Massachusetts Oil Burner License Practice Test

If a stack relay fails, what must be done?

1. Adjust its sensitivity

2. Replace it with an approved type controller

3. Disconnect it from the system

4. Recalibrate the existing relay

The correct answer is: Replace it with an approved type controller

When a stack relay fails, replacing it with an approved type controller is essential to ensure safe operation. The stack relay plays a crucial role in monitoring the flue gas temperature and is designed to shut down the burner if temperatures exceed safe limits. If this component is not functioning correctly, the risk of unsafe operation increases significantly, potentially leading to dangerous conditions such as overheating or even a fire. By replacing it with an approved type controller, not only is the safety of the heating system restored, but compliance with regulatory standards is also maintained. Using a device that is specifically approved ensures that the new controller meets safety and operational expectations. Adjusting its sensitivity, disconnecting it from the system, or recalibrating the existing relay may seem like options to address a failure, but they do not resolve the underlying issue of a malfunctioning safety device. Properly functioning safety equipment is critical in oil burner operations, making the replacement the only suitable course of action in the event of a failure.