Final answer:
A low water cut-off device can be installed to protect a hot water boiler from low water level. This device shuts off the burner or heating elements when the water level drops below a safe level, preventing damage from overheating.
Step-by-step explanation:
To protect a hot water boiler from low water level, a low water cut-off device can be installed. This device is designed to monitor the water level in the boiler and shut off the burner or heating elements if the water level drops below a safe level. When the water level drops, the low water cut-off sends a signal to shut down the boiler, preventing damage from overheating and potential hazards.
Unlike other options mentioned in the question, such as a pressure relief valve, flow switch, or expansion tank, the low water cut-off is specifically designed to address the issue of low water level and protect the boiler.
For example, if there is a leak in the system or a problem with the water supply, the low water cut-off will detect the low water level and automatically shut down the boiler, preventing further damage. This device is essential for maintaining the safety and efficiency of a hot water boiler.
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