RTH221 PROGRAMMABLE THERMOSTAT
Wake
Morning temperature
Leave
Daytime temperature
Return
Evening temperature
Sleep
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.
2.2 Factory settings
Period
Start time
Wake
6:00 a.m.
Leave
8:00 a.m.
Return
6:00 p.m.
Sleep
10:00 p.m.
2.3 Modifying the schedule
1. Press the Set button twice until the
message Set Schedule appears.
The start time of the first period
(Wake) will flash.
2. Press the or button to set the
time.
3. Press the Set button. The tempera-
ture setting for that period will flash.
4. To program the temperature
settings for the cooling mode, place
the System switch in Cool. To
program the temperature settings for the heating
mode, place the switch in Heat.
5. Press the or button to set the temperature.
6. Press the Set button. The start time of the next
period will flash.
NOTE: To skip a period, press the Hold button for four
seconds while that period is displayed. When a
period is skipped, dashes appear instead of the
time and temperature display for the period. Only
the Wake period cannot be skipped.
7. Repeat steps 2 through 6 for each of the remaining
periods.
8. Once all adjustments are made, press the Run but-
ton to save them and exit. (The changes are also
saved if you do not press any button for 60 seconds.)
2.4 Temporary override of schedule
To temporarily ignore the programmed schedule, press
or until the desired temperature is displayed. The word
Temporary will appear on the screen and the period
display will flash to indicate that the current period has
been overridden. The new temperature will be used until
the next period begins.
69-2062EFS—03
Heat
Cool
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)
NOTE: Pressing or once will display the setpoint
temperature. To change the setpoint temperature,
press either button more than once.
Press the Run button if you wish to cancel the temporary
setting before the beginning of the next period.
2.5 Permanent override of schedule
To permanently ignore the programmed schedule, press
or until the desired temperature is displayed. Then,
press the Hold button to maintain the new temperature
indefinitely. The word Hold will appear on the screen.
Press the Run button if you wish to cancel the override
and resume the programmed schedule. The word Hold will
disappear and the thermostat will be set to the
temperature programmed for the current period.
3. BATTERY REPLACEMENT
Set the System switch to Off before removing the
batteries. Otherwise, the heating/cooling system could
remain activated even when batteries are removed.
Install two fresh AAA batteries when Lo Batt (low
batteries) flashes on the screen. The icon appears for 60
days before the batteries are depleted. Replace batteries
once a year, or when you will be away for more than a
month.
Most settings are stored in non-volatile (permanent)
memory. Only the clock must be set if the thermostat was
without batteries.
4. IN CASE OF DIFFICULTY
Screen is blank.
Ensure two fresh AAA alkaline batteries are correctly
installed.
Temperature settings cannot be changed.
• The System switch is off.
• You are setting the temperatures outside their
allowable ranges:
—
Heat: 40 °F to 90 °F (4.5 °C to 32 °C).
—
Cool: 50 °F to 99 °F (10 °C to 37 °C).
Cool On is flashing.
The compressor protection delay has been activated.
Cooling will not be activated until the delay ends (maxi-
mum of five minutes).
HI appears on the screen.
The ambient (measured) temperature is above 122 °F (50
°C).
LO appears on the screen.
The ambient (measured) temperature is below 32 °F (0
°C).
E1 appears on the screen.
The temperature sensor circuit is opened. Replace the
thermostat.
E2 appears on the screen.
The temperature sensor circuit is shorted. Replace the
thermostat.
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