Defective Igniter or Pilot Light If it clicks but your furnace won't ignite after the combustion cycle, the electronic ignition systems probably need to be replaced. In cases where the furnace ignition starts normally but only stays on for a few minutes and then goes out, a new pilot light likely needs to be installed.
Very likely your furnace has a flame sensor. The ignition control turns the main burner gas on for 3-5 seconds after the hot surface ignitor has warmed up. If the flame sensor and ignition control don't detect that the burners have lit, the main burner gas is shut off and a new trial for ignition begins.
You can reset the ignition on your furnace simply. To do this you must cut the power to the furnace first by turning off the circuit that powers it. Once the power is off you can remove the burner door to reveal the ignitor. Turn this to “off” and leave it off for at least 5 minutes.
Most likely, your furnace is making a clicking noise and not providing heat because your furnace's spark igniter is trying to ignite your pilot light or burners but is failing to do so. In other words, there's an ignition system malfunction that needs to be fixed. Otherwise, your furnace won't start.
If your gas furnace initiates the start cycle but doesn't fire up, it's likely because of a faulty, damaged, or dirty ignitor/sensor. This is a very common problem — you can try to clean the sensor and replace the ignitor.
In this article, we discuss three of the most common reasons why a furnace turns on without generating heat. These include incorrect thermostat settings, airflow problems, inadequate furnace fuel, and ignition problems.
If the igniter is glowing, but the burner is not lighting, the igniter may be weak and still be at fault because it requires a certain amount of current draw to open the valve. This check requires the use of an amp meter and should be performed by a qualified person.
Checking your thermostat is the best place to start. Make sure it's set to “heat” and that you've set the temperature higher than the current room temperature. If that doesn't resolve the problem, try switching your fan to “on” to force the furnace to start working.
The Short Answer Is: Warning signs of a bad furnace ignitor include the furnace not starting or heating, a noticeable clicking sound without ignition, or frequent short cycling where the furnace turns on and off rapidly. Additionally, if the ignitor appears cracked or discolored, it may need replacement.
Check the pilot ignition light.
(Electronic ignitions will not have a pilot light.) If your furnace clicks on or initiates the start cycle, but does not fire up, you likely have a faulty or dirty ignitor/sensor. This is one of the most common furnace problems.
Furnace Not Igniting Because of Incorrect Thermostat Setting
Make sure the thermostat is set to heating and that the temperature is set high enough to actually turn the furnace on. It may be set at too low of a temperature to activate the furnace.
If nothing's happening when you're expecting the whir of a blower, check the circuit breaker and fuse. At your electrical panel, make sure all switches related to the HVAC system are on. Reset any tripped breakers and replace all blown fuses, and your furnace should kick back on.
Furnace ignitor cost
A furnace ignitor replacement costs $100 to $250 on average. Most universal hot-surface ignitor prices are $15 to $35 for the part alone. Gas furnace ignitor prices are $20 to $100 for parts from the original manufacturer (OEM). The labor cost to replace a heater ignitor is $80 to $200.
A furnace making a buzzing sound may also be due to a faulty furnace capacitor. Furnace capacitors help regulate the power of furnace motors such as the blower motor. A failing or bad capacitor can cause a buzzing noise, more commonly in older furnaces. Call for furnace repair.
Like an extinguished pilot, a faulty ignitor prevents a furnace from heating up. Unlike pilots, electronic ignitors cannot be manually lit when they fail. However, a homeowner can take troubleshooting measures to determine if the ignitor is bad or if some other issue is causing the furnace not to blow hot air.
A multimeter can be used to help determine if a glow-bar style furnace igniter has sufficient electrical continuity – a continuous electrical path present in the part – for the igniter to function properly.
There are several reasons why your furnace may not turn on. The most common include a broken thermostat, gas line issues, clogged air filters, blocked ductwork, a tripped circuit breaker, and issues with the furnace itself.
Most modern gas furnaces can be reset by turning off the power, waiting around 20 seconds, then switching the power back on. Other furnace models may exit lockout after 1-2 hours and attempt to power on again.
The first motor to come on will be the inducer motor.
Not a large motor by any means, but it's the one that gets rid of the fumes spent by the flame that warms your home. The control board and a pressure switch acknowledge that the inducer has come on and is working properly.
You may have an ignition system or fuel supply issue if your furnace doesn't produce heat after turning it on. You can check if you have fuel issues through the following steps: Look at the gas supply line to make sure the gas valve is open. Make sure that your tank has enough fuel if you use oil or liquid propane.
Reset The Furnace Ignitor
Find the burner door on the furnace and look behind it to find the ignitor. Turn it to “OFF” and wait for five minutes. After you wait, turn it back on and return the door to the burner. It is important to make sure the switch on the door is properly engaged.
The furnace gas valve on off switch has to be in the ON position to ensure it is getting power. The switch should look similar to a light switch and will be located on or near the furnace. The handle/knob for the gas valve runs parallel to the line when in the ON position, double check that it is in this position.