The last thing anyone wants on a frozen winter morning is a cold shower. Knowing how to perform your own hot water heater repair can save you a great deal on service costs, especially since the replacement parts you’ll need don’t usually cost much.
In this article, we’ll discuss the basics of how to fix your water heater, whether you have an electric or gas model.
Tools You’ll Need
Before starting any hot water heater repair project, you’ll need to make sure you have the right tools for the job. These will typically include:
- Non-contact voltage tester (available at most hardware stores for about $5 to $10)
- A pair of needle-nose pliers
- A 4-in-1 screwdriver
- An element wrench (for electric heaters)
- A wrench set or adjustable wrench
- Long matches (for gas heaters)
Electric Hot Water Heater Repair
Electric water heaters are very simple and straightforward, so repairs are typically easy to do on your own. Before you start, though, there are a couple items to check:
- The circuit breaker – check to see that the breaker switch for your water heater hasn’t flipped
- High temperature cutoff valve – this is located above the upper thermostat and can be reset by pressing the red button
If neither of these solve the problem, you most likely have a bad heating element.
Replacing the Heating Elements
Each electric water heater has two elements, one at the top and one at the bottom. Each is controlled by its own thermostat. The lower one tends to be used most, with the upper one kicking in when you have heavier heating loads.
Your heating elements can be tested with a continuity tester. Just remove the paneling over each one and touch the tester wire ends to each pair of terminals. If the tester doesn’t light up, you have a bad element.
In addition, you should test for short circuits. Do this by touching one wire end to one terminal while touching the other end to the tank’s exterior. In the case of a short, the current will flow through the tank, so if your tester lights up, you’ll know that one of the elements has shorted out and needs to be replaced.
If it turns out you have a bad element, it’s pretty easy to replace. Before you begin, make sure to shut off the power to the water heater to avoid any rude shocks during the repair process. Once that’s done, turn off the cold water supply valve (at the top of your unit). Drain the tank by running the hot water from any nearby faucet while opening the drain valve on the tank (attaching a hose leading outside prevents you from soaking your floor).
Once the power is off, pop out the bad element with your element wrench and a screwdriver, thread the old one out, and thread the new one in. Replacement elements are cheap ($10 to $20 each), but make sure you get ones with the same wattage. Detailed pictures can be found here.
Replacing the Thermostat
If it turns out your elements are still good, you may have a problem with the thermostat. Testing for a bad thermostat is a complicated process, but replacements are pretty cheap, totaling to under $20 for both.
Again, make sure the power to the unit is off before you begin. Remove the paneling over each thermostat (they should be the same ones that cover the elements) and take a look at the wiring. Make some quick notes of which wires connect where.
Disconnect the wires from the thermostat and gently pry it from its bracket. Take care not to damage the brackets, but if they do get damaged, they’re cheap to replace as well. Replace each thermostat with as similar a model as you can find (ideally the same brand and model). Reconnect the wiring, and you’re good to go.
Gas Water Heater Repair
Gas hot water heater repair is vastly different from that for electric units, but they’re still pretty straightforward. The most likely issues with a gas water heater are the pilot light and the thermocouple.
Relighting the Pilot Light
First, try relighting the pilot light with a long match. Your water heater should have instructions printed on the side on how to do this. If it takes a light and continues burning, then the problem is solved. However, if it won’t light or remain lit for long, then your problem is most likely with your thermocouple.
Replacing the Thermocouple
The thermocouple serves as a safeguard, and it will shut off gas flow to the burner if it doesn’t sense heat from the pilot light. On most models, the thermocouple is easy to access. It should be near the bottom of your water heater.
Before you replace the thermocouple, make sure you shut off your gas first to prevent any accidents. The only time when you should smell gas is a small whiff when you unhook the lines. If you smell it at any other point, leave your house and call your gas provider.
Once your gas is off, remove the nuts on the pilot, gas, and thermocouple lines. Pull out the whole assembly, unscrewing the nuts holding it in place, and replace the old thermocouple with a new one. Make sure it’s the exact same model as you do so.
Take special care to place the new thermocouple exactly as the old one was, with the bulb right where the pilot light’s flame burns. Also, when replacing the assembly and reattaching the lines, don’t over tighten the nuts since they’re made of softer metal.
Note on Professional Hot Water Heater Repair
If these repairs don’t work or if you have a model that doesn’t have easy access to the parts you need to replace, it’s typically best to call a professional to do the job.
Major hot water heater repair work can be covered with a home warranty. Take a look at the different plans available to determine which options would work best for your home.