Quote Originally Posted by Erikamc View Post
please explain what "proportional thermostat" means.
A proportional thermostat constantly adjusts temp, thus keeping a constant temp. Non proportional will come on and off usually at a variance of a couple degrees, thus creating temp swings. If you set a non proportional to say 85 degrees, it might not come on until temps fall to 83 and not shut off until it hits 87. Proportional will maintain a steady 85.