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Thermostat Types
LCD Display
Wall Mounted
User Interface Type
Push Button
Ease of Installation
Intermediate (Installs < 60 minutes)
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Conserve Energy by Running Your Thermostat Only at Pre-Set Times
Honeywell RTH2510B1000/A 7 Day Programmable Thermostat
Honeywell RTH2510B1000/A 7 Day Programmable Thermostat
Honeywell RTH2510B1000/A 7 Day Programmable Thermostat
Item# 20501
Price: Normally $79.99 
Hot Deal $45.46
Free shipping on orders over $175 - See Details


  • Simple programming for each day of the week
  • Basic operation with precise temperature control of +/-1° F to maximize comfort.
  • Energy Savings and Early Start Function
  • Compatible with heating and cooling plus heat pump systems
  • Backlit display is easy to read, even in dimly lit rooms and hallways
  • Display options are in ° C or ° F temperature, 12 or 24 hour clock
  • Sleek one-piece design

Essential Info

The Honeywell RTH221B1021/A 5-1-1 Day Programmable Thermostat is designed to provide you with push-button climate control, with advanced programming schedules to save energy, while offering the reliability to give you many years of service. In contrast to Non-Programmable thermostats which simply allow you to select a setpoint temperature and turn the thermostat to cool or heat, a Programmable thermostat allows you to create schedules for automatically running your cooling or heating system a certain times. A 7 Programmable Thermostat is best if you tend to have varied schedule that requires a different schedule for each day of the week. The thermostat is pre-programmed with a set schedule; however this is easily modified to fit your lifestyle. You can even temporarily ignore the programmed schedule by using the up or down arrow buttons to adjust the temperature. There is a battery backup, two AAA batteries required (sold separately), that will maintain your setpoint even if you lose power; a low battery indicator displays when the batteries need to be replaced. A built-in compressor protection feature helps prevent damage to the compressor in your air conditioning or heat pump system which can occur if the compressor is restarted too soon after shutdown.

Energy Savings - Programming can save up to 33% on annual heating and cooling costs (if used as directed. Savings may vary depending on geographic region and usage).

Early Start: This feature allows the heating or cooling to turn on before the program start time, so the temperature is reached at the time you set. For example: Set the Wake time to 6 am, and the temperature to 70° F. The heat will come on before 6 am, so the temperature is 70° F by the time you wake at 6. The next time period is displayed when the system is activated before a scheduled time period.

This thermostat is compatible with the following systems:
• Gas, oil or electric furnace
• Central air conditioner
• Hot water system with or without pump
• Millivolt system
• Central heating and cooling system
• Heat pump without auxiliary/backup heat

Please Note: This thermostat does not work with electric baseboard heat (120V-240V) and multi-stage heating/cooling systems


What's Included

  • 1x - Thermostat
  • 1x - Wall Plate
  • 1x - Set of Mounting Hardware
  • 1x - Set of Wire labels
  • 1x - Quick-Start Guide
  • 1x - Owner's Manual
  • More Info

     Pre-Programmed Factory Schedule Settings
     Period  Start Time HeatCool
    Wake6:00am70° F (21° C)75° F (24° C)
    Leave8:00am 62° F (16.5° C)  83° F (28.5° C) 
    Return6:00pm70° F (21° C)75° F (24° C)
    Sleep10:00pm62° F (16.5° C)78° F (25.5° C)

    These settings can be modified at any time to fit with your schedule. It’s easy to program your system for maximum energy savings. You can program four time periods each day, with different settings for weekdays and weekends.
    WAKE - the time you awaken and the temperature you want in the morning, until you leave for the day
    LEAVE - the time you leave home and the temperature you want while you are away (energy-saving level)
    RETURN - the time you return home and the temperature you want during the evening, until bedtime
    SLEEP - the time you go to bed and the temperature you want overnight (energy-saving level)


    Manufacturer Product No.RTH2510B1000/A
    Heating Range40° F to 90° F (4.5° C to 32° C)
    Cooling Range50° F to 99° F (10° C to 37° C)
    Operating Ambient Temperature32° F to 122° F (0° C to 50° C)
    Operating Relative Humidity5% to 90% (non-condensing)
    Backup Power2x AAA batteries
    Manufacturer Warranty1-year limited



    Sony Alkaline AAA batteries       
    Sony Alkaline AAA batteries       

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