A Simple Trick To See If Your Heat Exchanger Is Cracked.

[@binscamd7497]

You should show how the burners look while running with the hole in the heat exchanger

[@InternetDude]

We need more honest folks like you!!!

[@RealFuzzyPickLE530]

He has good intentions, but his advice is dangerously ignorant. He portrays a cracked heat exchanger as a minor issue, and likely a scam. People die every year from cracked exchangers, and many more suffer irreperable damage from CO poisoning. This is a neat trick, and we use similar observations during testing, but you need a combustion analysis and a CO report to know for sure. Be wary of this guys advice on this matter.

[@masterdirk101]

"honest folks" don't tell people cracks in their heat exchanger are fine if they are small. Small cracks get bigger when the heat exchanger heats up and causes metal to expand.

[@percyfaith11]

@@masterdirk101 How do "honest folks" know that the heat exchanger has small cracks if they don't take it completely out of the furnace and inspect it? They can't. They just make up false tales about cracked heat exchangers to sell expensive new systems.

[@Watchyn_Yarwood]

Amen!

[@masterdirk101]

@@percyfaith11 The same way techs do, by inspecting it in place with a couple of cameras or mirrors? I've never condemned a heat exchanger for a crack that the homeowner themselves couldn't also verify. I also take videos starting with looking at the furnace itself which cuts all doubt. that its just some saved picture. Either way, this is a poor test to determine a heat exchangers integrity, as I've said the small cracks expand when the heat is on, so a test on a cold heat exchanger might not say much. Even immediately after cool down. I give credit to his point, people are out there trying to scam you and get you to buy a new system, its a fact of life, the problem is people are going to do this test and think their furnace is safe to run while they have a CO monitor from the early 2000's plugged into an outlet somewhere.

[@jim9337]

As a former gas fitter I was glad to see you putting out good info so folks don't get scammed.

[@tedevans2095]

As a Senior appliance technician, I just gained valuable knowledge that will be very helpful for me. This young man takes his work seriously. I wish that there were more people like him. Thank you 😊

[@patrickmccuiston7762]

25 Years in the trade here, your video is everything a technician needs to know. Well Done.😊

[@stevenmachnick9613]

You need to be retrained

[@74ace468]

I use an incense stick for all kinds of similar draft and air leakage tests. Works great lasts a long time.

[@edlauren9434]

Outstanding explanation!!!!! Thank you man! I am a licensed hvac/refrigeration contractor. Will be sending this video to my customers! It’s the best and easy to understand video about heat exchanger issues that I’ve seen! Thank you!

[@garmin1488]

Great video, thanks. My furnace is 27 years old still working fine. I've replaced the igniter and the inducer motor twice. I have a new furnace sitting ready to go , bought it 5 yrs ago waiting for this one to go. lol bought it for $1250 Canadian they've doubled in price since then.

[@wilsongonzalez8753]

Well explained and well done. You should it be a teacher because you take the time and I can see your devotion. Keep up the good work. Professor WG, US Army Retired/Disabled Veteran from Pennsylvania.

[@UQRXD]

Correct me if wrong. But you did test on a cold heat exchanger. Small cracks some times seal when cold and expand when hot. Always have detectors. More than 1 they can fail too. Life is priceless. In fact the furnace should be interfaced with one to shut it down. But manufacture liability may be to much for that. I am always amazed that homes with gas lines don't have auto shut offs with a gas fume sensor. Many an explosion could be avoided. After all the electrical system has fuses and breakers.🧐

[@danielstrother2494]

You are absolutely correct. They often don’t “roll out” until warmed up

[@AnotherRandomComment]

This guy means well but is a little “underinformed” and is trying to make Hvac guys looks shady. 90% of heat exchanger cracks don’t show up unless it has gotten very hot.

[@garynicholls72]

Hi Gary from the UK I am an old heating engineer and I haven't worked on hot air systems too much, just wanted to say Great video very interesting and informative keep them coming Very good tip thank you

[@davidgleatham9966]

good follow through . watching the match burn fair after going back to an undamaged tube offers a very positive test. watching both flame sources got even better. i did hvac for many a year and never new of this test. great way to upcycle an old furnace- the leak demo

[@rayzerot]

Even easier- run the blower and stick your manometer in each tube. Any pressure change indicates airflow from your blower into your heat exchanger and proves there is a crack (of any size)

[@6paxer]

How many homeowners have a manometer. You missed the point of this video.

[@ralphcarpentieri]

thank you my friend, as one who has been in the industry for over 25 years it's refreshing to see such straightforward honest troubleshooting and a better technique than cutting into the plenum for visual inspection. I'll be incorporating this technique in all off my service clean and tunes to insure clients are not taken advantage of, it's unscrupulous business practices like those which gives our profession a bad name ,thank you sir!

[@Ratlins9]

I got ripped when my my ac unit developed a leak and was told it just needed to be recharged. I vowed to educate myself to not let that happen again. Thank you for your educational videos.

[@primusheating1]

It's just like a car tire losing air consistently. You have a leak in that tire. The same goes for leaking refrigerant.

[@Ratlins9]

@@primusheating1 Thanks primusheating1, being ignorant, I took the technician at his word until a few months later the same problem occurred. This time I researched it only to find out refrigerant doesn’t go bad but can leak. Called another company who quickly determined it was a leak. Appreciate your comment.

