WIRING

TYPICAL SYSTEM WIRING TABLE

50A66

TERMINAL

SYSTEM COMPONENT

TERMINAL

 

TYPE

 

CONNECTION

W

 

 

 

 

low voltage thermostat W terminal (or equivalent)

G

Terminal

 

low voltage thermostat G terminal (or equivalent)

R

block with

 

low voltage thermostat R terminal (or equivalent)

Y

captive

 

low voltage thermostat Y terminal (or equivalent)

 

screws

 

 

(2nd wire from Y terminal goes to 24 VAC HOT side of

 

 

 

 

 

compressor contactor coil)

C

 

 

 

 

24 VAC COMMON side of compressor contactor coil

HLO (Pin 1)

 

 

 

 

high limit OUTPUT

Not Used (Pin 2)

 

 

 

 

 

TH (Pin 3)

 

 

 

 

24 VAC transformer (low voltage HIGH side)

Not Used (Pin 4)

HLO

PSO

HLI

PSI

 

RO1 (Pin 5)

rollout switch OUTPUT

 

 

 

 

TR (Pin 6)

MV

RO

GND

RO

24 VAC transformer (low voltage COMMON side)

LO

OUT

OUT

 

 

 

 

HLI (Pin 7)

TH

TR

COM

MV

high limit INPUT

 

 

 

MV

 

 

GND (Pin 8)

 

 

 

 

MUST BE RELIABLY GROUNDED TO CHASSIS

MV COM (Pin 9)

 

 

 

 

gas valve COMMON

PSI (Pin 10)

 

 

 

 

pressure switch INPUT

RO2 (Pin 11)

 

 

 

 

rollout switch INPUT

MV (Pin 12)

 

 

 

 

gas valve

IND

 

 

 

 

inducer HOT side

IGN

IND

IGN

IND

IGN

ignitor HOT side

IND N

N

N

 

 

 

inducer NEUTRAL side

 

 

 

 

IGN N

 

 

 

 

ignitor NEUTRAL side

COOL

1/4” spade terminal

circulator blower COOL SPEED terminal

HEAT

1/4” spade terminal

circulator blower HEAT SPEED terminal

PARK (3 terminals)

1/4” spade terminal

unused circulator blower terminals

LINE

1/4” spade terminal

input voltage (120 VAC) HOT side

XFMR

1/4” spade terminal

24 VAC transformer line voltage HOT side

EAC (optional)

1/4” spade terminal

electronic air cleaner HOT side

HUM (optional)

1/4” spade terminal

humidifier HOT side

120 VOLT NEUTRAL

1/4” spade terminal

Terminals for 120 Volt NEUTRAL for line, transformer,

(5 terminals)

 

 

 

 

circulator, electronic air cleaner and humidifier

FP (E33)

3/16” spade terminal

flame sensor probe*

FAN

1/4” spade terminal

Circulator blower fan speed terminal

24 V HUM (E2)

1/4” receptacle

 

24 VAC humidifier

* maximum recommended flame probe wire length is 36 inches.

5

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White Rodgers 50A66-743 installation instructions System Component, Terminal, Connection, Typical System Wiring Table

50A66-743 specifications

The White Rodgers 50A66-743 is a state-of-the-art heating and cooling thermostat designed for maximum comfort and efficiency in residential environments. This versatile device is known for its reliability and user-friendly features, making it a popular choice among homeowners and HVAC professionals alike.

One of the key features of the 50A66-743 thermostat is its programmable functionality. Users can easily set temperature schedules for different times of the day, ensuring optimal energy consumption while maintaining a comfortable home environment. With the option to program up to four different time periods per day, this thermostat allows for customizable comfort tailored to the homeowner's lifestyle.

The 50A66-743 employs advanced technology to facilitate precise temperature control. Its microprocessor-based design ensures accurate readings and smooth operation, allowing the system to maintain the set temperature with minimal fluctuation. This not only enhances comfort but also promotes energy efficiency, which can result in reduced utility bills.

Another notable characteristic of the White Rodgers 50A66-743 is its compatibility with various heating and cooling systems. It can easily integrate with single-stage and multi-stage systems, including gas, oil, and electric furnaces, as well as heat pumps. This versatility makes it an ideal choice for diverse HVAC applications.

User convenience is a top priority with this model, and it is equipped with a clear, easily readable display that provides real-time temperature readings. The backlit screen enhances visibility, making it easy for users to check the status of their heating or cooling systems, even in low-light conditions.

Additionally, the 50A66-743 features a simple interface with intuitive buttons that allow for quick adjustments to temperature settings. This straightforward design minimizes the learning curve for new users, making it accessible for families of all ages.

The thermostat also includes a filter change reminder, which helps homeowners stay on top of maintenance tasks, ensuring optimal system performance. Regular filter changes are crucial for maintaining air quality and efficiency, and this alert serves as a helpful nudge to keep homeowners proactive about their HVAC systems.

In summary, the White Rodgers 50A66-743 thermostat combines advanced technology, user-friendly features, and compatibility with various HVAC systems, making it an excellent choice for those seeking comfort and efficiency in their homes. Its programmable functionality, precise temperature control, and convenient design ensure that users can easily manage their home’s climate while saving on energy costs.