Bosch 8733953645 Electronic Control Box Subassembly

- Serves as the central control module for compatible HVAC systems.

- Converts sensor and control inputs into switched outputs for fan, pump, and heating operation.

- Ships fully assembled with the populated circuit board mounted to a formed galvanized steel chassis.

- Includes a numbered three-position terminal block with a separate earth terminal.

- Provides onboard relays for switching connected loads.

- Features an EMI line filter choke for electrical noise suppression.

- Offers keyed connectors designated for AC fan, DC fan, pump, and water circuits.

- Equipped with DIP switches for model and application configuration during setup.

- Mounts to the same bracket points as the original assembly.

- Alternate part number 8-733-953-645.

The Bosch 8733953645 Electronic Control Box Subassy is the central command module for compatible HVAC systems, taking in line power and translating sensor and control inputs into switched outputs that drive the unit's fan, circulation pump, and heating functions. It ships as a fully assembled unit with the populated circuit board already fastened to a formed galvanized steel chassis and wired to a numbered three-position terminal block with a separate earth terminal, so incoming power and control conductors land exactly where the original wiring calls for and the whole assembly mounts back into the same bracket points as the part it replaces. Onboard relays, an EMI line filter choke, and clearly designated connectors for the AC fan, DC fan, pump, and water circuits keep each harness keyed to its correct position, while a bank of DIP switches lets the installer configure the board for the specific model and application before start-up. Supplied complete rather than as a bare board, it removes the need to transfer components or rebuild wiring during a service call, shortening downtime on repairs where the existing control has failed.