Thursday, December 31, 2015

No #HotWater? What to Do When Your #WaterHeater's #PilotLight Goes Out

I should have written this down when the details were fresh in my mind, but Christmas sort of got in the way. In any case, here is some information gained from trial, error, and helpful professionals from variously Googled forums. Hopefully I have paraphrased and synthesized this information as accurately as possible.

Spoiler: I fixed a "broken" water heater ... and you can, too!*

If you no longer have hot water going through your plumbing, one possible cause is that the water heater's pilot light has went out. The pilot light heats up a mostly-copper part called the thermocouple, which "tells" the main gas line into the water heater to provide more gas. When the thermocouple no longer "senses" the pilot light, it basically shuts off the main gas line -- for safety reasons, of course. The solution to this problem can be solved by going through one, two, three, or four steps.

You'll need the following tools (and perhaps more items): Adjustable crescent wrench, hex keys (Allen wrenches) of varying size, Phillips screwdriver, flathead screwdriver, fine sandpaper, a pin or re-shaped paper clip, a spray bottle filled with soapy water, an Xacto knife, HVAC tape, and whatever else I have neglected to list here but mentioned below.

If you're not comfortable with maintaining or repairing a water heater, then please skip all the way to step four, where you pay a licensed professional to essentially try out steps one through three. If your water heater is still under warranty, then perhaps you want to let the manufacturer or seller solve the issue. For the rest of us ...


To check if the water heater's pilot light is lit, remove the first metal "cover" (or equivalent) to reveal a glass window into the water heater. Get down on your knees, and look into the window, looking up and to the left (usually). If the pilot light is nowhere to be seen, then follow the instructions to reignite the pilot light. Typically, you would have to set a dial and another knob to pilot light mode -- read the water heater's specific instructions. For typical early-21st century water heaters, you have to hold down a button, which temporarily provides a small amount of gas into the pilot light chamber, while pressing an igniter button, which creates a spark in the chamber. The pilot light should then start (keep looking into the window, up and to the left). Hold on to the temporary gas button for about a minute. This should allow the pilot light to heat up the thermocouple enough to tell the main gas line to keep it coming.

After about a minute, let go of the temporary gas button. If the pilot light is still on, then set the dials and/or knobs to the mode and temperature level from before. Congratulations, you now have hot water again!

If that doesn't work ...


If the pilot light vanishes, then it might mean that the water heater's thermocouple doesn't sense the pilot light somehow. This might mean that the thermocouple is dirty, the pilot light part is clogged, or one or more parts are damaged/need replacing. Open up your water heater, thus voiding the warranty if that is still relevant, and start cleaning! Well ...

SHUT OFF THE GAS LINE INTO YOUR WATER HEATER FIRST! From the water heater, there should be a gas line that leads to a knob, pointing in a direction. Just turn that knob 90 degrees clockwise to shut off any gas flowing into your water heater. Yes, the thermocouple tells the main gas line to flow or shut, but manually shutting it yourself is a proper safety precaution.

You'll need an adjustable crescent wrench to remove the thermocouple, pilot gas line, and main gas line from the control box (on YouTube, you'll probably find the videos that aided me, as well). Typically, you should easily slide off the igniter button assembly from the control box. You'll probably need a hex wrench or driver to remove the hex screws from the second metal cover (with the window).

When you pull open the second metal cover -- you might need a flathead or something to help pry -- you should be able to see an assembly with the pilot light, the thermocouple, and the igniter. If the thermocouple looks really sooty, then use sandpaper to clean off all that caked-on ash. Just in case, use a thin piece of metal (like a re-shaped paper clip) to clean the inside of the pilot light part, which might have its fair share of dirt.

