Narrative:

While in cruise the aft flight attendants called the flight deck to report a possible faint electrical smell coming from the aft airplane left lavatory. All cockpit indications were normal. The non-flying pilot reviewed the QRH to look for an applicable procedure. The non-flying pilot reviewed the maintenance logbook for previous related write ups and found none. The non-flying pilot made frequent checks with the aft flight attendants every couple minutes to determine if the smell was getting stronger or dissipating and the flight attendants advised everything was the same; the faint smell was not improving or worsening. During the descent; the flight attendants called to report there was visible smoke coming from under the lavatory sink and they had switched off the water heater. Immediately; the non-flying pilot applied the smoke/fumes/avncs smoke procedure; leading the pilots to turn off the comm push button to deactivate the power to the lavatory and galleys; [and] continued to check with the aft flight attendants on the status of the smoke. They advised the smoke was not getting any worse. We continued to landing. At the gate; maintenance determined the water heater to be faulty and placed the item on MEL. This was a faulty piece of equipment.

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Original NASA ASRS Text

Title: Air carrier flight crew reported smoke and fumes from the aft lavatory due to a faulty water heater.

Narrative: While in cruise the aft flight attendants called the flight deck to report a possible faint electrical smell coming from the aft airplane left lavatory. All cockpit indications were normal. The non-flying pilot reviewed the QRH to look for an applicable procedure. The non-flying pilot reviewed the maintenance logbook for previous related write ups and found none. The non-flying pilot made frequent checks with the aft flight attendants every couple minutes to determine if the smell was getting stronger or dissipating and the flight attendants advised everything was the same; the faint smell was not improving or worsening. During the descent; the flight attendants called to report there was visible smoke coming from under the lavatory sink and they had switched off the water heater. Immediately; the non-flying pilot applied the SMOKE/FUMES/AVNCS Smoke Procedure; leading the pilots to turn off the COMM push button to deactivate the power to the lavatory and galleys; [and] continued to check with the aft flight attendants on the status of the smoke. They advised the smoke was not getting any worse. We continued to landing. At the gate; Maintenance determined the water heater to be faulty and placed the item on MEL. This was a faulty piece of equipment.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.