This Marley thermostat is verified for use with QMark and Berko models DH1521D

allowing for precise setpoint selection in the field

Integrating a new Lennox condenser motor bracket during a motor swap is a best practice to maintain factory-spec stability and maximize the operational lifespan of the replacement motor

Designed for high-cycle applications

Maxitrol MR510-3/4 Valve 30067439-890 This Marley thermostat is verifiedThe Maxitrol MR510 3 4 is a professional grade 3 4" NPT Modulating Gas Valve designed for precision fuel regulation in atmospheric burners. As a critical component of the Selectra Series 20 electronic gas flame modulation system, this valve provides a linear relationship between control signals and flow rates, ensuring stable discharge air temperatures. Engineered for indirect fired units, it handles a 1 2 PSI maximum inlet pressure and functions as