Home » Honeywell » Thermostats » Honeywell THM5421

Honeywell THM5421 Support Question

Find answers below for this question about Honeywell THM5421.
Need a Honeywell THM5421 manual? We have 1 online manual for this item!

Honeywell Overview Questions Manuals Reviews Videos Research

Question posted by nchantd1 on December 14th, 2012

How To Test Interface For Thm5421c

The person who posted this question about this Honeywell product did not include a detailed explanation. Please use the "Request More Information" button to the right if more details would help you to answer this question.

I Know the Answer!

I have the same question
Request More Information

Current Answers

There are currently no answers that have been posted for this question.
Be the first to post an answer!

Remember that you can earn up to 1,100 points for every answer you submit. The better the quality of your answer, the better chance it has to be accepted.

Related Honeywell THM5421 Manual Pages

Owner's Manual - Page 2

... Trademark. 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... save these instructions. ® U.S. BE CAREFUL! To prevent damage to press touchscreen keys. This thermostat contains a Lithium battery which may apply, See www.dtsc.ca.gov/hazardouswaste/perchlorate. US Patent No...

Owner's Manual - Page 3

Table of contents VisionPRO® IAQ About your new thermostat Programming at a glance 2 Quick reference to controls 3 Quick reference to status display......... 4 ...control 17 Ventilation control 19 Appendices Advanced functions 20 In case of difficulty 27 Limited warranty 29 This thermostat is below 50˚F (10˚C). 1 69-1815EFS-06 To prevent possible compressor damage, do...

Owner's Manual - Page 4

... See pages 17-19 ONE-TOUCH TEMP CONTROL: You can override the program schedule at 10 pm See pages 8-11 5. Operating Manual About your new thermostat Your new thermostat is pre-programmed and ready to Heat See page 7 4. Select system setting: Preset to go to Auto See page 6 3.

Owner's Manual - Page 9

... 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. • Auto: Thermostat automatically selects heating or cooling depending on the indoor temperature. • Em Heat (only...

Owner's Manual - Page 10

This thermostat is pre-set to adjust times and temperatures of each time period.) Wake (6:00 am) Leave (8:00 am) Return (6:00 pm) Sleep (10:00 pm) ...

Owner's Manual - Page 15

...or UV lamp. Southern Away Dehumidification: Your system may be programmed to Auto, the thermostat automatically selects heating or cooling depending on screen. Special features VisionPRO® IAQ Auto...Before you are away. (If this feature. Adaptive Intelligent Recovery: This feature allows the thermostat to "learn" how long the furnace and air conditioner take to prevent equipment damage....

Owner's Manual - Page 17

... use the damp cloth to resume normal operation, or press SCREEN again if you can clean the screen without changing any liquid directly on the thermostat. Use water or household glass cleaner. The screen will remain locked for 30 seconds so you require more time for cleaning. Avoid abrasive cleansers. After...

Owner's Manual - Page 18

... current outdoor temperature 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 If an indoor remote sensor is displayed. If more than one indoor sensor is installed, the display shows...

Owner's Manual - Page 19

Once frost no longer appears, the thermostat will not be displayed. 17 69-1815EFS-06 Press DONE to save & exit 5 FROST DEHUMIDIFIER 55 CANCEL Press MORE until the humidifier screen is displayed, ...

Owner's Manual - Page 20

.... Note: Auto/Off only present when using a whole house dehumidifier (not present when dehumidifying with A/C). 69-1815EFS-06 18 If installed to control a dehumidifier, the thermostat can activate it as 3°F lower than your temperature setting). Press DONE to save & exit CANCEL Press MORE until the dehumidifier screen is displayed, then...

Owner's Manual - Page 21

... ventilation timer. To turn off the ventilator, select 0. Press DONE to save & exit VisionPRO® IAQ You can still be requested by the installer, the thermostat will turn off /on the automatic ventilation only. Ventilation can ventilate your home as needed. Ventilation control Press to set ventilation timer AUTO DONE 40...

Owner's Manual - Page 24

Thermostat is non-programmable. 4 Program schedule is on or off: Options: 0 Program schedule is lighted: 0 Light on for approx. 45 seconds after keypress 1 Light always on ...

Owner's Manual - Page 25

...; IAQ Temperature format (°F/°C) Function 0320 Press s/t to set the temperature display format: Options: 0 Fahrenheit 1 Celsius Daylight savings time on/off Function 0330 The thermostat is pre-programmed to automatically adjust to daylight savings time (2007 and beyond, for areas that use the new 2007 DST calendar) 23 69-1815EFS...

Owner's Manual - Page 29

... to 32°C) • Cool: 50° to 99°F (10° to make sure the thermostat is closed securely. "Err" appears on . • Make sure furnace door is not locked (see page 26...37°C) Backlight is dim • A dim display is on screen • Contact your thermostat, please try the following suggestions. Most problems can be corrected quickly and easily. In case of ...

Owner's Manual - Page 30

... the Inside temperature. Make sure the temperature is set system to Heat. Wait 5 minutes for "On" during this period (see page 13). Auto indicates the thermostat is following the programmed fan setting. Operating Manual In case of difficulty Heating or • Press SYSTEM to set cooling system higher than the Inside...