Lennox 43K53 Flame SensorLennox 43K53 sensor flame system delivers precise flame detection and enhanced furnace safety. Powered by sensor flame technology, the Lennox 43K53 continuously monitors ignition and flame presence to reduce outages and protect your home. Designed for reliable operation in gas furnace setups, this component supports fast ignition, early fault detection, and seamless compatibility with Lennox systems. It helps minimize fuel waste by confirming flame

Constructed for durability

factory pre-charged air at 50 PSIG

UL and CE approvals

this unit delivers versatile installation for standing pilot applications

a reliable safety device that protects boilers from damage by detecting low water levels and automatically stopping operation

UL/CE approved for global compliance and reliability

pair with compatible Honeywell controllers and standard thermostats

Operating at 24 V DC

Long stroke

It operates over a wide range from 12 to 60 inches water column (12-60" wc) or 30-150 mbar

Engineered for 240V operation

the RM7845A1001 combines flexibility with robust safety features and scalable control options