Equipment Protection Override

Both the minimum compressor OFF timer and the mini- mum equipment cycle timer can be over−ridden by press- ing and holding either the HEAT or COOL button down for 4 seconds.

Over−Temperature Protection

Thermal mechanical switch opens W1 at 93°F+/−6°F.

Filter Reminder

Settings of 0 (Off), 1, 3, 6 or 12 months are available. When programmed time has elapsed, a FILTER indicator is dis- played.

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 programmed temperature setpoint, heat/cool and fan mode settings, fil- ter reminder status, and equipment protection timers). Af- ter 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 8 seconds when any key is pressed.

NOTE − During an electrical storm or similar disturbance, the backlight may activate for a few seconds. This is normal 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

The following table depicts the 51M32 thermostat output states for various input conditions. See table 2.

Table 2

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 6

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Image 6
Lennox International Inc 51M32 operation manual Thermostat Output Table