790-015 Robertshaw Direct Spark Ignition

The RAM hot surface ignition controls are 24V AC. When the thermostat calls for heat, RAM's HSI control simultaneously energizes the hot surface ignitor and initiates current sensing function. Gas valve(s) remain closed until current sense threshold is reached. Once the current draw threshold has been reached or exceeded, the gas valve(s) and flame rectification circuits are energized. Upon proof of flame, the hot surface ignitor is shut off. Main burner flame is continuously monitored. Loss of flame detection results in RAM-H cycling to check the current draw of the hot surface ignitor. If the hot surface ignitor is below the current draw threshold, the gas valve(s) will remain off and the hot surface ignitor will remain on until the current threshold is reached.