Honeywell RTH7400/RTH7500 Series Programmable Thermostat
Quick Start Guide
Installation is Easy
This thermostat is designed to work with virtually all heating and cooling system types and comes preset for the most common configurations. For wiring assistance, call 1-800-468-1502 before returning the thermostat to the store.
Important Note: This thermostat works on 24 volt or 750 mV systems. It will NOT work on 120/240 Volt systems.
Installation Steps
Step 1: Turn OFF Power
Turn off the power to your heating and cooling system at the circuit breaker or system switch.
Step 2: Remove Old Thermostat
Carefully remove your old thermostat from the wall. Leave the wallplate with wires attached. If your old thermostat contains a sealed tube with mercury, please refer to the back cover for proper disposal instructions.
Mercury Notice: Do not place your old thermostat in the trash if it contains mercury in a sealed tube. Contact the Thermostat Recycling Corporation at www.thermostat-recycle.org or 800-238-8192 for information on how and where to properly and safely dispose of your old thermostat.
Step 3: Label Wires with Tags
Using the supplied wire labels, label each wire according to the terminal it was connected to on the old thermostat. Then, remove the old wallplate.
Common Wire Labels: R, Rc, Rh, C, W, W1, W2, Y, Y1, Y2, G, O/B, E, Aux, L.
Step 4: Separate Wallplate from New Thermostat
Gently pull the new thermostat body away from its wallplate to separate them.
Step 5: Mount Wallplate
Position the new wallplate on the wall and secure it using the included screws and anchors. Drill pilot holes as needed: 3/32-inch for plaster, 3/16-inch for drywall.
Step 6: Connect Wires
Match each labeled wire to the corresponding terminal on the new wallplate. Insert wires into the terminal holes and tighten the screws to secure them. For conventional systems, the terminals typically include R, Rc, W, Y, G, W2, Y2, C.
Wiring Diagram (Conventional System Example):
Terminal Wire Label R R Rc Rc W W Y Y G G W2 W2 Y2 Y2 C C Important Notes:
- Remove the metal jumper connecting R and Rc terminals if you have separate R and Rc wires.
- Wire colors may not always match the terminal labels.
- If you have a Heat Pump system, refer to the specific wiring notes.
- Call 1-800-468-1502 for wiring assistance if labels don't match or if you have a Heat Pump system.
Step 7: Install Batteries
Install two AA alkaline batteries into the thermostat and remove any protective tab.
Step 8: Install Thermostat onto Wallplate
Align the thermostat with the wallplate and gently push it until it clicks into place.
Step 9: Turn Power Back ON
Restore power to your heating and cooling system at the circuit breaker or system switch.
Step 10: Set Time and Date
Use the [up] and [down] buttons to set the current Month, Day, and Year. Press NEXT to advance to the next setting. Use the buttons again to set the current Time. Press DONE to save and exit.
Example Settings: Month: 6, Day: 15, Year: 2012, Time: 10:10 AM/PM.
Step 11: System Type Confirmation
If your system type is Single Stage Heat and Cool, your thermostat is now set up. For other system types (Multistage Heat/Cool, Heat Pump, Heat Only, Cool Only), continue to Step 12a to configure your system.
Definition: A Heat Pump is an air conditioner that provides cooling in the summer and runs in reverse in the winter to provide heating.
Step 12a: System Setup
To configure your system settings, press and release the left button, then press and hold the center button until the screen changes (approximately 5 seconds). Use the [up]/[down] buttons to change settings, NEXT to advance to the next function, and DONE to save and exit.
Functions and Settings:
- 0120 Year Setting (first two digits): Set to '20' for 20xx or '21' for 21xx.
- 0130 Year Setting (second two digits): Enter the last two digits of the current year (e.g., '12' for 2012).
- 0140 Month Setting: Enter the current month (01-12).
- 0150 Date Setting: Enter the current day (01-31).
- 0170 Select System Type: Choose the option that best matches your heating and cooling system (e.g., Gas/oil heating with central AC, Heat pump without backup, Heat only, Cool only, etc.).
