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How to Detect Hot Water Heater Leaks

Water heater leaks are usually quite obvious and you will discover substantial amounts of water on the floor around your heater. Normally, the first sign of a heater problem is water dripping from the bottom of the jacket. This indicates that the tank has corroded through. The cure may be installation of a new heater, or you may be able to repair the leak.

Read: Water Heater Leaking from the Bottom?

Before turning off water to water heater try to locate the source of the leak (it may not be the water heater leaking).

To attempt to locate the source of the leak first check the top of the water heater. If the top of the water heater is wet, check the water lines leading from the wall to the top of the water heater. There will be two water lines. The line on the left is the hot water line. The line on the right is the cold water line.

If water is leaking from hot or cold water lines your water heater should be okay. If the water heater is dry on the top, check the hose bib (place where hose can be hooked up) at the bottom side of water heater. If the hose bib is dry the water heater needs replaced. Before turning water off to a gas water heater. TURN OFF THE GAS.

To turn off the gas. On left of water heater (usually on left) is a flexible gas supply. Follow the gas supply back to gas shut off. Turn the lever on the gas shut off 1/4 turn. The gas is now off.

Before turning off the water to an electric water heater you must turn off the circuit breaker to water heater.

To turn off the water to the water heater, locate the cold water line at the top right of the water heater. Follow the cold water line from the water heater toward the wall. There should be a gate valve on that line. Turn the handle on the gate valve clockwise until it stops.

If the gate valve is stuck open or there isn’t one, the entire water system to the house will need to be shut off. To shut off the entire water system check for the gate valve at front of house. The gate valve has a round handle. Turn the handle clockwise until it stops. If gate valve is stuck or there isn’t one you will need to shut off the water at the water meter.

The next step is to drain the water heater. You will need a garden hose and adjustable pliers. At the bottom front of the water heater there is a hose bib (a place to hook up garden hose). Stretch the garden hose out making sure there are no kinks in it. Screw the garden hose on to the hose bib. The garden hose must be lower than the hose bib to function properly.

To open the hose bib. Turn the handle (if there is one) counter clockwise until it stops. This will be a few turns. If your hose bib does not have a handle and is a round plastic fixture. Grab the fixture and turn it counter-clockwise a few turns. There will not be much water draining through the garden hose if any.

You will need to displace the water with air. To do this, find the closest fixture (kitchen sink faucet, bathroom sink faucet, or tub/shower faucet). Open the hot side only. This will allow air into the water heater and cause it to drain.

If the water heater does not start draining, close the faucet at whatever sink you turned on. Turn the water back on to the water heater (the valve above the water heater). Be sure to turn it all the way on, you need the pressure. Now water should be draining from the garden hose rapidly.

What you are doing is clearing the hose bib of sediment so it will drain. Continue to drain in this fashion for a few minutes. Shut the water off at the water heater and open whichever hot water you opened earlier. The water heater should be draining .It may be slow, just let it drain.

Water Heater Will Not Drain?

You must wear goggles, thick gloves, and protective clothing while doing this repair!
Tools you will need:

  • 1- 14″ pipe wrench
  • 1 pair 12″ adjustable pliers
  • 1- 10″ screw driver(optional)
  • 1- 3/4 x 5″ galvanized nipple
  • 1-3/4″ fip x male hose adpt.
  • 1-low top bucket

Screw the hose adapter onto the galvanized nipple and have the bucket ready to catch any water that starts running out of the water heater.

If after following the instructions outlined above and the water heater does not drain, close the hot water faucet you opened earlier. Remove the garden hose from the hose bib. Carefully remove the hose bib from the water heater.

There are several different types of hose bibs on water heaters. If your water heater has a round plastic hose bib. Turn the hose bib counter clockwise until it comes off. You may have to pull on the hose bib to get to get it out. Be careful. There is going to be hot water in the water heater.

Water will be slowly running out of the water heater into the bucket. After removing the round plastic hose bib, there will be a pipe nipple still in the water heater. Using your pipe wrench. Remove the nipple by turning it counter-clockwise.

As soon as you remove the pipe nipple from the water heater, replace it with the nipple you have put the hose adapter on. Attach the hose to the adapter and open the hot side of the closest faucet and let it drain.

If your water heater has a hose bib that has a knob on top. Just remove the hose bib with your pipe wrench and replace with the galvanized nipple with adapter. Follow instructions outlined above.

Michael Joseph