This article explains how to replace batteries of the following thermostats (note the pictures if you do not know the thermostat model):

ADC-T2000 ADC-T2000.png

ADC-T25 ADC-T25.png

Honeywell T6 Honeywell T6 thermostat.png

 

ADC-T2000 Battery Replacement:

Ensure the batteries are installed following the specified polarity markings on the thermostat.

  1. Pull thermostat off the wall to expose the batteries in the back. 
  2. Insert four new AA batteries.
  3. Securely re-attach thermostat to the mounting plate on the wall

 

ADC-T25 Battery Replacement:

  1. Remove the thermostat from the wall plate by pull the thermostat straight out from the wall. This exposes the batteries on the back of the thermostat.
  2. Remove existing batteries.
  3. Insert the new batteries following the specified polarity markings on the thermostat.
  4. Reinstall thermostat securely on the wall against the mounting plate.

 

Honeywell T6 Battery Replacement:

  1. Grasp the thermostat firmly and pull it straight out from the wall plate. Be careful not to bend or break any pins or wires behind it. 
  2. The battery compartment is typically on the back of the thermostat. Remove the old batteries and dispose of them properly, recycling them if possible.
  3. Insert three new AA alkaline batteries, making sure the positive (+) and negative (-) terminals match the markings inside the battery compartment. 
  4. Align the thermostat with the wall plate and firmly press it back into place until it clicks or snaps securely.