Indoor Fan Keeps Running - 10 Reasons Why

[@randydavidson7969]

By far best video I have seen. Made it very easy to understand…

[@marciniakcrystal]

😊😊

[@johncobb2246]

Nice video thanks

[@teebob21]

This video saved me a $300 service call in the middle of an ice storm. I have a 30+ year old propane furnace that had a stuck limit relay...fixed with a little percussive maintenance!

[@dpuetz]

I have watched a lot of self-help uTube videos, I am a handy guy, but this video and this guy are the best I have watched. Very understandable, very safe advice, and thorough. Thank you Sir !!

[@TheHawgfarmer]

This guy is amazing to say the least. So many times I have watched these videos hoping to find solutions an never any luck. But this guy? If.he didn't cover your problem U would say, you need a new furna. He is thorough without being a bore. Informative and doesnt leave you thi king, C'mon man, get to the point. Y like others I would say e everything he says tou need to hear. No rambling.and.he gets right to the point. No process elimination and definitely no guesswork. I will say it one more time, If he didn't offer you the needed advice and the simple.way to fix it? You need a new furnace. Thank you so very much. I feel like I have been fully trained in furnace repair. I could.go in to business with just this video. Amazing knowledge and free of charge. I feel like I should pay him for his knowledge. I would say I would like to see more videos from.this guy on this topic but I honestly think he covered everything I could possibly need. Tha k you again and God bless you for sharing you knowledge and expertise in this field. JUST WOW!!!

[@Chow_Yun_Matt]

Agreed, I watched about 20 other videos trying to solve my problem before I came across this one. Subscribed, and will be my first go-to in the future!

[@odi1964]

This is what I'm looking for an HVAC technician, a detailed step by step diagnostic check. Unlike other tech guy who jumps to the circuit board as the main problem for a continuously running blower fan. Salute to you brother!

[@tedkobel5002]

Thanks for this video. I looked at about 4 others to find possible answers to my blower continuously running and checked all the things recommended. None worked for me. This video was the only one that mentioned the fan relay and rapping gently on it to loosen a possibly stuck contact. Sure enough, that was my problem. All is well now. I'll be looking to find a replacement relay. Meanwhile, if it sticks again, I know what to do. This young man is the best!!

[@darrinjt1]

Best channel ever. This video saved me big time . My heat was out for 2 days tried everything to figure out . And turn out to be my high limit switch was stuck in the open position, tapped it a few timed and my furnace started working again and said me money insteadof calling someoneto fix it.. thank you so much for making these videos and keep up the good work helping people

[@Holpopov]

You have no idea how much I appreciate you making this video and sharing valuable information.

[@shaneswift7501]

THANK YOU for posting this video, followed step by step and discovered it was a stuck relay on the MB. There is NO WAY I could have narrowed it down without your video, you saved me time, you saved me money, and now I know where the problem is I can grab a new MB and be ready in case it becomes a more common issue. If this video helped anyone you owe it to this guy to subscribe and use his amazon link, I will be!! Not only was this amazingly helpful, there was not 20 adds to skip through.

[@billf23351]

You saved me a visit from AC tech. Yesterday with my AC not turning on, the tech had to replace the Condenser Contactor. Great, ac then works. Then this morning, I saw that the blower fan would not stop despite temp desired having been reached. I then realized that your very 1st troubleshooting item of the fan being on instead of on Auto was the culprit! So I do not need another visit from my AC tech, who had left the fan setting on. Thanks again!

[@GrahamBrannon]

Your tip on checking the high limit switch being stuck open by giving it a smack was exactly what my furnace needed! Thanks for the video!!

[@lonthrall5613]

Got it on the first one! The thermostat was "operated" by someone desparate for heat because the furnace mounted switch had been unintentionally turned off! Really appreciate your videos! Thank you! BTW, this isn't the first time you've been instrumental in helping repair "this old furnace"!

[@philo6571]

You are amazing! Spent hours following information from other sites without any progress. With in 5 mins of watching this I got my heater working. Not one of the other sites mentioned the trick with the stuck heat limit switch. Thank you so much!

[@555mouser]

Add this video to one more reason why KZbin is great. Thanks for the great video. Good quality. Detailed and well edited. Thank you. You helped someone in need today!!!

