in the future.

I can get the pentair for under $250 including sensors and a three way valve with actuator. The price seems to be similar for the Hayward. Since I would only save about $40-50 buying the controller only, I thought it worth the extra to have spare sensors and actuator.