10-4 on the resistor. I really just threw a solenoid on there to see if it made a difference. It appears to be a heat related issue as I am still having failures, and the voltage looked normal.
Toro 640 Valve in heads with about 3 to a zone and 11 zones. So putting elec. valves is not really an option. They are normally open.
Been trying to get them to change them out, but they insist on continuing to fix em.