Lennox 99K31 Relay 318172-701 Optimized Airflow: The 22-degree pitch

Optimized Airflow: The 22-degree pitch is calibrated to maximize CFM output while keeping the condenser fan motor within its rated amperage

Use a multimeter to check for continuity across the coil and the normally open contacts

which is the direct replacement for the legacy part number 97730

provided it is installed in a well-ventilated area per local mechanical codes

making it perfect for fail-safe cooling or venting applications

Lennox 99K31 Relay 318172-701 Optimized Airflow: The 22-degree pitchThe Lennox 99K31 relay is a critical OEM replacement component designed specifically for managing blower motor operations in Lennox residential furnaces and AHUs. Rated for a 2. 5 4. 0 AMP load, this SPNO (Single Pole Normally Open) relay ensures reliable low voltage control over high voltage circuits. Field technicians prioritize the 99K31 for its precise 24V coil voltage compatibility, which prevents common failures like relay chatter or pitted