[@kcmgfarm2389]

Man, this was an excellent video. I know nothing about air conditioning or air handlers but I could follow along easily. I know you are teaching via You Tube and it's very much appreciated.

[@ShiaCrescent]

Reason number 4.Tripped flame rollout switch, thank you my good man. In fact it has inspired me to watch the video you made dedicated just for that topic alone. Keep doing what you are doing and once again we all thank you!

[@frankhopkins5165]

How you can make this so simple and straight forward is absolutely amazing! Great job and THANK YOU!

[@bobsmith9938]

Just want to take a minute to thank you and thank you KZbin. I fixed my furnace, Probably saved $500 - $1500. Control board was blinking 3x and induction fan kept going on and off itself. Armstrong furnace. I’ll explain the price range shortly. But it’s your video and another video that really helped after watching about 10 videos! You and this other person explained it very well. With that basic knowledge and understanding of functions, I was able to isolate the problem. Thanks again, read on for details :) If you have the will and ability to problem solve and research, it will save you a lot of money. So $600, the technician said was my problem, the control board. I said all you have to do is unplug and plug things, I can do that myself but since you’re here can u give me a better price. And the key question, “is this going to fix it?” I understand the answer, but I don’t like it, “we will only know once we do it”. I felt this was a fix but will lead to other issues/charges. So I paid their trip/diagnostic charge, thank u. I bought and swapped the control board myself. Control Board only $125. Dedicated about a day to educate myself. Found out, it was NOT the control board, so I have a spare now, in case. Turned out to be a short in my thermostat wires. Lucky for me it was right where the furnace was, I don’t know if the installer or other technicians that came before & did this on purpose but there was an open wire touching the side of the furnace. This is the furnace side close to the wall, so it was kind of tucked in between. I felt wow this is HVAC milk money, like a shady ponzi mechanic. But then again, there’s a slight chance it was random. Also want to mention the companies that I called are all 4-5 star, google reviews with many reviews.

[@jamesbender1967]

I'm an HVAC tech (not backwoods self taught- accredited HVAC school grad) this is somewhat common for the vibration of equipment to cause chaffing and rubbing of wires. This is why there is a Romex coming through the housing of the furnace, also thermostat wires coming through housing has a plastic tabbed bushing to help prevent this. There are unscrupulous companies, just like mechanics, who do some shady things sadly.

[@HJG-1019]

*WOW!!!!!* I am having this same problem and have looked up a zillion articles online and tons of videos on YT -- and *YOURS* by far is the *BEST!* The most informative, the easiest to understand (and the _most enjoyable_ - if l may call it that!) *Thanks for taking the time to share your knowledge and wisdom with us all!*

[@masonwang9051]

You said exactly what I want to say. I am still watching his other videos and learning, and hope he can consult online helping to solve my furnace problem, as I live in Boston

[@HsingSun]

@@masonwang9051 In Boston, you you need cooling?

[@HermosaJammer]

Absolutely awesome info! Your my go too for all HVAC and home repairs. Your delivery always has a sequence of operation that is easy, understandable and always educational. No way I would tackle or feel confident on the home repairs that I’ve done without your help. Keep up the great work and look forward to more videos!

[@WordofAdviceTV]

I'm happy to hear that my videos have been helpful! Thank you for watching and leaving a comment!

[@robertzino9345]

Literally just whacked at the control board a couple times and the thing started working....YOU ARE A GENIUS!

[@WordofAdviceTV]

Haha gotta love it when that works :) Glad to hear you got it fixed, stay warm!

[@billybbob18]

I'd shop for a control board if I was you. If it did that once, then it will probably happen again soon. That's the way that sort of problems go. I did the whack treatment (I call it "the fonzerelli") to a gas valve 6mo ago and the customer still has heat. They were cheap and chose not to order a new one. The older the component, the more luck you'll have with the shock treatment.

[@dellappin87]

One of the best teaching videos and teacher I have ever seen. Excellent, and I want to watch more, even if I don't need to. Thank you.

