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Water Heater Flashing Blue, Green, Red Light – What to Do?

Water heater are one of the most necessary equipment needed for our daily life. It can provide you with hot water in cold conditions and spare you from using cold water.

Today, we are going to discuss and find out what it means when the blue, green, and red light of water heater start flashing and what the solutions are for this.

Why is my water heater flashing blue light?

The water heater can start flashing blue light because of faulty parts. The list of faulty parts includes a switch, a fan, an exhaust vent, and a vapor sensor. One can solve this problem by replacing or repairing these parts. The number of flashes caused by each part will be different.

There are a lot of reasons why your water heater might be flashing blue light. Let’s discuss in detail about them.

Faulty switch:

Your water heater will flash its blue light three times if any switch of water heater becomes faulty.

Faulty exhaust vent:

Faulty exhaust vent also cause your water heater to flash its blue light. The number of flashes will be three.

Faulty fan:

When the fan of your water heater becomes faulty, it will flash its blue light at least three times.

Faulty vapor sensor:

The water heater will flash its blue light if the vapor sensor becomes bad. The number of flashes in this case will be seven or eight.

What does flashing blue light 3/7/8 times mean on water heater?

The water heater can start flashing its blue lightly suddenly due to faulty parts. But the number of flashes will differ according to the part that has gone bad.

For example, the water heater will flash its blue light exactly three times if switch, exhaust vent or fan have gone bad.

But the number of flashes will be different for other parts. The blue light of the water will be flashed seven times if the flammable vapor sensor goes bad.

But the number of flashes will increase by one if the thermostat well and its sensor go bad.

How to fix water heater flashing blue light?

There are some steps and methods you can follow to fix water heater flashing blue light. Let’s discuss in detail about them.

Repair the switch:

You can fix the problem of flashing blue light by repairing or replacing the faulty switch that is causing it.

Repair the exhaust vent:

Another part that might need repairing is the exhaust vent as it causes the water heater to flash its blue light.

Replace the fan:

The fan of the water heater has to be replaced if it is responsible for the flashing blue light.

Repair the vapor sensor:

The flammable vapor sensor of the water heater sometimes need a repair job as it can cause the water heater to flash its blue light. A faulty vapor sensor should be repaired or replaced immediately to stop the flashing problem.

Why is my water heater flashing green light?

The green light might start flashing when some parts of the water heater become dysfunctional. A faulty thermopile, a faulty temperature sensor or a faulty gas control valve can be the reason behind the flashing green light in water heater. Repairing and replacing the parts can solve the problem.

There are a lot of reasons why your water heater might be flashing its blue light. Let’s discuss in detail about them.

Faulty thermopile:

The green light of your water heater will flash if the thermopile becomes faulty. The number of flashes will be two per three seconds.

Faulty temperature sensor:

Faulty temperature sensor is also known for causing the water heater to flash its green light. The number of flashes will be five per three seconds in this case.

Bad gas control valve:

The most common cause of flashing green light in water heater is a faulty gas control valve. The water heater will flash its green light at least seven times when one of the gas control valves goes bad.

What does flashing green light mean on water heater?

Flashing green light on water heater can mean a number of things. The thermopile and the gas control valve works together on a water heater.

When the thermopile becomes faulty and it cannot produce adequate amount of millivolts, then the water heater becomes dysfunctional. It causes the water heater to flash its green light several times to let the owner about the condition.

Another important part of the water heater is the temperature sensor. If one of the temperature sensors becomes bad, then the green light with start flashing to signal about the problem.

Moreover, the water heater will relentlessly flash its green light if a gas control valve goes complete bad. So the green light actually saves you from further damage by letting you know about the internal problems.

How to fix water heater flashing green light?

There are some steps and methods you can follow to fix water heater flashing green light. Let’s discuss in detail about them.

Clean the thermopile:

Dirt and dust build up inside the thermopile can often make it dysfunction and can cause the water heater to flash the green light. You can clean the thermopile to solve the problem.

Replace the thermopile:

If cleaning the thermopile does not do the trick, then you will need to replace it with a new one to stop the flashing green light.

Repair the temperature sensor:

Repairing the temperature sensor can most often than not solve the problem of flashing green light. If you cannot repair, then replacing it will be more feasible.

Replace the gas control valve:

Gas control valves are the most common cause of flashing green light in water heater. You will have to get them replaced with new ones to stop the water heater from flashing green light.

Why is my water heater flashing red light?

The red light of the water heater can begin flashing because of normal operation. But, the number of flashes will increase if the flame sensor rod and the gas control valve become faulty. The flame sensor rod has to be cleaned and the gas control valve has to be replaced to solve the problem.

There are a lot of reasons why your water heater might be flashing red light. Let’s discuss in detail about them.

Normal operation:

The water heater will flash its red light to signal you about the normal operation of the water heater. The number of flashes in this case will be one per three seconds.

Faulty flame sensor rod:

The flame sensor rod of the water can become faulty due to corrosion and rust. The water heater will flash its red light to let you know about the condition of the flame sensor rod.

Faulty gas control valve:

If any of the gas control valves become faulty, then water heater will flash its red light to let you know. The number of flashes will be seven per three seconds. This signal should not be taken lightly.

What does flashing red light mean on water heater?

When the water heater flashes the red light, it can mean a number of things. Most of the times, the water heater flashes its red light when it is fully functional and doing its job perfectly.

Other times, the red light of the water heater might flash due to faulty parts in the system.

One of the major reasons why the red light might flash excessively is when the flame sensor goes bad due to corroded rod.

The gas control valve is another crucial part of the water heater and it is believed by experts that flashing red light indicates at a faulty gas control valve.

How to fix water heater flashing red light?

There are some steps and methods you can follow to fix water heater flashing red light. Let’s discuss in detail about them.

Clean the flame sensor rod:

Cleaning the flame sensor rod can solve the problem of flashing red light in water heater. A sandpaper will be handy to implement this process as it will be able to clean off any corrosion and rust from the flame sensor rod.

Replace the flame sensor rod:

If cleaning the flame sensor rod does not fix the flashing red light, then you will need to replace it with a new one. It might save the day and your water heater.

Change the gas control valve:

Changing a faulty gas control valve can solve the problem of flashing red light in water heater. You can seek the help of a professional in this case for better success.

Final Thoughts

The water heater can start flashing blue, green, and red light if any part of it becomes faulty. Gas control valve, thermopile, temperature sensor, flame sensor rod, exhaust vent, fan are some of the parts that cause the flashing light issue in water heater. These parts can be repaired or replaced.