REPLACEMENT

DEFROST CONTROL BOARD

 

 

 

PRESSURE

 

 

 

 

 

 

SWITCH

 

 

 

 

 

SAFETY CIRCUIT

 

 

 

 

 

CONNECTIONS

 

 

 

 

 

 

 

 

 

/

DIAGNOSTIC LEDs

 

 

 

 

 

 

CONNECTION

FOR

 

 

 

 

 

ONE OPTIONAL

SWITCH

 

 

 

DEFROST

INTERVAL

 

 

 

 

 

 

PS2

 

 

 

TIMING

PINS

 

 

 

 

 

 

 

PS1

 

 

 

 

 

 

 

 

 

 

24V TERMINAL

STRIP

CONNECTIONS

FOR

 

 

 

 

 

TWO OPTIONAL

 

 

 

CONNECTIONS

SWITCHES

 

SERVICE

LIGHT

 

 

[]

ps2

.......

ONNECT,ON

 

 

 

 

 

 

 

 

Psi

.........................

.........................

 

 

 

 

FIGURE 1

 

 

 

Time-Delay

The timed-off delay is five minutes long. The delay feature is provided to help protect the compressor in case of an interruption in power to the unit or when a pressure switch resets.

Pressure Switch Safety Circuit

The defrost control incorporates a pressure switch safety circuit that allows the application of up to two optional pressure switches; high pressure and/or loss

of charge. See figure 1. During a demand cycle, the defrost control will lock out the unit on the third

instance that the unit goes off on any pressure switch wired to this circuit. The diagnostic LEDs will display a pattern for a lockout pressure switch on the third

open pressure switch occurrence. See table 1. The unit will remain locked out until the switch is reset.

Remove factory-installed jumper before connecting optional pressure switches to control board. When two pressure switches are used, wire each switch to one set of terminals PS1 and PS2 on the defrost

control board. See figure 1. When only one pressure switch is used, wire the switch to the two outside terminals of the pressure switch connections.

NOTE: If not using a pressure switch, the

factory-installed jumper wire must be connected.

Diagnostic LEDs

The defrost board uses two LEDs for diagnostics. The LEDs flash a specific sequence according to the condition.

TABLE 1

 

 

DEFROST CONTROL BOARD DIAGNOSTIC LED

 

 

MODE

 

LED 1

LED 2

Normal

Operation/

Flash together

Flash together

Power

to board

 

with LED 2

with LED 1

_me

Delay

 

Alternating

Alternating

 

Flashes

Flashes

To Protect Compressor

 

 

 

 

with LED 2

with LED 1

Pressure

Switch

Open

Off

On

Pressure

Switch

Lockout

On

Off

Board

Malfunction

 

On

On

Page 2

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Lennox International Inc 11K71 installation instructions Time-Delay, Pressure Switch Safety Circuit
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11K71 specifications

Lennox International Inc. is renowned for its innovation and excellence in the heating, ventilation, and air conditioning (HVAC) industry. One of the standout products in its range is the Lennox 11K71, a high-efficiency heat pump that showcases the company's commitment to energy savings, environmental sustainability, and advanced technology.

The Lennox 11K71 is designed for both residential and commercial applications, offering superior performance and reliability. A key feature of this unit is its SEER (Seasonal Energy Efficiency Ratio) rating, which often exceeds 16. This high rating demonstrates the unit’s ability to efficiently cool spaces, making it an ideal choice for consumers looking to reduce their energy consumption and lower utility bills.

One of the main technologies integrated into the Lennox 11K71 is variable speed compression. This allows the unit to adjust its cooling capacity based on the current demands of the environment, leading to enhanced comfort levels and further energy savings. The unit operates at lower speeds for longer periods, dramatically reducing energy consumption while maintaining a consistent temperature.

Additionally, the Lennox 11K71 features a smart thermostat compatibility option, allowing users to connect the system to their smart home networks. This connectivity facilitates remote monitoring and control through mobile devices, providing convenience for users while optimizing energy use.

Another significant characteristic of the Lennox 11K71 is its whisper-quiet operation. The design incorporates advanced sound dampening technology, ensuring that the unit operates quietly, a feature particularly beneficial for residential locations. This emphasis on noise reduction makes the system suitable for multi-family units or homes in noise-sensitive areas.

Durability is also a hallmark of the Lennox 11K71. Constructed with high-quality materials, the unit is built to withstand various weather conditions, ensuring longevity and reliable service. Its streamlined design not only enhances aesthetics but also promotes efficient airflow, further improving the unit's overall performance.

In conclusion, the Lennox 11K71 exemplifies state-of-the-art HVAC technology with its high efficiency, variable speed compression, smart thermostat integration, quiet operation, and robust construction. This heat pump is an excellent investment for anyone seeking an effective and reliable heating and cooling solution. With a focus on energy efficiency and user convenience, the Lennox 11K71 stands out as a leading option in modern HVAC systems.
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