I had a propane heater removed from the garage and put in radiate heater up. My problem is now I don't remember if the white to the thermostate is the hot or it the red is hot. Please help. Marta

The red is hot. If you need more help, see the sticky at https://www.askmehelpdesk.com/heating-air-conditioning/heating-cooling-maintenance-repair-troubleshooting-frequently-asked-questions-58313.html

The next step from there is to post to the H&C forum.