What is most likely to cause a problem with a chlorinator if the chlorine supply indicator shows no supply?

The correct answer indicates that the most significant issue likely causing a problem with the chlorinator is a clogged injector. The injector plays a critical role in the chlorination process as it draws chlorine from the cylinder and mixes it with wastewater. When this injector becomes clogged, it can prevent chlorine from being effectively introduced into the water system, which would typically result in no chlorine supply being detectable in the indicator.

Understanding that the injector's primary function is to facilitate chlorine mixing with the water highlights why its clogging is a severe issue. If the injector cannot operate correctly, the system indicates low or no flow of chlorine, leading to under-chlorination and potential water quality issues.

While other options may seem plausible scenarios for a lack of chlorine supply, they are not as directly impactful on the operation of the chlorinator as a clogged injector. The cylinder valve being closed would prevent any chlorine flow, but the indicator would show that there is zero supply; the ejector water supply being off might still indicate some chlorine, and a dropped ball in the indicator tube alone does not specifically imply a problem with the chlorinator's functioning beyond simply indicating flow status. Hence, recognizing the role and importance of the injector in this system is crucial for understanding why its clogging poses the