Switch 24v AC Solenoid with relay - What Snubber values?


I built a wireless ultrasonic water tank meter which is working well, I recently added a relay driver to switch on and off a 24v AC solenoid on my sprinkers. This works but every now and then, when turning off crashes the micro (uno)...

I have researched and now know I need a snubber or a a triac based driver.

Since my relay driver is in place already I figured adding a snubber would be easiest but not sure about the values to use? Has anyone done this before?

Refer to: https://forum.arduino.cc/index.php?topic=126901.0

I think in order to make suggestions, more Needs to be known about the relay you are using. What are the Ratings?


Relay is this one https://www.jaycar.com.au/arduino-compatible-5v-relay-board/p/XC4419

Resistance accross the solenoid is 35 ohms.