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Honeywell RTH221B User Manual

Owner's manual.
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Press to set clock
or schedule
Press to override schedule
and hold temperature
Press to run (follow)
programmed schedule
Display screen
Setpoint indicator
Appears when the setpoint
temperature is displayed.
Low-battery warning
schedule override
Schedule period
When Cool On is flashing, this means the compressor protection is engaged
(see section 1.7).
Setting the clock
Press the Set button. The message Set Time will
appear on the screen and the time display will flash.
Press the  or  button to set the time.
Press the Run button to save the changes & exit.
(The changes are also saved if you do not press any
button for 60 seconds.)
NOTE: The clock has lost its settings when the time display flashes. If
the thermostat is following the programmed schedule, it will use the
temperature settings programmed for the Wake period until you re-
adjust the clock.
System switch
Use the System switch to place the system in one of the following
• Cool: System is in Cooling mode.
• Off: System is off.
• Heat: System is in Heating mode.
Do not use Cooling mode when the outdoor temperature
is below 50 °F (10 °C).
Fan switch
System switch
adjustment buttons
Temporary schedule override
System status
• Cool On: Cooling is activated.
• Heat On: Heating is activated.
Fan switch
Use the Fan switch to select the fan operation.
• Auto: The fan runs only when heating or cooling is actually taking
place (commonly used setting).
• On: The fan runs continuously.
Temperature setting
Press the  or  button once to display the setpoint temperature.
Press either button more than once to change the setpoint.
The ambient (measured) temperature is normally displayed. To view
the setpoint temperature, press either of the temperature adjustment
buttons once. The setpoint temperature will appear for five seconds.
Built-in compressor protection
Your thermostat has a feature that helps prevent damage to the
compressor of your air conditioning system. Because damage can
occur if the compressor is restarted too soon after shutdown, this
feature forces the compressor to wait five minutes before restarting.
During the wait time, the message Cool On flashes on the screen.
When the safe wait time has elapsed, the message stops flashing
and the compressor turns on.
Programmed schedule
Using the schedule
Press the Run button to follow the programmed schedule. You can
have up to four periods in one day. Each period can be programmed
with a different temperature setting.
Morning temperature
Daytime temperature
Evening temperature
Night temperature
To program a period, you need to set its start time and its two
temperature settings (one when the thermostat is in cooling mode
and another one when it is in heating mode). The same period and
settings are repeated every day.
For maximum energy savings without sacrificing comfort, you can
program the schedule such that the temperature is at an economical
level when you sleep or are away during the day and at a comfortable
level when you are awake and at home.
Factory settings
Start time
6:00 a.m.
8:00 a.m.
6:00 p.m.
10:00 p.m.

User Guide

Programmable Thermostat
70 °F (21 °C)
75 °F (24 °C)
62 °F (16.5 °C)
83 °F (28.5 °C)
70 °F (21 °C)
75 °F (24 °C)
62 °F (16.5 °C)
78 °F (25.5 °C)


   Summary of Contents for Honeywell RTH221B

  • Page 1: User Guide

    RTH221 User Guide Programmable Thermostat Fan switch  Operation Use the Fan switch to select the fan operation. Controls • Auto: The fan runs only when heating or cooling is actually taking place (commonly used setting). • On: The fan runs continuously. Press to set clock or schedule Fan switch...
  • Page 2: Modifying The Schedule

    This warranty does not cover removal or reinstallation costs. This warranty shall not the programmed schedule. The word Hold will disappear and the apply if it is shown by Honeywell that the defect or malfunction was caused by damage thermostat will be set to the temperature programmed for the current which occurred while the product was in the possession of a consumer.
  • Page 3: Fonctionnement

    RTH221 Guide de l’utilisateur Thermostat programmable Bouton-sélecteur du ventilateur  Fonctionnement Utiliser le bouton-sélecteur Fan pour choisir le mode de fonctionnement du ventilateur. Contrôles • Auto : Le ventilateur fonctionne uniquement lorsque le chauffage ou la climatisation est en marche (réglage habituel). Réglage de l’horloge •...
  • Page 4: Remplacement Des Piles

    Pour obtenir de l’aide sur ce produit, veuillez consulter le site ou vous adresser aux Services à la clientèle de Honeywell en composant le 1 800 468-1502. Pour gagner du temps, veuillez prendre en note le numéro de modèle et le numéro de code de date du thermostat avant d’appeler.
  • Page 5: Ajuste Del Reloj

    RTH221 Guía del usuario Termostato programable  Funcionamiento ADVERTENCIA: PELIGRO DE DAÑAR EL EQUIPO No se debe hacer funcionar el sistema de refrigeración cuando la temperatura exterior sea inferior a 10 ºC (50 ºF). Controles Botón selector del ventilador Ajuste del reloj o del horario Utilizar el botón selector Fan para elegir el modo de funcionamiento del Botón selector del ventilador...
  • Page 6: Reemplazo De Las Pilas

    La nueva temperatura se utilizará hasta el principio del período siguiente. Honeywell garantiza por un período de un (1) año, a partir de la fecha de compra por el consu- midor, que este producto, sin incluir las baterías, no presentará defectos en los materiales ni en NOTA: para visualizar la temperatura del punto de ajuste, presionar una vez lo referente a la mano de obra, en condiciones normales de uso y de servicio.
  • Page 7 RTH221...
  • Page 8 RTH221 Printed in USA 08/2011...

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  • marilyn Nov 03, 2015 08:51:
    why when I print a page .Large print covers the answer can,t see what im looking for.