Hi sir;
Please the valve is S24 is the side of Feeder, measure +24Vdc, betwe conector XS 24 1;3 +xs24;4 +24Vdc.
see if there are loose wires, or broken wires, or lack of Voltage, if NOT voltages, you must track back, where is the Voltage is missing, or the Winding of Valve is Reheating or...