SYSTEM LOCKOUT AND

DIAGNOSTIC FEATURES

SYSTEM LOCKOUT FEATURES

When system lockout occurs, the gas valve is de-energized, the circulator blower is energized at heat speed, and, if flame is sensed, the inducer blower is energized. The diagnostic indica- tor light will flash or glow continuously to indicate system status.

(System lockout will never override the precautionary fea- tures.)

To reset the control after system lockout, do one of the following:

1.Interrupt the call for heat or cool at the thermostat for at least one second but less than 20 seconds (if flame is sensed with the gas valve de-energized, interrupting the call for heat at the thermostat will not reset the control).

2.Interrupt the 24 VAC power at the control for at least one second. You may also need to reset the flame rollout sensor switch.

3.After one hour in lockout, the control will automatically reset itself.

DIAGNOSTIC FEATURES

The 50A65-843 control continuously monitors its own operation and the operation of the system. If a failure occurs, the LED will indicate a failure code as shown below. If the failure is internal to the control, the light will stay on continuously. In this case, the entire control should be replaced, as the control is not field-repairable.

If the sensed failure is in the system (external to the control), the LED will flash in the following flash-pause sequences to indicate failure status (each flash will last approximately 0.25 seconds, and each pause will last approximately 2 seconds).

1 flash, then pause

System lockout

2 flashes, then pause

Pressure switch stuck closed

3 flashes, then pause

Pressure switch stuck open

4 flashes, then pause

Open limit switch

5 flashes, then pause

Open rollout switch

6 flashes, then pause

115 Volt AC power reversed/Im-

 

proper ground

7 flashes, then pause

Low flame sense signal

8 flashes, then pause

Check ignitor

Continuous flashing

Flame has been sensed when

(no pause)

no flame should be present (no

 

call for heat)

The LED will also flash once at power-up.

7

Page 6 Page 8
Page 7
Image 7
White Rodgers 50A65-843 installation instructions System Lockout Diagnostic Features, System Lockout Features
Page 6 Page 8

50A65-843 specifications

The White Rodgers 50A65-843 is a sophisticated and reliable universal gas valve designed for gas-fired heating systems. It is widely praised for its versatility and performance across a variety of residential and commercial applications. One of its main features is its ability to accommodate both natural gas and propane, allowing homeowners and installers flexibility in fuel choice. The 50A65-843 also supports various types of heating systems, including furnaces, boilers, and other gas appliances.

A key technological highlight of the White Rodgers 50A65-843 is its microprocessor-based control. This advanced technology enables precise regulation of gas flow and enhanced ignition control, ensuring optimal efficiency and safety in operation. The valve is equipped with an integrated flame sensing system, which continuously monitors the flame presence and adjusts gas flow accordingly. This not only improves the unit's reliability but also contributes to energy savings and reduced emissions.

The valve is designed with user-friendly features that simplify installation and maintenance. The standardized dimensions and connection configurations make it compatible with a wide range of existing systems, reducing the need for extensive retrofitting. Additionally, color-coded wiring and clear labeling facilitate quick and easy electrical connections, making it an ideal choice for HVAC technicians.

The 50A65-843 also boasts a high level of durability and robustness. It is built with premium materials that can withstand harsh operating conditions, ensuring a long service life. The unit has been rigorously tested for performance and reliability, meeting or exceeding industry standards.

Moreover, the White Rodgers 50A65-843 includes safety features such as a redundant safety shut-off. This feature is critical in preventing gas leaks and ensuring user safety by shutting off gas flow in the event of a malfunction.

In summary, the White Rodgers 50A65-843 gas valve is a versatile and highly efficient component that is easy to install and maintain. Its advanced control technologies, safety features, and robust construction make it a preferred choice for both professionals and homeowners looking for reliable heating solutions. With its proven performance and adaptability, the 50A65-843 continues to set a high standard in the HVAC industry.
Top Page Image Contents