Honeywell RTH2510/RTH2410 Series - In case of difficulty; Troubleshooting Blank Display; System Not Responding

Operating Manual
69-2725ES—03 20
If you have difficulty with your thermostat, please try the following suggestions.
Most problems can be corrected quickly and easily.
Display is blank • Makesurefurnacedoorisclosedsecurely.
• MakesurefreshAAAalkalinebatteriesarecorrectlyinstalled(seepage
18).
Heating or cooling
system does not
respond
• SetsystemswitchtoHeat (see page 7). Make sure the temperature is
set higher than the Inside temperature.
• SetsystemswitchtoCool (see page 7). Make sure the temperature is
set lower than the Inside temperature.
• Wait5minutesforthesystemtorespond.
In case of difficulty