The Needed 700508 Upper Fan Was Unavailable, and Its Sensor Was Not Separate
The tempting substitute was the available 700507 lower-fan kit. Motor orientation and Hall-sensor integration made that more than a simple propeller swap.
What made the fan model-specific
The Hall sensor was built into the fan assembly and was the reason the assembly was normally replaced as a unit. The upper and lower kits placed the motor differently and did not present an obvious direct interchange.
A similar symptom can have a different cause on another oven. A fan blade, motor winding, sensor, harness or control can each stop convection feedback.
Why the available 700507 kit was not installed by assumption
The technician considered transferring the sensor or adapting the lower-fan assembly. Dacor support reportedly said the arrangement would not work. With the correct 700508 part unavailable and the only secondary-market listing uncertain, the source did not document an experimental installation.
The honest result is a compatibility record, not a fix
This page records the exact model, the two kit numbers and why the proposed substitute was not treated as verified. No repaired fan or restored operation was reported.