Common Questions How do I diagnose a failing Lennox 18G89 Flame Sensor

Does it include the harness

Advanced Diagnostics: Features on-board LEDs to provide HVAC troubleshooting codes

Environmental Resilience: Encased in a corrosion-resistant aluminum housing to prevent failure in high-humidity outdoor condensers

Specifically engineered for integration with Selectra Series 20

Lochinvar & A.O. Smith 100110973 Switch 318423-701 Common Questions How do IThe Lochinvar & A. O. Smith 100110973 Blocked Flue Switch is a critical safety component designed for high efficiency boilers and commercial water heaters. As a veteran technician knows, this negative pressure switch (often referred to as a spill switch) is engineered to sense obstructions in the venting system, protecting the heat exchanger from hazardous flue gas recirculation. When the integrated sensor detects a lack of proper draft or a blocked