Default Thermostat Settings - Lennox MERIT 51M32 Operation Manual

Default Thermostat Settings

Default Thermostat settings are in table 1.
Default Thermostat Settings
Mode
Setpoint
Fan
Filter Reminder
Equipment Protection
Timers
Technical Specifications
Thermostat Type
Electronic nonprogrammable thermostat for 1H/1C, heat
pump with electric or gas backup heat source, non−power
robbing applications.
Power Supply Range
18VAC − 30VAC (24VAC nominal), 60Hz
Temperature Display
Display Scale: Fahrenheit or Celsius user selectable (via
DIP switches)
Display range: 35°F (2°C) to 99°F (37°C)
Display resolution: 1°F (1°C)
Display Accuracy: +/−1°F
Temperature Measurement Range
Measurement Scale: Fahrenheit
Measurement Range: 35°F to 99°F
Measurement Resolution: 0.5°F
Measurement Accuracy: +/−1°F
Field Offset: via DIP switches to +/−3°F
Sampling Method: temperature measurements sampled
every 15 seconds. Displayed temperature is the average of
the last four measurements.
Temperature Setpoint Range
Setting range: 50°F (10°C) to 90°F (32°C)
Setting resolution: 1°F (1°C)
Fan Control
AUTO or ON modes.
Backup Heat Source Selection
Electric or gas furnace, selectable via DIP switch #5 (Aux or
Dual, respectively). See also Thermostat Output section.
I/O Relays
All thermostat relays are latching type to minimize power
consumption. See table 2.
Table 1
Heat
70°F (or 21°C)
Auto
OFF (reminder setting = 0)
reset back to zero
51M33 Terminal Designations
Connections
O
B
R
G
Y1
W1
L
C
E
T
T
Equipment Protection Timers
Minimum Compressor OFF time: 5 minutes
Minimum Compressor ON time: 4 minutes
Minimum Furnace ON time: 3 minutes
Minimum backup furnace cycle time (elapsed time be-
tween any furnace activation and the next furnace activa-
tion): 6 minutes.
Minimum elapsed time between any compressor activation
and the next compressor activation: 6 minutes.
NOTE − All protection timers (except the compressor OFF
timer) can be over−ridden if a heating or cooling demand is
initiated or terminated using the UP, DOWN, HEAT, or
COOL buttons.
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.
Balance Point
0°F (OFF) to 55°F, user selectable.
Page 6
Table 2
Description
Reversing valve, cool active
Reversing valve, heat active
24VAC
Fan control
First stage cooling/heating, compres-
sor generated
Auxiliary heating, furnace generated
Service Indicator
24VAC common
Emergency heat
Outdoor temperature sensor
connection 1
Outdoor temperature sensor
connection 2