How to check hot water heater thermostat

How to Check the Thermostat on a Hot Water Heater. There is no hot water in the water heater thermostat, indicating a problem with the upper thermostat. And the problem with the lower thermostat is the malfunctioning. The short cycling can cause the thermostat to be broken on the electric water heater, locate the reset button.

The color of the rest button is often red, and it is placed near the thermostat. It can be located inside the metal covering or some other insulation. The majority of water heater is among 8 to 10 years. After ten years, you should replace the water heater thermostat.

The heater malfunction is also causing the thermostat failure. When the resistance in the thermostat is high, it is due to the loose wire. It might ignite the heating element. because of the open connection with the water heating elements

How to Check Hot Water Heater Thermostat 

The water heater thermostat is tested with the help of the thermostat. Attach one of the multimeter probes with the grounded terminal and then the terminal of the thermostat and with the heating elements terminal. So the multimeter shows no voltage at all. The failing thermostat gives the incorrect reading. And it produces noise from the engine.

The heater malfunction is also causing the thermostat failure. When the resistance in the thermostat is high, it is due to the loose wire. It can cause a fire to the heating element because of the open connection with the water heating elements.

When the electric water heater is not producing hot water, it is because the fuse is blown or the circuit is tripping. While some of the electric water heaters have a safety style near the thermostat which avoids this problem.

  •  The heating and cooling system gets off
  •  The temperature reading is inaccurate
  •  Spikes appear in the electricity bill
  •  Temperature fluctuation appears mostly
  •  As thermostats age

If the thermostat is not working, shut off the breaker and open the cover. Use the brush to clean it if it becomes dirty inside. When the water heater keeps tripping, it may be due to a broken element. The thermostat is the main component of the water heating elements, so the water heater cannot work without it.

The thermostat tripping is the faulty reset button or making the loose connection of the wires, so this causes the short circuit. If the water is exposed to it either directly or indirectly, it will seriously harm the system and the person. Check the metal casing if the reset button keeps tripping on the thermostat.

Testing the Electric Water Heater

Most electric water heater has two thermostats for managing the heating element. The thermostat consists of the upper and lower half. The upper half goes terrible when it gets no hot water. And the lower level of the thermostat gets damaged when there is minimal hot water in it.

The thermostat is tested to check which component requires replacing, and the water heater starts working again. Both thermostats in the water heating element are not the same; when one gets damaged, the other one does not continue to work the same.

Step 1

Turn off the breaker that is available inside the Inner service panel.

Step 2

Apply a screwdriver to the upper and lower access panels to remove them. The access panel is usually on one side of the thermostat. The thermostat is generally covered with insulation, but when it is pulled off, use the tape to make it secure.

Step 3

The insulation covering the thermostat removes it but does not pull away the heating element and insulation wires.

Step 4

Make use of the screwdriver for turning the temperature to a high setting.

Step 5

Place the probe of the multimeter directly on the white terminal and the other search of the multimeter on the upper side of the white airport. The multimeter shows the zero reading. The upper-level thermostat contains fewer cables. Then set the temperature to the lowest setting with the help of the screwdriver. Place the probe of the multimeter on each terminal of the lowest thermostat.

Step 6

Replace the damaged thermostat and put the insulation back on the thermostat. Then replace the cover with the help of the screw. For activating the water heater thermostat, turn on the breaker.


The thermostat in the electric water heater is like the tankless water heater. The testing and fixing of the water heater thermostat require only a few tools: a multimeter and a screwdriver. You can test the thermostat with essential knowledge, which requires Turning off the thermostat’s power and Testing the unit.

When any problem with the thermostat appears while testing it and replace the thermostat, with the help of testing, you will find the problem with the thermostat. When the water heater is not producing that water, there may be two reasons behind it.

The faulty thermostat or the faulty heating elements. And you can fix these problems with the help of the old. It also causes changes in the temperature, which saves them money.

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