Solenoid Valve

A while back, I wrote about how to identify restrictions within the fuel system for your EnergyLogic Waste Oil Burner. To add to that discussion, today I’ll explain the function and care of your Solenoid Valve and Nucleus.

The Solenoid Valve is located just above your Preheater Assembly, and is essentially an electric fuel-supply valve. When the Primary Control on your EnergyLogic Heater or Boiler receives the call for heat, several parts are energized including the Metering Pump and Solenoid Valve. When Energized, the Solenoid Nucleus should lift inside its brass housing, allowing fuel to flow into and through the nozzle.

Here we see a Disassembled Solenoid Valve, with the nucleus and spring visible.

Symptoms of Failing Solenoid Valve

• The high pressure reading discussed in my previous post, where the pressure gauge is reading 50-70psi, is a symptom of this solenoid failure.


• Burners reaching thermal reset before achieving burn status


• Excess, un-burned fuel in the burn chamber


• Sometimes, if the solenoid is slow to close, you will see the flame go out slowly when heater turns off as opposed to being almost immediate when the solenoid operates smoothly

Preventive maintenance is the best way to keep your solenoid valve operating correctly. During your annual maintenance, simply remove the solenoid and clean thoroughly, before reinstalling with a new spring and nucleus, as seen here.