Shown are Danfoss Zone Valves
Used in High Pressure Humidification Pumps
for Multiple Zone Applications
Danfoss 3/2 zone valves include a drain valve. In the event of malfunction due to debris, the valve can be taken apart and cleaned.
Rinse it as thoroughly as possible, and purge with air if available. After being cleaned of potential debris, it should be free to open/close 100%.
Images showing the 3/2 valve disassembled to demonstrate the several orifices that should be cleaned.