[@lk5629]

OMG, I was ready to get ac serviced. I watched this video and followed instruction to make sure your thermostat is on auto for fan and not on a speed setting. I checked and it was on med/ hi so I put it on the auto setting and the blower finally stopped. Thank you so much.

[@MAMAlbertaGirl]

You are an amazing teacher! Your explanations are simple but thorough, your hand gestures help the viewer understand and you give a close-up example of the parts for each reason…and notes! You are the best. Thank you so much!

[@aceagui1129]

Hey man you’re very good, I’ve been doing AC for over 18 years you keep impressing me you cover every detail, you are a very good instructor you have impressed me, your are the first in 10 years, I’ve like that you cover just about every corner. I have guys calling me for help all the time, well I’m going to tell them to watch your videos, EXCELLENT WORK my friend

[@gman13glpz]

Thank sir. You just saved me $100.00 for a specialist visit plus labor work. It was my High Limit switch. I just hit it with the back of a screw driver and it worked. Thank you so much, God bless!

[@texx2g3]

Just watched your video and five minutes later everything is fixed and working, you just saved me a ton of money by switching to KZbin😂😂 Awesome video and thank you so much!!

[@COCupid]

If you have a humidifier attached to your furnace your fan will keep running to maintain the desired humidity level. Learned that when we replaced our old furnace & upgraded our humidifier. You gave great info & explained it precisely.

[@kentcan]

I'd like to add one more! Well, it's really a variation of #8 (Shorted Wires), but my symptoms were not exactly as he described so I'll tell you what I discovered. I'm a home DIYer, and after watching this video I was still stuck, so I called my local HVAC guy. He helped me trouble-shoot over the phone, and here's what we found. CONDITIONS: All-electric furnace (heat pump) and a/c unit. Fan set on Auto, Thermostat control (Cool, Off, Heat) set on OFF! SYMPTOMS: Furnace blower came on in the middle of the night (freaky!). TESTS: Completed all of the tests in the video that pertain to my all-electric unit. I unplugged the motor wire from my control board so that I could listen to the relay switch without the fan actually turning on and off. Every time I flipped the shut-off breaker for the furnace I could hear the relay, so I knew my relay was opening and closing, but that meant it closed any time there was power to the board. So something was calling for power from the R wire. One by one, I started disconnecting wires from the control board until I discovered the Y wire (a/c cooling unit) was the culprit. Here's where I got stuck because I couldn't find anything online that mentioned this. So I called my HVAC guy and he said this meant my Y wire had shorted out somehow to the R wire or another source of power. He said this was probably at the outside unit and suggested it was likely either the Defrost Control Board or rodents. Yes....mice. :) RESULTS: So I went outside and pulled the cover off the a/c unit and--sure enough--there was a lovely large MOUSE NEST built in between all the wire connections! As I cleaned it out she scurried away...then I found the babies. I've got pictures--send me a message if you want to see them. :) So this explains the sudden fan activation in the middle of the night. Momma Mouse had chewed extensively on each of the wires, creating a massive mess. So I cleaned it out, plugged the mouse's access hole, stripped and reconnected all the wires, and I'm back in business!

[@doughairrell4048]

On my 25 year old Carrier, the Limit Roll-Out Switch was open. I unplugged one red wire and connected it to the other red wire and everything works perfectly. Ordering a new switch. The filter was clogged and we burn lots of white candles in the wintertime. The filter was the problem. Thank you for pointing out the candle use problem! Great video!!

[@barbarafields5785]

watched the video and then went and pulled the face cover off the recently installed honeywell digital thermostat and the incessantly running furnace fan stopped....i was able to reposition the errant {installed in the 90s} non green {blue} thermostat wire to the "G" lug and the furnace fan stopped immediately...works perfectly now...saved alot of time and frustration....Thanx

[@lennyphantom]

Tripped flame roll out switch was the cause of my fan continuously blowing. This video helped me out and educated me. Awesome job and thank you for your videos.

[@scarlett0464]

16:55 I just wanted to say thank you! After watching this video, I was able fix my unit by replacing the motor run capacitor for less than $9.00! I so appreciate you and the information you share.

