Here is an example of very poor design on the current boiler I have.
The EBM Papst blower control board which is mounted on the motor it controls is in a hostile environment. This PCB could easily have been placed in the more isolated electronics compartment where the main controller is...
A Burnham Freedom condensing modulating boiler that I own personally has an EBM Papst blower module (BG36RG128) within. The failure mode is that the controlled blower motor intermittently fails to start. The fault has been attributed (by Burnham Tech Support and EBM Papst) to the motor control...