Even though electric water heaters are pretty popular in homes worldwide, gas water heaters have plenty of advantages. They are more efficient, have lower operational costs, and are highly suited for colder climates. Gas heaters operate through convection: a burner below the tank heats the cold water entering the tank. But, you must first switch on the pilot light in order for the burner to work. Knowing how to light a pilot light on a water heater is crucial to getting full utility from it. If the pilot light is not lit, there will be no hot water supply, regardless of whether you have a tanked or tankless water heater.
Here are some basic questions related to the issue you might find helpful.
Where is the pilot light assembly located?
The screen of it is usually located behind the heating unit, at the lower part of the water tank. In some cases, it is covered by a panel; in others, you may be able to access it directly.
The burner and the knob are located directly above the screen, connected by a small metallic tube. Before a plumber does any maintenance work on the heater, this is the knob they use to shut off the gas supply.
Why does the light go out?
Sometimes, it goes out by itself for various reasons like broken valves or thermocouple, low gas pressure, or faulty venting.
For instance, a malfunctioning thermocouple will cause the flame to extinguish by itself. The thermocouple is close to the pilot. When you switch on the burner, it ensures that the gas line is open. A defective one will cause the flame to go out without any reason, preventing the heater from heating water.
The flame might also go out because of a defective gas valve, or in some cases, a cracked heat exchanger.
In most cases, you can restart the flame by yourself. However, if you cannot restart it despite several attempts, it's a good idea to call a professional plumber. Working with gas is dangerous and can often be uncertain.
How to switch it on?
Start by removing the outer and inner panels at the water heater's base to access the pilot assembly. Find the gas knob and turn it towards the pilot position. Press down on the knob and hold the knob, which releases the flame to turn on the gas.
Keep the knob in the on position for a minute to ensure the flame doesn't go out. Once you have switched on the main burner, you will hear a whistling sound indicating that it's working correctly.
When should you call a plumber?
Although you can switch on the flame, you must call a professional plumber if you suspect a gas leakage from the heating unit.
The best possible way to detect leakage is to stand beside the heater and take short, repeated sniffs. Do not take deep breaths. A gas leak smells similar to rotting eggs and will likely be easy to detect. Try listening for a hissing sound if you can't smell it but still suspect a leak.
You should also call a professional plumbing service if the pilot light doesn't burn or keeps going out despite the knob being turned to the "on" position. This is likely the fault of the thermocouple, which will require replacing.
If you want to use yours correctly, and save money on expensive repairs, it is essential to know how to light a pilot light on a water heater. However, in some situations, like the ones described above, it may be better to call a plumber.