If this is your first time turning on your furnace this season, keep in mind that it may take a little extra time for the pilot light to turn on. The air conditioner works good and the fan also but nothing from the furnace … The last common reason for a furnace not kicking on is a dirty air filter … Start by turning the furnace off, turn your thermostat to “fan only,” and wait a few minutes. They are expensive but very much needed in a home or business. Get up-to-date current news, promotions and industry tips. About 4-5 times now when it called for the furnace to warm up the house to 68 f the furnace has not come on. Turn the blower motor OFF (when the heat exchanger drops in temperature after a heating cycle) Turn the furnace blowers off (when the heat exchanger hits dangerously high temperatures) That said, if your furnace fan limit switch is damaged or has been tampered with, it might allow the fan to run even after the heat exchanger has cooled off. In 90% of cases, that’s the issue at hand. Problem: It clicks on, but doesn’t fire up. The pilot and gas burners start, but the fan does not. Once the furnace starts, it should shut off when the desired temperature has been reached. Learn more about bad capacitors by checking out our blog, “My AC Just Hums and Buzzes But Doesn’t Turn On”. It is a Duo-Therm. If your furnace isn’t running, you can check out the igniter portion to see if it isn’t producing enough heat to light a flame. So, if you are questioning “what to do if my furnace won’t turn on” here are some reasons for your furnace not working. If the ignition system does not work properly, then neither will your furnace. I toggle my dometic digital thermostat to furnace, I hear the relay in the overhead fan click, the blower start, and within 5-10 seconds the igniters ignite and hot air is blowing out of the ducts. Required fields are marked *, You want to make sure you are warm this winter if you live in. When your furnace blower wheel is broken, it will make your furnace sound like metal scraping against metal and will really hurt your ears! So the control unit didn’t think the pilot flame had been lit. … The house is built in 1950 but I suspect this furnace is a lot newer judging from its look. If you see or hear the fan turn on, your blower motor is not the culprit. It tells us whether your furnace is burning too much gas. 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. Clogged air filters may cause your furnace to turn off as a safety feature. If all else fails, check the furnace’s gas valve to make sure that it … If your furnace won’t kick on, check the pilot light. If your filters are clogged, clean them out and try your filter again. Check the Standing Pilot. This might be because your thermostat is actually on the wrong setting. More or less. When I turn on my furnace it doesn't start but there is a click from the air conditioner. My hunch (but I am not an HVAC pro) is that the fan is fine because it works in "on". Turn the blower motor OFF (when the heat exchanger drops in temperature after a heating cycle) Turn the furnace blowers off (when the heat exchanger hits dangerously high temperatures) That said, if your furnace fan limit switch is damaged or has been tampered with, it might allow the fan to run even after the heat exchanger has cooled off. If your furnace clicks on or initiates the start cycle, but does not fire up, you likely have a faulty or dirty ignitor/sensor. Clicks at least 10 times, but then starts up. The fan blower should come on. Have you ever seen your blower capacitor? Nothing, click...then a very light hum....for a minute or two...then it goes off. Turn the appliance off, wait 30 minutes for it to cool down, then press “reset.” If the furnace doesn’t reset immediately, repeat the procedure twice more. FAN DOESN’T RUN - The furnace fires, but the blower does not start.. After the burners have ignited, the next step in the heating cycle is starting of the blower motor. I bought an old house and one of its rooms is equiped with a direct-vent gas furnace (Perfection-Schwank, Model ASV712RTN Version T). The furnace clicks but doesn’t turn on. These conditions can be caused by what is known in the HVAC industry as “short cycling”. If the furnace starts, the problem is either with the thermostat wire or thermostat. If you hear this sound, turn off your furnace immediately. The problem in my system was the flame sensor wasn’t working. It can range from super simple to very complex. My furnace all of a sudden , when it trys to come on (or if you raise the thermostat) you here a click sound and it sounds like its wanting to start up, but doesn't. Odds are you have batteries in the stat that still make the clicks thinking it is working. Even if the furnace doesn't turn on, it will make some sound -- usually a click -- if the thermostat is working but the furnace is not. When the furnace hasn't been on for a few hours, it takes a while to start up. If you furnace filter is clogged, the airflow will be restricted. The draft switch closes to prove the draft fan is working. The pilot flame may not be hitting the thermocouple properly due to an incorrect mixture of gas and air. Some more observations: I attempted 6 times tonight to turn on the furnace and observe. This will be done either by a heat-activated switch