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Question posted by jonsan427 on December 12th, 2011

Honeywell Th9421c Cannot Raise Or Lower Temp. Screen Unlocked

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Related Honeywell TH9421 Manual Pages

Owner's Manual - Page 2

.... D509151 and other patents pending. BE CAREFUL! Never use sharp instruments, such as a pencil or pen, to the thermostat, always press keys with this product please visit http://yourhome.honeywell.com or call Honeywell Customer Care toll-free at 1-800-468-1502 Read and save these instructions. ® U.S. To prevent damage to press...

Owner's Manual - Page 3

...preprogrammed and ready to go ! Table of contents VisionPRO® IAQ About your new thermostat Programming at a glance 2 Quick reference to controls 3 Quick reference to status display......... ... schedules 9 Program schedule overrides 10 Vacation hold 12 Special features 13 Screen lock 14 Screen cleaning 15 Optional remote sensors 16 Humidity control 17 Ventilation control 19 ...

Owner's Manual - Page 4

Operating Manual About your new thermostat Your new thermostat is pre-programmed and ready to go to bed at 10 pm See pages 8-11 5. Just set the time and day. Set clock...See page 5 2. Set humification, dehumidification & ventilation controls, if applicable See pages 17-19 ONE-TOUCH TEMP CONTROL: You can override the program...

Owner's Manual - Page 5

... THU FRI SAT SUN OK TO PICK MULTIPLE DAYS 70 FAN Inside AUTO 70 Set To SYSTEM HEAT 6:01 AM Following Schedule SCHED HOLD CLOCK SCREEN MORE VisionPRO® IAQ Press to adjust temperature settings (see pages 9-11) Press for more options Press to override program schedule (see pages 10-11...

Owner's Manual - Page 6

... Inside AUTO 70 Set To SYSTEM HEAT 6:01 AM Following Schedule Recovery 55 Humidity SCHED HOLD CLOCK SCREEN MORE Other display messages: • Cool On: Cooling system is activated • Heat On: ..., the outdoor temperature is shown instead of the humidity level. Press MORE to unlock 69-1815EFS-06 4 Temperature setting Program schedule on (does not display when off) Adaptive Intelligent Recovery ...

Owner's Manual - Page 7

... savings time, and stores all date/time information. WED Clock setting 70 FAN Inside AUTO 70 Set To Press CLOCK 6:01 AM SCHED HOWLEDD CLOCK SCREEN MORE 70 70 FAN Inside Set To AUTO Adjust time, then press DONE 6:02 AM DONE CANCEL VisionPRO® IAQ To set the current time...

Owner's Manual - Page 8

... information). 69-1815EFS-06 6 Operating Manual Fan setting WED 70 FAN Inside AUTO SYSTEM HEAT 6:01 AM 70 Set To Following Schedule SCHED HOLD CLOCK SCREEN MORE Press FAN Note: If a fan schedule is on . • Auto: Fan runs only when the heating or cooling system is programmed, "Auto" will remain...

Owner's Manual - Page 9

... AUTO SYSTEM HEAT 6:01 AM 70 Set To Following Schedule SCHED HOLD CLOCK SCREEN MORE Press SYSTEM VisionPRO® IAQ Press the SYSTEM button to select, then press DONE: • Heat: Thermostat controls only the heating system. • Cool: Thermostat controls only the cooling system. • Off: Heating and cooling systems are off...

Owner's Manual - Page 14

... temperature 70 FAN Inside AUTO 55 Set To SYSTEM HEAT Hold Temperature Until 6:00PM SCHED HOLD CLOCK SCREEN MORE WED CANCEL 2 Press to set the time of day you want , then press s or...Tuole to resume 3 APUrTOess HOLD twice SYSTEM HEAT Hold Temperature Until 14 DAYS SCHED HOLD CLOCK SCREEN MORE CANCEL 4 Press to select number of days 69-1815EFS-06 This feature can suspend the...

