What action should be taken if the condensate drain is blocked?

When a condensate drain is blocked, the appropriate action is to clear the blockage and check for further issues. This is important because a blocked condensate drain can lead to water buildup, which can cause various problems such as water leaks, improper functioning of the system, and even damage to the surrounding structure or equipment.

Clearing the blockage ensures that the condensate can flow freely, allowing the system to operate efficiently. After addressing the immediate issue, it's also crucial to check for further problems that might have caused the blockage or may arise due to the blockage, such as mold development or corrosion, which could lead to more complex or costly repairs if not addressed promptly.

Taking preventive steps helps maintain the system's longevity and reliability. The other options do not address the underlying mechanical issue and could lead to further complications and service disruptions.