[@la-gl4uh]

I wish you were in my city. I've had 2 different companies come out to solve the fan running problem. Neither of them did any of the troubleshooting that you described. Instead they said i need a new HVAC system to the tune of $7K . My system works fine heating and cooling except the fan keeps running. My system is well maintained, not rusty and worn out. I'm going to do your troubleshooting steps myself and will put the results here. I've already replaced the bad blowr fan motor myself and replaced the condensor fan motor myself. I know I can do this troubleshooting. Thanks. You're the greatest!

[@WordofAdviceTV]

Sorry to hear about the furnace.. Unfortunately there are plenty of companies that would rather sell you a new unit than fix your existing one.. Good luck with troubleshooting! Hopefully your culprit will be one of the 10 I list.

[@TimDyb]

ANY UPDATE???????

[@Holpopov]

My G wire and Red wire were not insulated and were close to each other but not touching. I insulated both and problem resolved. You saved me lots of money. It does not surprise me that you are willing to help others. I love Greek people and food!

[@MajestykMr]

Bad thermostat section seems to be our problem. When I remove it from the base the fans stops. Plug the thermostat back into it's base and the fan runs again. Will save us probably 500.00 here where I work. Thank you so much and you are an awesome tech.

[@ashleagale9398]

The screwdriver knock is all it took for mine! Thanks for sharing such invaluable advice!!! You have saved me a lot of money and time 😍

[@vedvern]

Thank you! Spent a couple of weeks trying to figure this out and your video helped me fix the problem!

[@paulgonzato2709]

Another to add to your list. I had a mid efficient furnace (Carrier) with the blower fan running all the time. Turned out there was a loss of power (power outage) and because the thermostat was calling for heat when the power came back on it the board wouldn't reset. I needed to turn off power to the furnace and then turn off the thermostat (lower temp) and then turn power back on and then raise thermostat. All worked.

[@Michael-tn4ir]

Thanks, man! I couldn't figure it out. Thought it was furnace control switch and changed it. Then I was going to change control board but checked the green and red first, like you said. Thank you again, and thank you Jesus! Saved me 300 bucks.

[@robertgarcia4117]

From Steve. I learned a lot from you. Thank you. I got my fan to stop. I took my thermostat cover off, I put it back on, and my fan stopped. Thanks 😊

[@douggys2]

Thank you saved me a lot of money, flame sensor ($8 Part) fix was very easy! There's a lot of people who can't do the fix were your business is needed.

[@bettybarnard1150]

Omg. I am a female and my fan was staying on the whole time and I've watch soooooo many videos and they only left me more confused..You on the other hand are such an awesome teacher I understood everything you said , You break it down to where your average Joe (in this case )your average Josie can understand..I will never watch another video unless it's yours..Thank you Thank you and Thank you again. Betty Lou

[@WordofAdviceTV]

I'm happy to hear that you found the video helpful! Thank you for leaving a comment like this. I try my best to talk "in English" so comments like yours reassure me that it's working. Good luck with the furnace and stay warm!

[@calebsmitherman4427]

I’m at the beginning of my career and I’m struggling with the service side of HVAC but I found this and I’m a book learner more than a hands on learner so this helps me Thanks guys

[@WordofAdviceTV]

Thanks for watching Caleb! Glad to hear the videos are helping. Good luck in your career! Only the first couple years are tough. After that it is only occasional tough jobs where there's a problem you haven't seen yet.

[@ltw1950]

I think this is a great video! Easy to understand and he is very personable, knowledgeable and knows what he's doing! Thanks for the help!

[@CaliforniaHobbiest]

Jay, you're a world class teacher! I wanted to share an experience you may want to mention in your reasons 7 and 8 regarding determining if the thermostat or shorting wires are the source of the fan running continuously. The footnote we would like to add is that when the diagnostics call for removing the thermostat cover from the wiring base on a NEST thermostat (and to our naive surprise) is that the wiring base is the thermostat on a NEST thermostat! (We took the Nest wiring base apart and that's when it hit me, it was loaded with PC chips and circuits instead of just contacts for the wires). We did all of the other diagnostics (thank you so much for the excellent video) just to be sure. We first isolated which 110v source from the ICM control board that was sending the power to the motor (fan, heat or cold...the cold circuit was the source of the power) by pulling the power wires to the motor off the circuit board one at a time. We disconnected all of the Low Voltage wires at the Nest wiring base (leaving the wires terminated at the ICM control board and the fan stopped running.... We replaced the NEST Thermostat and Base ... end of story. Thanks Jay!