- 0180 Heating Fan Control: Select '0' for Gas or oil heat (system controls fan) or '1' for Electric heat (thermostat controls fan).
- 0190 Heat Pump Changeover Valve: Select '0' if your heat pump uses an 'O' wire for cooling changeover, or '1' if it uses a 'B' wire for heating changeover.
- 0240 Heating Cycle Rate: Adjust how frequently the heating system cycles to maintain temperature. Recommended settings are 5, 9, 3, or 1.
- 0270 Emergency Heat Cycle Rate: Adjust cycle rate for emergency heat on heat pump systems.
Note: Some functions may not appear depending on your thermostat model or previous selections.
Step 12b: Preferences (Optional)
You can adjust display and operational preferences using the same navigation steps as System Setup.
Functions and Settings:
- 0300 Manual/Auto Changeover: '0' for manual (you set Heat/Cool/Off), '1' for automatic (thermostat switches based on temperature).
- 0320 Temperature Format: '0' for Fahrenheit (°F), '1' for Celsius (°C).
- 0330 Daylight Saving Time: '0' for Off (no automatic adjustment), '1' for On (pre-2007 DST calendar), '2' for On (2007 and later DST calendar).
- 0500 Furnace Filter Change Reminder: Set a reminder for filter replacement (Off, 1 month, 3 months, 6 months, 9 months, 1 year, 3 years).
- 0530 Smart Response® Technology: '1' to enable adaptive learning for comfort, '0' to disable.
- 0600 Maximum Heat Temperature Limit: Set the highest desired heating temperature (default 90°F, adjustable 40-89°F).
- 0610 Minimum Cool Temperature Limit: Set the lowest desired cooling temperature (default 50°F, adjustable 51-99°F).
- 0640 Clock Format: '12' for 12-hour clock (e.g., 3:30 PM), '24' for 24-hour clock (e.g., 15:30).
Wiring Notes
Conventional System Alternate Wiring
- Remove the metal jumper connecting R and Rc terminals only if you must connect both R and Rc wires.
- If your old thermostat had both R and RH wires, remove the metal jumper. Connect the R wire to the Rc terminal and the RH wire to the R terminal.
- If your old thermostat had only one C or C1 wire, connect it to the C terminal. If it had two C or C1 wires, wrap each separately with electrical tape and do not connect them.
Heat Pump System Wiring
Connecting Wires: Match each labeled wire with the same letter on the new thermostat. Use a screwdriver to loosen screws, insert wires, and tighten. If E and Aux terminals do not have wires connected, use a small piece of wire to connect them to each other.
Heat Pump System Alternate Wiring:
- Leave the metal jumper in place, connecting R & Rc terminals.
- If your old thermostat had both V and VR wires, contact a qualified contractor for assistance.
- If your old thermostat had separate O and B wires, attach the B wire to the C terminal. If another wire is already attached to the C terminal, contact a qualified contractor.
- If your old thermostat had Y1, W1, and W2 wires, contact a qualified contractor for assistance.
- If the L terminal is used, a C terminal wire must be connected. Contact a contractor if there is no C wire.
- If E and Aux terminals do not each have a wire connected, use a small piece of wire to connect them to each other.
Customer Assistance
For assistance with this product, please visit http://yourhome.honeywell.com or call Honeywell Customer Care toll-free at 1-800-468-1502.
Important Notices
Perchlorate Material Notice: This thermostat contains a Lithium battery which may contain Perchlorate material. Special handling may apply. See www.dtsc.ca.gov/hazardouswaste/perchlorate.
Mercury Notice: Do not place your old thermostat in the trash if it contains mercury in a sealed tube. Contact the Thermostat Recycling Corporation at www.thermostat-recycle.org or 800-238-8192 for information on how and where to properly and safely dispose of your old thermostat.
Caution: To avoid possible compressor damage, do not run air conditioner if the outside temperature drops below 50°F (10°C).
