Lennox International Inc. MERIT 51M32 - Manual (Page 6)

Page 6
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.
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.