[@larrybud]

Did you check the settings in the NEST as well? There's a "fan schedule" option which will turn on the fan automatically at preset intervals even though the heat/ac isn't running.

[@juliestewart5707]

Thank you. This was the most easy to understand explanation and direction for my blower that keeps blowing…I’ll have to see if I can fix it before my husband gets home!

[@venesatorres3055]

Thank you so much!!! You saved me a ton of money on a service call. My thermostat was bad, easy fix. Really appreciate that you posted this!

[@canzhu6326]

I love your lessons, the way you teach I understand. Excellent Job

[@mikesakellarides3463]

He diagnosed my problem at 3:56. A stuck limit switch which opened when I tapped on the panel with a flashlight. THANK YOU!

[@WordofAdviceTV]

I'm happy to hear you were able to get your furnace fixed quick! :) Thank you for leaving a comment, stay warm!

[@davidbillings3105]

Are you talking about a high limit switch that will not allow the heater to work? I've had limit switches go bad but the blower still worked amd shut off with no problem Of in heat mode it will not shut off because the house will not warm up so the thermostat can kill tje blower.

[@kevinwmorton]

Spent all day trying to figure this out. Bought a new thermostat and everything. Finally watched this video, went and gave the switch a tap and it worked. Thank you

[@TrongNguyen-ky6wy]

I’ve narrowed down to the relay board, and unplugged and reseated the connections and it worked to stop the fan from remaining on. But after turning heat on and then off, the blower fan resumed its problem again :( . The only way to get the fan to operate normally is in heater mode which it will shut off automatically after temperature is reached. Any insights will be appreciated.

[@ezdoesit20]

Super informational video... I have one for you. Everything was running perfectly. Fan turns on and off with the ac or heat. This was with the original emerson thermostat. I installed a nest. I connected common wire to board in the unit. I hooked everything up as the manual said. And now the nest will not control the fan. The fan runs constantly. Everything else works. I then removed the nest and re installed the old thermostat and everything was good again. Any ideas?

[@jacklucas7265]

I am writing to say thank you for your video. I recently purchased a home which had new HVAC installed. The front bedrooms were the longest run from the from the air handler and the rooms were warm in summer. The HVAC service people I hired corrected the ducts to supply more air to the bedrooms but the a/c or furnace didn't run long enough to make that much of a difference. The thermostat was near the rooms with the shortest duct runs and so when that area was sufficiently cooled or heated the system shut down. I concluded the thermostat had to be moved to the area that was under served. I moved the thermostat and rewired and then the fan wouldn't shut off and the furnace never came on. I rechecked my work and it was ok, but I noticed a red led on the circuit board inside the air handler was flashing so I knew there was a fault somewhere. I resigned myself to calling for service in the morning and as last consideration I went to KZbin in search of a potential solution. When you mentioned a blown fuse I remembered there was one there but I thought blown fuses would shut down the motor and so didn't inspect it. I went back up into the attic and pulled the fuse and sure enough the fuse had blown. I replaced the fuse and everything works perfectly and the temperature in the front bedrooms is in line with the setting on the thermostat. You saved me the expense of a service call and probably a lot of money. Once again thank you, in my opinion you have earned your place in heaven!

[@WordofAdviceTV]

You're welcome! I am happy to hear you were able to track down the problem and get it fixed yourself! Thank you for leaving a detailed positive comment, stay warm!

[@gamewizardks]

Great video. Ran into a fan relay on an electric furnace that was sticking and I replaced it. That call made me interested in watching some videos on the subject. Thanks again for the great content! You and AC Service Tech are my favorite service channels!

[@christopherbrennan6223]

So I was surfing the net trying to figure out why my ac air handler wasn't shutting off when set temperature was reached. My searches came up with a multitude reasons and I became increasingly concerned over which component(s) could possibly be the cause. Well I came across your video, and the first cause you mentioned was the actual problem. Thank you so much for posting your your super helpful how-to video!

