Build one record of the nighttime pattern
Note when the leak begins, the thermostat setting, whether the system was running or had just stopped, and where water first appears. Photograph the water path from a safe location and record the hum without removing covers.
Gather previous invoices and list what was cleaned, repaired, or replaced. Include whether the leak returned the same night or after several days. Describe the hum separately: indoor or outdoor, continuous or intermittent, and only during cooling or also with the fan.
Carrier identifies drainage problems, pan damage, and melting ice as potential water-leak causes. These possibilities need to be checked against the actual pattern. Carrier water-leak guidance.
Ask the provider to explain both findings
The technician should trace where water escapes and assess the component making the hum. The two symptoms may share a cause or may be separate problems. Sound alone cannot establish that a motor, pump, or refrigerant component needs replacement.
Ask for the condition of the drain route and pan, any evidence of icing, and the operating observations supporting the noise diagnosis. Have the provider explain why prior work did not resolve the complaint.
A short visit during the day may miss the circumstances that matter. Ask whether the provider can observe an appropriate run, review recordings, or use approved monitoring to capture the fault without asking you to keep operating a leaking system.
Define what counts as resolved
Before approving more work, request the specific finding, proposed correction, cost, and method of verification. The follow-up should address the original nighttime leak and hum, rather than simply show that the drain accepts water once.
If repeated visits produce changing explanations without evidence, ask a service manager to review the history or obtain an independent diagnosis.
Send one timeline, safe photos, sound recording, and prior invoices with your request. Keep cooling off while the leak remains unresolved, and use another cooled location if the home becomes too hot.