When temperatures exceed the 115°F threshold

it must be paired with high-temperature actuators (such as the AG or AH series) specified for steam service to prevent seal failure

If the blower is operational but there is no heat rise

dielectric failure or cracked ceramic on an OEM Raypak ignitor wire often leads to "Main Ign Failure" codes or persistent sparking without ignition

Johnson Controls P170DA-400 Pressure Control 30067439-890 When temperatures exceed the 115°FThe Johnson Controls P170DA 400 Pressure Control is a heavy duty high pressure cutout switch engineered for critical over pressure protection in commercial refrigeration and HVAC systems. As a manual reset pressure control, it provides a hard lockout when system pressures exceed the technician defined setpoint, preventing compressor damage and ensuring a thorough inspection before the system returns to service. This SPST high pressure control features