my nutone bathroom model 9905-r02

It's possible that the problem lies with the wiring or the breaker itself, not the heating element or exhaust blower. You should check the wiring for any loose or damaged connections and ensure that the breaker is properly sized for the heating element.

To troubleshoot the issue with your Nutone bathroom fan model 9905-R02 tripping the circuit breaker when the heating element is used:

1. Check the wiring connections to ensure they are tight and secure
2. Test the circuit breaker by resetting it and see if it trips again
3. Verify the amperage rating of the new heating element matches the original one
4. Inspect the exhaust duct system to see if it's clogged or obstructed
5. Test the motor for proper operation and check for any signs of damage or wear
6. If the exhaust blower is not functioning, inspect it for proper operation and check for any signs of damage or wear
7. Consider hiring a professional electrician if the issue persists or if you are not comfortable troubleshooting electrical components.