Bathroom fan motors, filters, and the parts that look identical but aren't —
each model gets one page: what fits, what doesn't, and how to swap it.
The model number is stamped on a sticker inside the housing — pull the grille down and look up. Try 688 or 763RLN.
Two parts can look identical and still not fit. Forums are full of "will this work with my…?" — each page below is the single clean answer, verified against manufacturer specs.
It's on the sticker inside the unit — every page shows you exactly where to look for that model.
Confirmed fits and the common mix-ups that don't fit — so you don't order the wrong twin.
Symptom-based diagnosis (is it the motor, or the capacitor?), then a step-by-step swap with the breaker off.
The most-searched bathroom fan models, fully researched:
Three part numbers, one fan — which kit you actually need, plus the 60 CFM upgrade path the old housing allows.
Open the guide →The motor assembly for the NuTone 763RLN series — and why the similar 665 motor is the wrong part for this fan.
Open the guide →