or internal timing of a control board. When the thermostat warms up, it tells the furnace to shut off. This is typically the problem if you can hear your furnace click on but it does not fire up. When I turn on my furnace it doesn't start but there is a click from the air conditioner. Also tried swapping them with the AC wires, which makes the blower turn on but no heat. You will most likely need to replace this part on your furnace, but don’t worry, it is a fairly easy repair and can usually be done in an hour or so. Newer furnaces that use electronic ignitions an develop dirt and dust buildups inside the system, which stops the ignition sequence from starting the system. Make sure that your furnace switch is “ON” the furnace blower compartment door is on and secure. If you hear a clicking noise followed by a soft hum or buzzing noise but your outdoor unit doesn’t turn on, you probably have a bad capacitor that needs to be replaced. A thermocouple is a flame sensor that, when it detects a pilot flame, opens gas valves to the furnace burners. If the fan does not start, you have a wiring issue (circuit breaker trips) or … When it does turn on, it won’t stay running very long, usually only a minute or less. I turned off the gas switch, waited, turned it back on and nothing. We see several homeowners asking this question: “Why is my furnace making a clicking noise and not producing heat?”. To put the ignition system in context, here’s your furnace’s order of operation: As you can see, if there’s a malfunction at step 4, your furnace won’t open the gas valve, and the burners won’t light. NO – If the icons or messages aren't flashing, this means your heat should be working. Likewise, when the heating coils warm, the control switch kicks the blowers on … Your igniter may be glowing bright orange, but if it is on with the gas valve and not igniting, it is likely too weak. The clicks I was hearing was the unit continuing to spark the gas. The condensate pump works. If you own a furnace that operates a pilot light, the operation is similar, but the control board doesn’t trigger the ignitor. Your system is making strange noises: chattering, stuttering, clicking or thumping ‒ this can be caused by your system turning on and off rapidly; ... but your system doesn’t turn on. And probably not a limit switch because the system (from what you've described, and similar to what I experienced) runs despite not having the blower running. However, some furnaces continue working even past this, which can be dangerous. Ok, first we want to make sure the furnace has power. I toggle my dometic digital thermostat to furnace, I hear the relay in the overhead fan click, the blower start, and within 5-10 seconds the igniters ignite and hot air is blowing out of the ducts. This problem is especially troublesome when you are not getting heat at some point during the very cold winter months. Replace the wire or thermostat to fix the problem. Some causes of a shut gas valve include: All of the above are issues a furnace technician needs to fix. Now, let’s talk about that clicking noise. 4 of the times, I just got the click and ensuing "buzz". Once the pilot light is lit, the furnace is controlled by the flow of gas alone. There is a condensation pan on the furnace that collects excess water and if the reservoir is full the furnace won’t turn on. A repeated clicking indicates a failure/system malfunction. And not the thermostat since it calls for heat and at that point the fan is under furnace control. Solution: This is likely due to a faulty or dirty ignitor/sensor. No gas = no ignition. Most common furnace in Southern Illinois is a forced air, gas furnace. Here are some troubleshooting tips for fixing your broken furnace: If these tips don’t work then give us a call or find us on Facebook. most furnaces have an on/off switch (like a light switch) that has a fuse inside the switch. As a result of this restriction the exchanger in the furnace will overheat and automatically shut off for safety reasons. Even when you play with the thermostat, the furnace won’t kick on. If this is your first time turning on your furnace this season, keep in mind that it may take a little extra time for the pilot light to turn on. … © 2020 Coolray Heating & Air Conditioning all rights reserved. He also advises making sure the set point is at a temperature that will actually turn on the furnace. RSP Heating and Cooling is the best company to go to for furnace repair and maintenance. Tie the red and white wires together, and switch the power on. How to diagnose a bad capacitor: If you hear a clicking noise followed by a soft hum or buzzing noise but your outdoor unit doesn’t turn on , you probably have a bad capacitor that needs to be replaced. 3. This will be done either by a heat-activated switch or internal timing of a control board. Gas and Oil Home Heating Furnaces - Furnace doesn't ignite - I have a Lennox furnace, model G20Q3/4E-100-5. It can be frustrating if your furnace won’t turn on. So if the gas valve is shut, the spark igniter has nothing to ignite and just keeps sparking. When you hear the furnace turn on, put your hand in front of the vent. Your furnace has a dirty flame sensor In this blog, we’ll go into further explanation about how the above reasons can cause your furnace to not turn on.