The a/c unit on my roof works fine for cooling, but the heat strips and the fan are not coming on for heating the room

Need more info. Is this a heat pump? If you changed the thermostat out did you add a jumper from R to RH? All the info you can give will help.

No, just have heat strips, the thermostat seems to be working for the a/c, but no power to the heat unit, the thermostat was not changed. Ty

The heat strips and blower is timed on by a heat sequencer inside the unit. You can try to jumper a wire from R to W at the thermostat to see if it works. Do you have a volt meter and know how to use it?

The heat strips and blower is timed on by a heat sequencer inside the unit. You can try to jumper a wire from R to W at the thermostat to see if it works. Do you have a volt meter and know how to use it?

No voltmeter... I noticed this morning that the coils are not heating. The fan motor was hot, also. I had to gently push the fan blade to get it started. Your thoughts? Thank you!

A bad motor run capacitor will give that symptom. Cheap and easy fix.

Bad mtr. Bearings possibly