What is the purpose of testing CO on water heaters?

Testing carbon monoxide (CO) levels on water heaters is primarily aimed at assessing combustion efficiency and safety. When a water heater operates, it burns fuel to produce heat for heating water. If there is improper combustion—whether due to insufficient air supply, incorrect venting, or malfunctioning parts—it can lead to the production of CO, a dangerous gas that can be harmful or even fatal at elevated levels.

By measuring CO emissions, technicians can identify whether the heater is functioning properly and safely. High CO levels may indicate that the appliance is not operating efficiently, which can reduce its lifespan and increase the risk of carbon monoxide poisoning. Ensuring low CO emissions helps to confirm that the water heater is not only efficient in its energy use but also poses no health risks to individuals nearby. This is vital for maintaining a safe residential environment.

The other options are focused on different aspects that do not directly relate to the specific purpose of monitoring CO levels in water heaters. Proper air flow in heating systems, installation costs, and measuring water temperature all contribute to the overall efficiency and functionality of the system but do not specifically address the critical safety concerns associated with CO emissions.