How do I install this on an existing electrical box

this part will not be compatible

Key Benefits Efficient Auto Changeover: Automatically switches between heating and cooling modes based on ambient demand to maintain consistent setpoints

The Bard HVAC 8406-076BX Door Switch is a heavy-duty SPST (Single Pole Single Throw) component critical for maintaining the operational safety of commercial and industrial HVAC systems

Reznor 211763 Vent Assembly L99H008 How do I install thisThe Reznor 211763 Vent Assembly is a factory engineered horizontal vent combustion air terminal kit specifically designed for Reznor UDAS and UDBS unit heaters. Supporting heater capacities from 150,000 to 400,000 BTUs, this assembly facilitates a clean horizontal wall termination for concentric venting systems. By integrating both the exhaust outlet and combustion air intake into a single penetration, this kit simplifies the installation process and