Checking an electric water heater for leaks

Sept. 1, 2011
Dave Yates' series of steps for checking electric water heater for leaks

Last month's column dealt with a staged set-up utilizing a leaking electric water heater. At our morning shop-meeting, I asked employees, "How would you trouble-shoot that service call?" Imagine how horrified you would be to discover any of your employees acting as did the plumbers in the Hansen "Dateline" segment. I wanted to be sure that everyone knew the proper procedure to follow a logical step-by-step investigation.

Checking an electric water heater for leaks: unless the tank itself has a large enough pin-hole to create a clearly audible "here-I-am" under the jacket, you need to poke and probe for the answer. It's a straight-forward logical series of steps. Since gravity is in play, you start at the top where Hansen's show set up the leak.

1. Top of the tank: Is the top of the tank's jacket wet? Look up! Piping above the water heater can leak, valve packing gland dripping, or an intermittent drain-line leak can make it appear that the water heater is the source. Pretty obvious things, except the drain line leak, which took a few minutes to determine as the root cause of water leaking out of the water heater's base. If the installer had utilized primer, the PVC joint would not have leaked! Flush the toilet, run water at the vanity, or take a shower, and water would steadily drip onto the overhead hot-water line. Gravity and capillary attraction ensured black- and gray-water were compelled by gravity to follow the water-line down to the tank, seep past the hot outlet, saturate the insulation, and puddle onto the floor.

2. Inlet/outlet connections: Over the years, we've seen models with/without heat-traps that required either male or female adaptors. If the tank has factory-installed nipples, then there's a doubled set of threads to check. A leak discovered here doesn't necessarily mean there aren't any others to find and missing more leaks means an expensive callback will rear its ugly head and damage your credibility.

3. Anode rod: Older models will also have a ¾-in." plug in the top of the tank from which an anode rod is suspended in the tank, typically under a plastic cover and/or covered with insulation you need to push away to expose the hex-headed plug. New models incorporate the anode rod attached to the base of the hot-water outlet's nipple.

4. Relief valve: Its threaded port will be within the upper 6-inches of the tank. Pull back the plastic escutcheon to expose the threaded port for inspection. A weeping relief valve can be an intermittent source as well and if no drip-leg has been installed, probing its outlet with a finger will reveal if it's damp/wet. The warmth of the tank itself can cause minute weeping to evaporate. Probing the drip-leg can also reveal dampness associated with a weeping relief valve. If wet, the water-pressure needs to be checked and that leads to investigating thermal expansion issues that may need to be resolved.

5. Elementary my Dear Watson: Turn off the power (may need to use lock-out/tag-out safety kit) and remove the electric element covers, pull off the insulation covering the thermostat and element and inspect their tank-penetration. Bolt-in and threaded both utilize a rubber gasket to seal the port. If you want to add a bit of extra value, you can restore power and use an amp probe to check the elements by adjusting either thermostat to activate the individual elements. Check voltage as well and you can determine the actual wattage to calculate recovery in gallons-per-hour if you know the intended target storage temperature and the cold-water inlet temperature. Ohms Law: amps x volts = watts. 1-watt = 3.412-Btus. Water weighs 8.34-Lbs per gallon and raising 1-gallon from 40°F to 120°F requires 667.2-Btus.

6. Drain port: Inspect the threaded port for the drain valve. Bonus points: You may have noticed the water heater in the "Dateline" episode had its factory drain valve replaced with a brass nipple and ball valve with male hose thread adaptor and it sticks out about 6-inches and has no safety cap. Pant leg catching could scald a foot. Got kids? Better have beaucoup insurance! A few seconds later, the same water heater has its factory-installed plastic drain valve in tact. The remaining video shows we're back to the brass nipple and ball valve. Oops.

7. Insulation: If nothing so far has been leaking, probe the insulation below the lower element and if it's wet, then the tank is leaking and you need a new water heater. These steps are so logical that even Spock would approve!

Hansen's expose on so-called plumbers has opened up a new chapter for the work I'm doing here at CONTRACTOR magazine: videos. This month's column has a video on the magazine's website to illustrate the process of checking an electric water heater to find the leak. As is typical for trade folks, you'll see the water heater was not as accessible as was Hansen's staged event: you and I deal with real-world plumbing adventures.

All Dave Yates material in print and on Contractor's Web site is protected by Copyright 2011. Any reuse of this material (print or electronic) must first have the expressed written permission of Dave Yates and Contractor magazine. Please contact via email at: [email protected].

About the Author

Dave Yates

Dave Yates material in print and on Contractor’s Website is protected by Copyright 2017. Any reuse of this material (print or electronic) must first have the expressed written permission of Dave Yates and Contractor magazine.

Voice your opinion!

To join the conversation, and become an exclusive member of Contractor, create an account today!

Sponsored Recommendations