How do I know if my flame sensor is bad?

How do I know if my furnace flame sensor is bad?

Switch off the power to your furnace.
Close the gas valve.
Take out the mounting screw.
Carefully pull out the sensor.
Inspect the sensor: if the insulation is intact but appears sooty, burnt or slightly corroded, it might only require cleaning.

How much should it cost to replace a flame sensor?

If they are part of a routine maintenance service, they will cost about $200. Similarly, flame sensors often become too dirty and malfunction, but these sensors can be fixed with a thorough cleaning. However, if it’s too far gone and you must replace the flame sensor, it will cost you anywhere from $80 – $250.

How much does it cost to replace a furnace flame sensor?

You can expect to pay between $350 and $500 for a new flame sensor if you call a furnace repair company.

What causes a furnace flame sensor to get dirty?

What Causes a Flame Sensor to Get Dirty? It’s possible for a flame sensor to go bad; but more often than not, it is not broken, just dirty from carbon buildup. Because a flame sensor has a very low tolerance for variations in the reading it takes, the slightest coating of carbon can cause it to misread and shut down.

Can you bypass flame sensor?

In short, you cannot bypass the flame sensor and manually light your furnace. Bypassing safety controls, even when possible, should never be done. Instead, you should try cleaning or replacing your flame sensor to get it and your furnace back to good working order.

What symptoms would a furnace with a dirty flame sensor exhibit?

Signs of a bad furnace flame sensor are:

The furnace lights but then shuts down after a few seconds (short cycles)
The porcelain on the flame sensor is cracked.
The flame sensor is sooty or corroded.

How long do furnace flame sensors last?

Generally speaking, the flame sensor should be replaced every two to three years as preventative maintenance. Some technicians also recommend changing it any time that there is a flame current issue.