[@larryrh2]

Very clear and concise - Excellent! One of the. Best fix it videos I’ve ever watched. You certainly know your business and I’m sure your business must be very busy.

[@jamest3503]

Asking my tenant about number one saved me the trip. Ty.

[@arthurjackson5430]

Very informative video explained very simply- even to those with no knowledge of the topic...(quick, precise, and actually kinda entertaining!) I was able to fix my problem with your help just a few minutes in! Keep up the good work!

[@nrraab]

Great video! House was getting down toward 60 degrees and was wondering if we would have heat tonight. Found out my rollout switch was tripped. It's working now. tomorrow I will check the intake and exhaust, but the key is we aren't going to suffer tonight. Thank you!

[@renenunez1254]

Dude....you are just the "fix" I needed today....nice accent and awesome haircut..and all that comes with ac/heating knowledge!

[@pigbelly100]

You sir are awesome!!!! I haven’t had heat the last couple days here in upstate New York, where the temperature has been 7F degrees during the day. From the beginning, I thought it was the high limit switch but couldn’t find it. Thanks to your video showing it, I tapped on it with a screwdriver and now it works! Thank you 🙏

[@hdalebeggs8786]

This guy is very articulate. This is the best video I have seen!!!

[@saldore6884]

Thank you. The way you explain n speak n show makes everything so easier. Blessd. Other people charge aloud just to diagnose. You make it free n allow us to know and do our selfs. THANK YOU SO MUCH. THANK YOU FROM MY FAMILY KODS N WIFE FOR THESE VIDEOS. Just to note : had some diagnose n conclude it was the board. Yes worked right after. But the bill was over $1200 bucks. So thank you again. DYS STYLE. BLESSED

[@jayhvac4474]

Had this same call today but it was a heat pump.... after troubleshooting the system I found the new T-Stat that was installed by the home owner was faulty...with the thermostat fan set to auto and the system set to off I still had continuity going from R to G, after replacing the T-stat everything worked as usual. Thanks for the video man

[@WordofAdviceTV]

Glad to hear you were able to track down and fix the problem! Thank you for watching and leaving a comment!

[@tonyseran7930]

I started to go through the possibilities one by one. But what did the trick was the gurgling when the fan kicked on. I was getting an F5 error (Continuous Fan) on a Goodman furnace. After draining the gurgling water from the fan shroud, and beating on the high limit switch I was back in business. Most excellent video. Thank you very much.

[@robertdean6222]

Very informative and knowledgeable. Your dad’s right you do you use your hands a lot but that’s OK you’re explaining things better than anyone else on this channel ! Subscribed and smashed the lake button every time I watch

[@roseedbartok1757]

Fantastic! So easy to follow and understand, I ohmed out the green and red wires and discovered I had connected both the thermostat and A/C wires together. Thanks so much, your videos on central A/C have also been a huge help to me (and my neighbors, saving us big $$).

[@MrSticks9999]

ohmed out?? LOL

[@roseedbartok1757]

@@MrSticks9999 a holdover from 20 years in the USAF (ground radio maintenance)

[@MrSticks9999]

@@roseedbartok1757 Doesn't make it correct. You are measuring resistance. Ohm's is a noun, not a verb. You don't "horsepower out" an engine . .you increase the horsepower.

[@dhsfb51]

Good info! My blower hasn’t been running constantly, but it comes on every 30 minutes or so and runs for like 15 minutes at a time. The setting is on auto on the thermostat. Had a company come out today to service it and I told him about the blower, said he couldn’t diagnose it until it came on, and of course it didn’t when he was here

[@tinawillis5128]

My limit switch was not working but after i purchased and installed a new one it was doing the same thing. I checked all the other reasons that you had listed but still same issue. Finally i took my meter and found that one of the wires from the board to the limit switch was bad at the (what looked like a fused end before the terminal connector) i cut that out installed terminal connector and it was fixed. Thank you for putting me on the right track, great videos.

[@richardmccomb3938]

Woke up the other morning to find my furnace blower motor running Non-Stop found your video I tested the flame roll out switch and then after I checked the high limit switch and plugged it back in the fan stopped running everything works fine, so I have a new one on its way and I'll replace it when it gets here thanks for your great videos.

