The only problem I’ve had was that I had a valve with a shorted solenoid and that smoked a triac in the OSPi. At Ray’s suggestion, I’ve added a 1-Amp fuse to the ground/common wire. I’ve replaced the shorted solenoid and changed the wiring to now use a spare OSPi channel.
I’ve had both controllers connected in parallel for several weeks now. Now that I’m using the RPi web app with the interval timer daily, the Hunter has been in the off position. The Hunter is only supplying the 26Vac power to the OSPi. I intend to disconnect the Hunter from the OSPi when the Texas heat ends this late 😉 Fall and it becomes somewhat cooler in the garage.