Owner's Manual - Page 15

...to prevent equipment damage. After replacement, press RESET to Auto, the thermostat automatically selects heating or cooling depending on screen. Special features VisionPRO® IAQ Auto Changeover: When set . ...is vacant during the humid season. Adaptive Intelligent Recovery: This feature allows the thermostat to "learn" how long the furnace and air conditioner take to help protect...

Owner's Manual - Page 16

... function 0670 (page 26) for several seconds if a locked key is fully locked, no keys function. When partially locked, the screen displays SCREEN LOCKED for screen lock options To prevent tampering, the screen can be partially or fully locked. To lock or unlock the screen, see advanced function 0670 on page 26. 69-1815EFS-06 14

Owner's Manual - Page 17

... changing any liquid directly on the thermostat. SCHED HOLD CLOCK SCREEN MORE 15 69-1815EFS-06 The screen will remain locked for cleaning. Note: Do not spray any settings. WED Screen cleaning FAN 70 70 AUTO Inside SCREEN LOCKED Set To Press SCREEN Following Schedule 6:00PM SCHED HOLD CLOCK SCREEN MORE Screen lock timer (30 seconds) 30 OK...

Owner's Manual - Page 18

... one indoor sensor is installed, the display shows the indoor temperature at the location of temperature readings from all sensors or an average between the thermostat and the sensor(s). 69-1815EFS-06 16 Operating Manual Optional remote sensors WED 70 FAN Inside AUTO SYSTEM HEAT 6:01 AM 70 Set To Following...

Owner's Manual - Page 19

...fogging windows and without saving changes. Once frost no longer appears, the thermostat will not be displayed. 17 69-1815EFS-06 Press DONE to save & exit 5 ...Press MORE until the humidifier screen is displayed, then press s or t to set the humidity and Frost Control level. When using Frost Protection, if frost/condensation appears on windows, lower the frost setting. Wait...

Owner's Manual - Page 20

...you don't have a dehumidifier, the thermostat activates the air conditioner to reduce humidity (may cool as much as needed to reduce humidity. Press DONE to save & exit CANCEL Press MORE until the dehumidifier screen is displayed, then press s or ... operation (Auto or Off). If installed to control a dehumidifier, the thermostat can activate it as 3°F lower than your temperature setting).

Owner's Manual - Page 21

You can still be requested by the installer, the thermostat will turn off /on the automatic ventilation only. Ventilation can set the ventilation timer. Auto/Off will ventilate your home at any time: Press MORE until the ventilation screen is displayed, then press s or t to set the timer to ventilate from 20 to...

Owner's Manual - Page 24

... change 1 Restore factory default Energy Star settings Backlight Function 0280 Options: Press s/t to turn the program schedule on or off: Options: 0 Program schedule is off. Thermostat is non-programmable. 4 Program schedule is lighted: 0 Light on for approx. 45 seconds after keypress 1 Light always on low intensity, full bright after keypress 69...

Owner's Manual - Page 28

..., Sleep) Clock format Function 0640 Press s/t to set the clock display format: Options: 12 12-hour clock (i.e., "3:30 pm") 24 24-hour clock (i.e., "15:30") Screen lock Function 0670 Press s/t to choose a screen lock setting (see page 14): Options: 0 Screen is unlocked (fully functional) 1 All functions locked except temperature controls and CANCEL key...

Owner's Manual - Page 29

...32°C) • Cool: 50° to 99°F (10° to make sure the thermostat is closed securely. Display is blank • Check circuit breaker and reset if necessary. • Make... sure power switch at heating & cooling system is normal. "Err" appears on screen • Contact your thermostat, please try the following suggestions. In case of difficulty VisionPRO® IAQ If ...

Owner's Manual - Page 30

... is closed securely. • If "Wait" is displayed, the compressor protection timer is normal operation. If Auto and On is shown, the fan is set lower than the Inside temperature. Make sure the temperature is scheduled for the system to restart safely, without damaging the compressor (see page 6). 69-1815EFS-06...