Close up the second cover (with the window), screw in the screws, and use your wrench to reconnect the main gas line, the pilot light gas line, and the thermocouple. Snap or slide the igniter back into place. Turn on the previously-shut gas line knob (90 degrees counterclockwise this time). Spray the contacts were you reconnected the main gas line and the pilot gas line with soapy water. If it bubbles, then shut off the gas line knob (90 degrees clockwise), tighten the connections with your wrench, and test with soapy water again. Hopefully it doesn't bubble this time. If either gas line continues to bubble, and remains to be a problem after tightening everything, then there's a gas leak -- CALL THE GAS COMPANY NOW!

Assuming that your gas connections are once again tight, then try out the repair. The gas line knob should be in the "on" position. Like in step one so many paragraphs ago, reignite the pilot light. If the pilot light remains lit when you let go of the temporary gas button, then proceed to fully turn on your water heater -- you now have hot water! Congratulations! Cleaning the thermocouple and/or unclogging the pilot light part must have done the trick! The pilot heats up the thermocouple, which tells the gas line to keep it coming, and a big fire will soon ignite to heat up your water.

If that doesn't work ...


Sometimes cleaning a thermocouple isn't enough. The thermocouple probably doesn't work anymore. That's probably why the pilot light disappeared in the first place. The thermocouple stopped working, so it could not sense the pilot light, and in turn, informed the main gas line to shut off, which inevitably extinguished the pilot light (no gas, no constant fire) -- in other words, no more hot water.

Replacing the thermocouple is fairly straightforward and more importantly, very inexpensive. Depending on the length of copper you need, it'll cost maybe $10 to $18 at a brick and mortar hardware store -- probably cheaper online. Anyhow, I'm getting ahead of myself.

Like before, shut off the main gas knob into the water heater. Disconnect the two gas lines, the thermocouple, and the igniter. Unscrew the cover with the window. Remove the cover. Unscrew (with a Phillips screwdriver, usually) the thermocouple-pilot-igniter assembly to remove the thermocouple. Use an Xacto knife to cut the thermocouple from any rubber seal housing; some HVAC tape and pieces of insulation might be necessary to plug in a broken rubber seal.

Measure the size of the thermocouple, and buy a replacement thermocouple that is the same size or a bit longer.

Reassemble the thermocouple-pilot-igniter assembly -- re-screw and reattach as necessary. Pretty much replace lines and wires as they were before, and use some insulation and HVAC tape to fill in any new gaps you've made in the process. Reinstall the cover with the window. Reconnect the gas lines, thermocouple, and igniter. Reopen the gas line by turning the appropriate knob 90 degrees clockwise. Check for gas leaks with soapy water.

Finally, reignite the pilot light. Hopefully it will stay lit, as you set the water heater to fully operational mode. If it works, congratulations! It was the thermocouple all along! Enjoy your hot water! Remember to reinstall the first metal cover, which hides the pilot light window.

If that doesn't work ...


I'm out of ideas at this point. You've spent about $10 on a thermocouple that didn't do the trick, so expect to pay dozens more, if not hundreds of dollars, in further repairs. Think of it this way: It's better to spend $10 before spending a couple hundred more, than it is to spend a couple hundred on a repair that could have cost only $10. If you are comfortable with do-it-yourself repair, then I would advise that you try to fix it, with simpler solutions, before calling a professional.

Before I end this entry, I'd like to thank all the HVAC/plumbing professionals who have basically given away various "trade secrets" relating to water heater repair. They didn't have to, but in the interest of sharing useful information to homeowners, you've saved so much money for so many people. Cheers! This long-winded article is basically written around two useful bits of information:

1. Look up and to the left to see the pilot light, and
2. Replace the thermocouple.

I hope this information is helpful. If any of this text is confusing, please go to YouTube to see various professionals and D.I.Y.-ers basically do these exact repair solutions I've written. Just search for "water heater" and "thermocouple."

In any case, if I don't post again until 2016, I want to wish you a Happy New Year! Cheers!

*Since I am not an HVAC professional or a plumber, this blog post is for entertainment purposes only, so if something useful (or disastrous) happens, then it's not my fault, all right?

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