Tekmar 279 schedule suddenly stopped working

nybigapple

I had a tekmar 279 installed 2 months ago. It was working exactly as expected up to a few days ago. It started getting really cold in nyc, and I noticed the heat working overtime at night. It is normally programmed with a setback so I was surprised. Now I look at the controls and it shows as occupied even though it is clearly in the unoccupied time. What is going on?

Schedule, 2, 24 hr, 6 am occupied, 10 pm unoccupied. It always shows occupied on the screen and the heat is constantly running. Nothing was changed setting wise recently. It's just the controls. Is there some setting I'm unaware of overruling the schedule because of the low night time temps? Is there a way to reset the schedule?

JohnNY

Do you have a room temperature unit/sensor? I believe that, when installed, the RTU overrides some of the design parameters.