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Honeywell RTH6400 Support Question

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Question posted by laertica on December 5th, 2018

Ambient Temperature Display Units

can you change the ambient temperature fron Farenheit to Celcius ?

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Answer #1: Posted by Troubleshooter101 on December 6th, 2018 1:16 AM

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Please check the video tutorial to know How to change thermostat Honeywell from Celsius to Fahrenheit vice-versa

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Related Honeywell RTH6400 Manual Pages

Owner's Manual - Page 1

Quick Installation Guide RTH6400 Series Programmable Thermostat 69-2210EF-03

Owner's Manual - Page 2

Installation is preset for wiring assistance before returning the thermostat to the store. 69-2210EF-03 ii It is Easy Label wires and remove your old thermostat Install and wire your new thermostat Set your new thermostat to help. Call 1-800-468-1502 for the most common system We are here to match your heating/cooling system -

Owner's Manual - Page 4

If so, see back cover for proper disposal instructions. Old thermostat Cover 69-2210EF-03 2 M28099 Leave wallplate in place Is there a sealed tube containing mercury? 2 Remove Old Thermostat Remove old thermostat but leave wallplate with wires attached.

Owner's Manual - Page 6

4 Separate Wallplate from new thermostat. Wallplate M28343 69-2210EF-03 4 Pull here to remove wallplate from New Thermostat Remove battery holder.

Owner's Manual - Page 7

5 Insert Quick Reference Card Insert quick reference card into slot in back of thermostat. M2834 Thermostat M28344 5 69-2210EF-03

Owner's Manual - Page 10

Back of thermostat M28346 69-2210EF-03 8 8 Install Batteries Install two AA alkaline batteries.

Owner's Manual - Page 11

M28347 9 69-2210EF-03 9 Install Thermostat onto Wallplate Install thermostat onto the wallplate on the wall.

Owner's Manual - Page 15

SETUP WIRING ASSISTANCE M28348 Press s or t to exit and save settings. Function 1 Setting 0 Done Next Press DONE to change settings. M28349 Press NEXT to advance to next function. 13 69-2210EF-03 TROUBLESHOOTING RTH6400 ASybsotuetmyosuertunpew thermostat Press and hold the s and FAN buttons until the screen changes (approximately 5 seconds).

Owner's Manual - Page 16

... or electric heating without central air conditioning. (Use this setting if you could turn the fan on and off with a fan switch on your old thermostat.) Press to display next function. When correct setting is selected, press NEXT to change setting. M28351 69-2210EF-03 14 TROUBLESHOOTING

Owner's Manual - Page 17

...M28351 15 69-2210EF-03 SETUP WIRING RTH6400 Function 2: Heat pump changeover valve Press the s or t button to select whether your changeover valve is selected, press NEXT to display next function. When correct setting is ... valve: Use this setting if you connected a wire labeled "B" to change setting. ASSISTANCE TROUBLESHOOTING Press to the O/B W wire terminal (see page 21).

Owner's Manual - Page 18

... setting if you have a gas or oil heating system (system controls fan operation). 1 Electric heat: Use this setting if you have an electric heating system (thermostat controls fan operation). SETUP WIRING Advanced Installation Guide Function 3: Heating fan control Press the s or t button to select your heating system and fan operation: NOTE...

Owner's Manual - Page 19

M28351 17 69-2210EF-03 TROUBLESHOOTING Press to display next function. When correct setting is less than 90...Gas/oil steam or gravity system: Use this setting if you have a steam or gravity heat system. SETUP RTH6400 Function 5: Heating cycle rate Press the s or t button to select your heating system and optimize its operation:... furnace that is selected, press NEXT to change setting.

Owner's Manual - Page 20

... 12: Manual/Auto Changeover Press the s or t button to change setting. When correct setting is selected, press NEXT to option 0 if the outside temperature drops below 50ºF (10ºC). M28351 69-2210EF-03 18 CAUTION: To avoid possible compressor damage, set to display next function. NOTE: System maintains a minimum 3ºF difference between...

Owner's Manual - Page 21

... Next M28356 1 Smart Response® Technology ON 0 Smart Response® Technology OFF NOTE: See Operating Manual for information on Smart Response® Technology. SETUP WIRING RTH6400 Function 13: Smart Response® Technology Press the s or t button to display next function. M28351 ASSISTANCE TROUBLESHOOTING 19 69-2210EF-03 Press to...

Owner's Manual - Page 22

... Installation Guide AFubnocuttioynou1r4n: eTwemthpermatousrteadt isplay Press the s or t button to select Fahrenheit or Celsius temperature display: 14 0 Done Next 0 Fahrenheit temperature display (°F) 1 Celsius temperature display (°C) M28357 Press to exit and save changes. M28351 ASSISTANCE TROUBLESHOOTING 69-2210EF-03 20 When correct setting is selected, press DONE to...

Owner's Manual - Page 23

...heat pump. SETUP WIRING ASSISTANCE TROUBLESHOOTING M28418 If wires will be connected to O/B W. Wrap B wire with electrical tape. 21 69-2210EF-03 RTH6400 Wiring If labels do not use C, X or B. Do not use . Do not connect both R and Rc terminals, remove metal jumper... Wrap bare end of wire with electrical tape and do not match letters on the thermostat, check the chart below ).

Owner's Manual - Page 24

... alkaline batteries are set to match your thermostat, please try the following suggestions. Most problems can be corrected quickly and easily. Display is set to match your heating equipment (see page 16). ASSISTANCE TROUBLESHOOTING 69-2210EF-03 22 Temperature Make sure heating and cooling settings do not temperatures are correctly installed (see page 14...

Owner's Manual - Page 25

...Function 2: Heat Pump issues cool air Changeover Valve to respond. SETUP WIRING Troubleshooting RTH6400 Heating or • Press SYSTEM button to set system cooling system to Cool. ...cool mode ASSISTANCE TROUBLESHOOTING 23 69-2210EF-03 Make sure the temperature does not is set higher than the Inside temperature. • Check circuit breaker and reset if necessary. •...

Owner's Manual - Page 27

...-free at 1-800-468-1502. Battery holder Part No. 50007072-001 Cover plate assembly Part No. 50002883-001 *Use to cover marks left by old thermostats. SETUP ACbuosutotmyoeur ransseiwsttahnecremostat RTH6400 For assistance with this product, please visit http://DIYthermostats.honeywell.com or call Honeywell Customer Care toll-free at 1-800-468-1502.

Owner's Manual - Page 30

Contact your old thermostat in the trash if it contains mercury in U.S.A. Automation and Control Solutions Honeywell International Inc. 1985 Douglas Drive North Golden Valley, MN 55422 ...at least 10% post-consumer paper fibers. ® U.S. Registered Trademark. CAUTION: To avoid possible compressor damage, do not run air conditioner if the outside temperature drops below 50°F (10°C).