Thermostat Output Table - Lennox MERIT 51M32 Operation Manual

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:
S
if 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
S
if the thermostat Y1 terminal has been activated
with 24VAC for at least 5 minutes, AND the L
terminal is shorted to the C terminal.

Thermostat Output Table

The following table depicts the 51M32 thermostat output states for various input conditions. See table 2.
Condition
Gas Heat, Auto Fan
heat demand
cool demand
no demand
Gas Heat, Continuous Fan
heat demand
cool demand
no demand
Electric Heat, Auto Fan
heat demand
cool demand
no demand
Electric Heat, Continuous Fan
heat demand
cool demand
no demand
NOTE −
X = output is activated with 24VAC.
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.
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
Table 2
Thermostat Outputs
W1
X
X
X
X
Page 6
IMPORTANT
Y1
X
X
X
X
G
X
X
X
X
X
X
X
X
X