How to Change Thermocouple in Hot Water Heater

Ever got in the shower one morning only to find that you don’t have any hot water?  This recently happened to us – here’s a story of how about 30 minutes of research on the internet saved me ~$500+!

How to Change Thermocouple in Hot Water Heater – Money Saving Breakdown

• Difficulty (Super Easy/Easy/Medium/Hard/Expert): Medium
• Average Savings per Year ($/year): 116
• Time Required (mins): 80
• Savings for your time ($/hr): 87

*Note: I based the savings on having a hot water heater problem every five years.

How to Change Thermocouple in Hot Water Heater – The Background Story

We woke up one morning about two weeks before I’m writing this article.  I jumped in the shower and noticed that the water seemed a little less warm than normal.  I didn’t really think much of it.  Well, my wife had the second shower, and she noticed it in a big way!  The water was barely above room temperature.

So, I went to the garage to check out the water heater.  For some reason the pilot light was out.  “That’s funny,” I thought.  I read through the instructions on the front of the water heater to re-light the pilot without much issue.  It figured it was just some strange fluke…

Well, the next weekend the same thing happened!  I figured maybe the pilot blew out because we left the garage door open for a couple of hours in the afternoon.  My wife threatened calling a plumber to come fix the problem – there’s nothing like threatening to spend a bunch of money to get my attention!

I did a little research on “your hot water heater not working”, and I determined that there were two issues that were the most likely.  Either the pilot light was blowing out due to air flow or the thermocouple was going bad.  Because the house is ~9 years old, the most likely failure mechanism was a bad thermocouple!

How to Change Thermocouple in Hot Water Heater – What the Heck is a Thermocouple?

Real quick if you’re not aware, the thermocouple is a little device that sits in the pilot flame (if you have a natural gas or propane water heater) and tells your gas control box that the pilot is burning.  When it heats up from the pilot light, it sends a small electrical signal to the gas control box to keep feeding a small stream of natural gas to the pilot.  This device ensures that if the pilot light goes out, you don’t fill your garage or house with natural gas and end up killing yourself!  A pretty important device if you ask me 🙂

How to Change Thermocouple in Hot Water Heater – Don’t Ignore the Problem!

Well, for whatever reason, I deluded myself into thinking that the wind probably blew the pilot out.  This worked for about 10 days 🙁  Just this past Thursday, my wife went to give our kids a shower at night and there was no hot water.  “No problem,” I thought.  “That damn pilot must have blown out again.”  I went to the garage to relight it, but it wouldn’t stay lit!  I tried about six times, but it wouldn’t stay.

Shit!  No more hot water for us.  It was about 7:45pm at night, and having a 24-hour plumber come out would cost us nearly $600!!   Why the hell had I put this off?  Could I fix this myself, get it done the same night, and save $600?!?  I was up for the challenge 🙂

How to Change Thermocouple in Hot Water Heater – How Hard Was It?

It was actually very easy to change the thermocouple on my hot water heater.  It was 7:45pm at night, so I zipped over to Home Depot quickly.  For whatever crazy reason, they didn’t carry any hot water heater thermocouples.  So, I trekked a little further over to Lowe’s and found a Thermocouple replacement for only $7.84.  It’s similar to something like this: Water Heater Thermocouple.

It took me about a total of one hour to get the part and get back home.  It only took about ten minutes to change the thermocouple on my hot water heater once I got started.

The moment of truth – I lit the pilot, held the pilot light switch on the gas control box for about one minute, and let up on it.  It stayed lit!!!!  I fixed our hot water heater quickly and saved over $600!!!

How to Change Thermocouple in Hot Water Heater – YouTube Video

I also took an extra ten minutes to make a YouTube video of how to change the thermocouple on your water heater to help other folks out if they run into similar problems.  Here it is below:

How to Change Thermocouple in Hot Water Heater – Final Thoughts

So, what did I learn from all of this?  Well, a couple of things.  First, if you’ve got a potential maintenance issue, don’t put them off.  It will almost always cost you more and cause additional pain if you sit on the issue vs. taking action quickly.  Second, with YouTube and the internet, you can learn to do almost anything yourself!  Unless you’re time constrained, you can almost always get it done the proper way yourself and save a ton of cash!  So if your hot water heater ever has an issue, remember that you can learn how to change the thermocouple in your hot water heater yourself and save $600+!