Do you have an outdoor temperature sensor connected to the controller? If you do you should see the outdoor temperature displayed. If you don't then I recommend you have it installed.

You need to set the electric heat lockout temperature. This is only going to work if you have an outside sensor. By default the lockout is off. You set it so that whenever the outside temperature is above a specified value the electric heat will not turn on regardless of the room temperature and thermostat temperature setting.

Here is the installation manual. Lock out page 10 to see how to change the lockout setting.

Here is a link that might be useful: Evolution controller installation manual

Thanks very much Mike - your advise was very helpful!

I do have an outdoor temperature sensor and I followed your advise and set up the lockout temperature on the Controller not turn on above 30 degrees Fahrenheit.

I believe that the question still remains, how to make sure that the backup heat does not turn on when difference in target and room temperature is less then 2 degrees. Can you help with that?

Thanks again,

Since you have set the outside temperature to 30 degrees, have you seen the back up turn on when the room temperature differential is less than 2 degrees? As far as I know there is no setting to specify the temperature difference when the backup heat can turn on.

I just changed the settings and, of course, did not have a chance to check it out. I assume that you implied that I would not have this problem anymore. I hope so.

Anyway, I thank you much for your advice

The controller should take into account the outside temperature to decided when the back up is needed to reach the required room temperature. Let it operate for a while and see how it does. I would be interested in knowing the results.

I would post the results. Thanks, Mike, for your help again