[@bettyfletcher3738]

THANKS! I did get my unit to start turning off THANKS to your easy to follow instructions. Money saved💃🏿👏🏿

[@daniello8592]

Some people have the talents to make others to understand things easily, you Sir are one of them, I wish all of my college professors were like you! BTW my problem was the reason #9, and I fixed it by smacking the fan relay with a screw driver, thank you!

[@gonnadanceagain]

Getting ready to try some of what I've learned. You are a very good teacher.

[@lyledouglas8324]

This guy is the best Solved my problem with the first 4 answers. Probably tapping limit switch, or the flame roll out reset button solved my issues.

[@lausy3]

You are super awesome. This video helped fix my blower that was not turning off. It turned out to the be the high limit switch. I had to take it out and whack it few times. That unstuck the switch. For others and more information for when this happens with furnace that only has R and W wires. I got fooled into thinking that the control board was bad. I replaced the control board and had the same problem. What happened on the control board is when the high limit switch trips, 24V is applied to the W wire. This caused my Nest thermostat to think that there is no power coming form the furnace. This wasted 3 days of mine trying to figure out what else could be wrong. After the high limit switch was reset, the W wire had either 0 volts or a very low voltage so the Nest thermostat can be powered on.

[@dbo666]

High limit switch hit with a screwdriver and I’m back up and running, great video thank you!

[@titan2425]

Thank you for your very informative video. I changed the batteries for my thermostat and the fan kept blowing; since I always leave my fan switch on auto I did not think of checking it until I watched your video. The other videos I saw never mentioned to check the fan switch. You saved me a call to a technician👍

[@litzdog911]

My daughter's furnace presented with this exact symptom. When calling for heat, the blower motor would continually run but nothing else was working. It's a Payne furnace and flashed error codes 33 and 13. I discovered that the inducer fan was not running at all. It was getting 95 VAC which wasn't right. Should be 120 VAC. Discovered a slightly caked/cracked black wire between the control board and the inducer motor. Fixed that wire and all was good. I'm guessing that wire was too close to something hot, causing the insulation to degrade and the wire to open up. I would never have guessed it would be a wire! Your troubleshooting tips really helped, saving my daughter hundreds of dollars! Thank you!

[@shawnmurphy282]

Tapped the limit switch and heat is working ! WOOT ! Saved an assload of $$$$. THANK YOU.

[@Chow_Yun_Matt]

Thank you so much for this, you just saved me a service call! My issue turned out to be the 3A fuse on my control board. So far, it has not popped again, so hoping I don't have to chase a short. Great video!

[@christinacoulter9689]

Awesome! You saved us at 6:39 with the flame rollout switch needing to be reset. Thank you!!

[@rudygarcia7477]

FOR ONE THANK YOU SO MUCH FOR TAKING THE TIME TO HELP WE DO IT YOURSELFERS TO DIAGNOSE THESE PROBLEMS THE VIDEO IS WELL APPRECIATED I PERSONALLY RAN ALL THE TEST AND CONCLUDED THAT THE ON-COMMAND COMPUTER BOARD IS BAD OR THE RELAY THAT CONTROLS THE FAN BLOWER RELAY IS IN A STUCK MODE NOT ALLOWING THE FAN BLOWER TO TURN OFF WHEN IT SHOULD IN AUTO THE RELAY IS SOLDERED TO THE CONTROL COMMAND BOARD SO IT IS PROBABLY EASIER TO REPLACE THE ON-COMMAND COMPUTER BOARD TO SAVE THE HASSLE THANKS SO MUCH!!!!!!!!!!

[@llibressal]

Awesome, you just saved me a $100 service call. I metered continuity on the high limit switch (also had a code 13) and I had no continuity. To confirm I jumped the both of the HL wires together and walah, operation normal. Will replace the switch asap.

[@robertgarcia7377]

God bless you man! Great video, I have my fan running all the time, maybe the thermostat is bad , I will check that tomorrow, 33 degree outside.✌🏻

[@CrisisGuildWOW]

This guy is the best. My problem was with the high limit switch. The internals of the switch were fine, problem was both of the spade connectors on the back where the 2 wires plugged in were so badly oxidized that I had no continuity between them even tho the switch was in the closed position. A wire brush was not enough to clean the contacts, I had to use a wet stone and by hand grind it down until they were shiny again. Never seen buildup like that before. Furnace is 22 y/o and I believe the switch and wiring are original....

