Review on 12V Brass Solenoid Valve, 3/4" Electric Air Valve For Water, Air, Gas, Fuel And Oil - Normally Closed By Beduan by Carlos Abood

These DC solenoid valves are NOT rated for continuous duty operation. Operating them in continuous duty service will cause the coils to overheat and fail. The power dissipated by a 12 vdc solenoid in steady-state conditions (12 vdc applied continuously) depends on the DC resistance of the solenoid coil. For example if the DC resistance is approximately 5.0 ohms for the 12 vdc solenoid and with exactly 12 vdc applied the current is 12/5 or 2.4 amps. The power dissipated is voltage drop times the current or 12*2.4 or 28.8 watts. This much power dissipation will overheat the coil and failure will occur. The vendor neglects to tell you in a clear manner this product is not intended for continuous duty operation. The solenoid valve if used properly can be used in continuous duty mode. To do this requires additional circuitry that controls the duty cycle of the solenoid relay. The solenoid requires full voltage and current initially to open the valve and once open the valve can be held open with lower voltage and current. To use this valve in continuous duty you must use an economizer device/circuit. This can be a microprocessor device or specific electronic economizer devices. If your application is continuous duty the best option is not to purchase this solenoid and find one specifically manufactured for continuous duty operation.