Maintenance Reminder
Settings of Off, 6 or 12 (months of chronological time) are available. When programmed time has elapsed, a mainte- nance indicator
Service Reminder
The SERVICE indicator is displayed only under the follow- ing conditions:
Sif the thermostat Y1 terminal has been activated with 24VAC for at least 5 minutes, AND the L terminal is shorted to the R terminal;
OR
Sif the thermostat Y1 terminal has been activated with 24VAC for at least 5 minutes, AND the L terminal is shorted to the C terminal.
Power Loss/Recovery
Thermostat memory is retained for a minimum of 24 hours during a power loss (includes retention of program infor- mation, HOLD status, programmed temperature setpoint, heat/cool and fan mode settings, filter reminder status, maintenance reminder status, and equipment protection timers). After 24 hours of power loss, programmed settings will be lost and replaced with default settings.
IMPORTANT
Power must be applied for at least six consecutive hours prior to a power loss in order for memory to be retained for the specified time.
LCD Backlight
Activated for 30 seconds when any button is pressed.
NOTE − During an electrical storm or similar disturbance, the backlight may activate for a few seconds. This is nor- mal and will no longer occur after the electrical disturbance has passed.
Thermostat Operating Conditions
35°F to 105°F, 5% to 90% RH
Thermostat Storage Conditions
−40°F to 185°F, 5% to 95% RH
Thermostat Output Table
Table 5 depicts the 51M34 thermostat output states for var- ious input conditions.
Table 5
Thermostat Outputs
Condition | W1 | Y1 | G |
|
|
|
|
Gas Heat, Auto Fan
HEAT Demand | X |
|
|
|
|
|
|
COOL Demand |
| X | X |
|
|
|
|
No Demand |
|
|
|
|
|
|
|
Gas Heat, Continuous Fan |
|
|
|
|
|
| |
HEAT Demand | X |
| X |
|
|
|
|
COOL Demand |
| X | X |
|
|
|
|
No Demand |
|
| X |
|
|
|
|
Electric Heat, Auto Fan |
|
|
|
|
|
| |
HEAT Demand | X |
| X |
|
|
|
|
COOL Demand |
| X | X |
|
|
|
|
No Demand |
|
|
|
|
|
|
|
Electric Heat, Continuous Fan |
| ||
|
|
| |
HEAT Demand | X |
| X |
|
|
|
|
COOL Demand |
| X | X |
|
|
|
|
No Demand |
|
| X |
|
|
|
|
NOTE − X = output is activated with 24VAC.
Page 8
505048M 5/1/05