[@dmitripogosian5084]

That usually not how you should clean the contacts, mechanical grinding grinds off the plating on the contacts. You should soak them in vinegar and gently clean after.

[@deli3639]

Really appreciate the detailed information and the attention to detail provided in this video. I wish I have more info on how to hire him. Good luck man your workmanship will take you places.

[@winstonsmith6927]

He solved my problem with the comment about the cut off on the fan and limit controller on an old furnace. I had set this temperature low for efficiency, not realizing the temperature inside the furnace could stay at that temperature even after the gas was off for some time. I have been looking on the internet and found only 3 or 4 standard answers to this question.

[@blinks0187]

Thank you for this video, I was about to buy a new furnace, I just had to reset the flame switch, you saved me a lot of money 💰 😅.

[@andyfashant4677]

Fantastic help Jay! I also had a struck high limit switch and the wacking did the trick!!! Many thanks from a cold spring evening in Minnesota.

[@khusanazlarov990]

As usually you are ROCK! Pls keep doing it, you helping a lot of ppl. God blesses you and your family

[@WordofAdviceTV]

Thank you! Glad to hear the videos are helpful! God bless you and family as well!

[@lylethielen5479]

great video ! you got me to fix my continually running fan today ! checked everything in order of the video, and it was ( i'm guessing ) a stuck "K3" realy on the PCB . a few taps and now the fan isn't running all the time . as an auto mechanic i am around tons of relays and i know i am living on borrowed time , but you saved me a service call toady ! THANKS !

[@kyle998cc]

Thank you! I pressed the flame rollout switch button reset and the furnace worked properly again.

[@WordofAdviceTV]

You're welcome! If the flamerollout switch trips again I would suggest watching my flamerollout video as something more serious may be going on. (Such as a cracked heat exchanger)

[@lesterwesner6977]

Your a good teacher. Explains very well.

[@donwood9542]

Great video. Very helpful. I went thru video step by step and it turned out the relay on the control board was sticking. Problem solved. Thanks

[@myutubehandle47]

Smart and charismatic, a people person with good teaching skills!

[@RRaucina]

I knew all that but after 20 years of little hvac work this is a great refresher. Well said - you must piss off some hvac guys because their $200 service call for a $3 limit switch just went away! As for a gas furnace not starting, or failing to ignite, the fan air switch has brought me a lot of calls. Loose hose, blocked passage. Sometimes your hammer trick works there too.

[@WordofAdviceTV]

Glad I could refresh your memories! :) I agree, many of the most common fixes are actually very simple. Thank you for watching and commenting!

[@TaffenFelspar]

This guys makes the Best HVAC Videos I've seen!! Thanks!

[@We4winds]

What a helpful video with easy to follow instruction, illustration. The expert here is so easy to listen and follow. Thank you!

[@yzBLASTER]

Thank you very much! Your video helped me fix my heater, now my house is nice and warm!!!

[@bigstepper2235]

Another reason could be the limit could be actually touching the heat exchange, probably not but possible. Love your videos man i learn a lot from you

[@FerretPD]

Extremely comprehensive and informative...Thank you!

[@pennyuyitung4854]

Much appreciated on the tips - Very helpful and well explained on the possible things to check. I know you said the reasons were not in order - but if you were ever to edit/re-shoot - do the codes first before the other checks. btw - enjoyed your talk in the end. Your presentation is good.

[@starrnumberone]

Thank you so much for your video. I found what MY issue was within the first minute of your instruction. I live in a very old building and my thermostat dial is the old fashioned round dial. One day I went to turn the heat down and I must have hit the auto fan to on with my pinky finger by accident. It was driving me crazy figuring out what had happened so quickly that would have made the fan continuously blow. The worse part is that the auto fan is on the far right of the dial and the heat and cool is on the left. So in the beginning, I figured that's what I might have done, but forgot to look on the right of the dial. What a dummy!!! LOL Thanks again for your help!!!