Q: I jumped in my shower this morning and, holy cow, was it cold! After a quick inspection, I discovered my water heater's pilot light out. Should I try to relight it?
A: That depends on why the light blew out. The issue may have been something as simple as a draft, a dirty pilot orifice, or a worn-out part-or the extinguished pilot light could be a sign of something more troublesome. First, sniff out the potentially larger problem: Do you smell gas? If you do, leave your house and call the gas company! Otherwise, keep reading to determine how you can fix the problem by yourself. (Note: Unfortunately, if your water heater has an enclosed burner chamber, you're probably out of luck as far as a DIY fix; only a professional plumber should access an enclosed burner chamber.)
When you see your pilot light out, you can usually relight it. A downdraft in a vent pipe on a windy day or even the breeze through an open window can be enough to snuff out a pilot light. Relighting instructions are similar for most water heaters, and you can find them permanently affixed to the side of your unit.
In order to relight the pilot, remove the access cover at the bottom of the water heater. Both the control knob and the water temperature knob should be in the “Pilot” position. While depressing the control knob, light the pilot light with a long match or wand lighter. Once the pilot ignites, continue holding the knob down for a full minute to bleed air out of the line. (For a water heater with an automatic igniter, the relighting process is virtually the same. Instead of using a lighter or match, though, you'll push the striker knob repeatedly while depressing the control knob until the pilot ignites.)
Relighting the pilot light may or may not be all you need to do to start up your water heater once more. Depending on what happens after the pilot ignites, proceed with one of the following:
• If the flame remains lit, you're good to go! Simply replace the cover plate, turn the control knob to “On,” and select the desired temperature on the water temperature knob so that you can return to a refreshing hot shower.
• If the pilot light flickers and goes out soon after relighting, clean the pilot orifice. A dirty pilot light orifice hinders gas flow, but the fix is simple. First, shut off the gas to the water heater (look for a valve on the gas line that supplies the unit). Remove the pilot orifice fitting, which is located under the access cover, by twisting it to the left. Then, unscrew the orifice itself from the fitting. Once the fitting has been disassembled, clean all surfaces with a cotton swab dampened with rubbing alcohol. After reassembling and reattaching the fitting, relight the pilot light as described above.
• If you're able to light the pilot light, but it goes out when you release the control knob, the thermocouple probably needs replacing. The thermocouple is a safety device that shuts off gas flow if it senses the pilot light is out, but when damaged it loses its regulatory ability. This fix is a bit more complicated than the first two, but a replacement is inexpensive-often less than $20.
This piece, which resembles a copper tube, connects the control panel to the burner assembly, which is located behind the access panel. Before attempting to disassemble anything, shut off the gas to the water heater. Next, release the burner assembly by using an adjustable wrench to detach the thermocouple tube, the pilot light tube, and the gas supply tube from the control panel-the burner assembly should slide right out. (Hint: Because there are various sizes and types of thermocouples, the best way to get an exact match is to take the damaged thermocouple with you when buying a replacement.) After replacing the damaged thermocouple with the new one, slide the burner assembly back into place, reattach the tubes, and then relight the pilot light as described above.