Heating controls and components connect to HVAC systems to monitor and regulate the heating components within the system. Furnace control boards connect to heat-generating HVAC components and provide control over their functions. Ignition controls and components monitor and regulate the ignition process in combustion-based heating systems. Fan and limit controls regulate the operation of the blower fan and monitor temperatures to ensure the system does not exceed safe operating temperatures. Hydronic heating controls and components monitor and regulate the functions of boiler-based heating solutions that heat water and use radiators to heat a space.