Why Would a New Hot Water Heater Stop Working?

Water Heaters

• Common types of water heaters include natural draft water heaters, power vents, direct vents and high-efficiency condensating water heaters. Natural draft appliances generally utilize a pilot and vents through the chimney. Power-vent and direct-vent water heaters release flue gases through the wall, while high-efficiency condensating units are directly vented, but flue gases are cooled enough to produce condensate and are poured out to a drain.

Common Problems

• One of the most common problems with natural draft water heaters is a defective thermocouple, causing no millivoltage to be sent to the gas valve to keep it open. Power-vent and direct-vent water heaters have sensors that detect the movement of flue gases. If anything is plugging the vent or simply slowing down the movement of flue gases, the unit shuts down to protect the home's occupants. High-efficiency water heaters require condensate to be pumped out to the drain and blockage will signal for the unit to shut down.

Troubleshooting

• For natural draft water heaters, individuals can test the thermocouple by lighting the pilot while holding down the pilot button for 30 seconds. If the flame goes out when the pilot button is released, the thermocouple is not working.

  Check all vents for power-vent and direct-vent water heaters. If it is blocked by snow or debris outside, the water heater will not work. Sometimes the full or partial blockage can be a result of someone putting something in the piping such as stones and dirt or from an animal that may have crawled into the vent, if a proper netting was not installed. Check the drainage line for high-efficiency water heaters. The hose is usually clear and can be disconnect from the units. Pour water into the hose and see if anything comes out the other end. If a pump is used when the drain is too far away, check that it is getting power and that the hoses are attached securely.