Lennox SignatureS
tat 81M26 User Manual

SignatureStat t Thermostat
Page 23
81M272 Stage Heat & Cool, Non−Heat Pump
Table 4. 81M27 LED Indicators
COOL Cooling mode (Y is active)
CHECK 24V signal is present on the L" terminal
HEAT Heating mode (W1 is active)
Table 5. 81M27 Terminal Designations
R 24 Vac power input from HVAC system
C 24 Vac common
Y1 Energized on call for 1st stage COOL
Y2 Energized on call for 2nd stage COOL
E/W1 Energized on for 1st stage HEAT
W2 Energized on for 2nd stage HEAT
G Energized on call for FAN
H Energized on a call for humidification
D De−energized on a call for dehumidification (reverse logic)
O COOL active (always energized when the stat is in COOL mode,
default value is OFF)
B HEAT active (always energized when the stat is in HEAT mode,
default value is ON)
L Illuminates CHECK LED when energized with 24VAC
NOTE − High−temperature PEPI disables W1 ands W2 when ambient tem-
perature exceeds 95F.
Fan AutoIn COOLING, the indoor blower cycles with calls for cooling.
In HEAT, and with the thermostat set for gas/oil, the indoor blower (G) does
not cycle with a call for heat. The independent fan control in the flue will
cycle the indoor blower as necessary.
GO TO: MENU > INSTALLER SETTINGS > SYSTEM SETUP > GAS/OIL
When in electric heat, the indoor blower (G) cycles with the call for heat.
GO TO: MENU > INSTALLER SETTINGS > SYSTEM SETUP > ELECTRIC
Fan ONThe indoor blower is ON continuously regardless of whether
the heating or cooling equipment is running.
Thermostat Off" ModeIn this mode, the heating and cooling and
H/D terminals are inactive. The O or B terminal is active. This is determined
by the last state of O/B. For example, if the mode goes from heat (B active)
to off, then B will be active in the off mode. Default on power−up is B active.
The G terminal may be active if FAN ON is selected from the menu.
81M282 Stage Heat & Cool Heat Pump
Table 6. 81M28 LED Indicators
AUX W2 is active.
CHECK 24V signal is present on the L" terminal
EMER Emergency heat is enabled in menu.
Table 7. 81M28 Terminal Designations
R 24 Vac power input from HVAC system
C 24 Vac common
Y1 Energized on for 1st stage HEAT or COOL (heat pump com-
pressor control)
Y2 Energized on call for 2nd stage COOL
E/W1* Energized on call for emergency heat
W2* Energized on for 2nd stage HEAT
G Energized on call for FAN
H Energized on a call for humidification
D De−energized on a call for dehumidification (reverse logic)
O COOL active (always energized when the stat is in COOL
mode, default value is OFF)
B HEAT active (always energized when the stat is in HEAT
mode, default value is ON)
L Illuminates CHECK LED when energized with 24VAC
* Factory-installed jumper between E/W1 and W2.

Lennox SignatureS
tat 81M26 Specifications

General

Brand	Lennox
Model	SignatureS tat 81M26
Category	Thermostat
Language	English