the 421-661 delivers the precise milliamperage required to maintain the pilot flame across diverse combustion chambers

preventing the buildup of dangerous flue gases

contractors can eliminate external check valve installations

Because these brands fall under the Johnson Controls umbrella

Greenheck 386409 Ignition Control 318518-761 the 421-661 delivers the preciseThe Greenheck 386409 Ignition Control is a critical replacement component engineered for precise flame monitoring and sequencing in high performance makeup air units and commercial HVAC systems. This direct spark ignition (DSI) module provides reliable trial for ignition periods and instantaneous flame sensing to ensure safe burner operation under demanding conditions. Designed to integrate seamlessly with Greenheck gas fired heaters, the 386409