The Honeywell RTH7500 thermostat controls your domestic heating and cooling system, helping you maintain a comfortable temperature all year round. Locking the thermostat's temperature cancels any heating fluctuations programmed for the day, night or various seasons, instead maintaining a constant temperature within your house 24 hours a day. Canceling the temperature lock resumes normal temperature schedules in your home. Temperature locks help create a temporary environment in your home for special occasions.
Locate the "Up" and "Down" soft buttons to the right of the LCD display on your Honeywell thermostat.
Tap "Up" and "Down" until the desired temperature appears on the display.
Press the button beneath "Hold" on the LCD display. "Permanent Hold" appears on the screen. The thermostat is locked. Pressing the button beneath "Use Schedule" resumes normal thermostat functions.