[@paulrozinski1488]

The same happened to me about 10 years ago. The thief charged me $10 PER OUNCE and put in almost 6 POUNDS of R410A . Never again !!! Knowledge IS power.

[@tg-bh2up]

How did you get ripped? was the leak large enough that you think the A coil, refrigerant lines, or entire unit should have been replaced and you now will be constantly recharging until then? Or is the leak rate small enough that it might be several years before needing a refrigerant top off?

[@joeschleprock3409]

Same thing happened to me.Buhler Mechanical in thunder bay ripped me off.

[@doncollins786]

Old HVAC guy here, video was very well done!

[@richtech22602]

It might be worth noting that this should be checked with both a “hot” and “cold” exchanger as sometimes if there is a crack in it, once the exchanger warms up, the metal expands slightly.

[@kennethkline7702]

Do you actually know what you're talking about? Or are you just saying this as a concept?

[@JesusSaves71185]

@@kennethkline7702he actually knows what he’s talking about. It’s simple physics. Use google next time before posting a comment.

[@raccoon874]

*All three commenters above have IDs that end in 02. Strange.*

[@KennethCherisol]

​@@raccoon874 Possible bot activity or someone in Desperate need of attention. Lol

[@topher8634]

It's a conspiracy.

[@LottimusMaximus]

This is a great way to do this. I usually use a combustion analyzer, but it’s hard to explain to customers there’s a problem. This helps visually.

[@urielvargas6777]

Man you are my hero, replaced my furnace following your tutorials, I am responsible for my actions but very thankful for all the info you share. -replaced. -built plenum (the old one was taller and slimmer) to connect to Acoil boxing. -tested gas pressure with the amazon white manometer you used in one video. -verified for days that carbon monoxide does not exist. With the klein tools that you use. All for less than 700 including flexible gas line, new gas valve, new filter. New furnace was 3 years old but never installed, I got it for 400. Cleaned it and it runs perfectly.

[@diyhvacguy]

Amazing. Thanks for sharing!!

[@RealFuzzyPickLE530]

​@@diyhvacguyYou need to educate yourself about this subject before posting videos online that could actually get people killed. This is dangerously ignorant.

[@natersalad889]

​@fuzzypickle5307 it doesn't take a doctorate degree to work on hvac equipment safely and correctly....

[@urielvargas6777]

@@RealFuzzyPickLE530 with all due respect he doesn’t tell anyone to do it. He shows how it is done, we are adults who understand the risks, and also follow thw safety tips and advice from @diyhvacguy. So all cool sr.

[@troyroads8058]

Did you install the flex line into the furnace with a drip leg against icm code like this video?

[@vernonlemoignan1392]

Great video. I have an 26 year old furnace in my home and plan on using it forever if possible. The new ones are expensive junk. I have a complete identical furnace for parts that worked fine when “upgraded “ a few years ago from a neighbor. I have co monitors but this test will help me make sure the old beast is still safe. Thanks!

[@jonswisher8796]

This is one way that MAY tell if you have a bad heat exchanger, but it only works if the hole is close enough to the flame to make it move. Certainly not the best way to tell. If you have an old furnace just get a cheap inspection camera and look at the heat exchanger. Easy, or follow safety advice from a rookie HVAC guy that retells stories he heard on the internet. Good luck, and yes, there is expensive junk out there but there is some very good equipment that will make your home much more comfortable than on old one ever could and will last a good 20 years if installed orrectly, but that’s not important to some people, so keep the old one going. I agree with that.

[@chetmyers7041]

@@jonswisher8796 My rental property has a Trane updraft furnace installed in 1990 that is still going strong, and on the original ignitor and draft motor.

[@jonswisher8796]

@@chetmyers7041 I just updated the old gas train on a 1954 Ward gravity because the elderly homeowner likes the heat and no fan. If it is installed correctly and maintained, most equipment can last a long time, if not, it will not last. Trane make s a good product, we work on them all.

[@Michael-uj4zw]

Great demo, great service to the public! I was a heating/cooling guy for several years and we used to use smoke bombs which would cause a sulfur smell in the home immediately; this is much easier! Thanks again!

[@rayzerot]

Even easier- run the blower and stick your manometer in each tube. Any pressure change indicates airflow from your blower into your heat exchanger and proves there is a crack (of any size)

[@stevefifield1207]

Sure - but this was a simple test for homeowners, not needing any other tools than a match.@@rayzerot

[@lisanelson4750]

Thank you for putting up this video! I was nearly scammed years ago by an HVAC guy who told me my furnace had a cracked heat exchanger. Even whipped out his "carbon monoxide detector" to show me the high numbers coming thru the vents. I asked him then why my multiple CO monitors all over in the house were not going off if there was life threatening levels - to which he shrugged off. Then he and his boss tried to pressure me into buying some off brand furnace replacement. Fortunately I had to get to work at the time, so put him off until I had a chance to arrange the finances. I then got a recommendation from a friend at work for a different HVAC guy to come out and look at it. He found that not only was there NOT a cracked exchanger, but that the previous HVAC guy had "booby trapped" my furnace by manually destroying the computer board so the furnace would not run at all now. The cost of replacing the computer board on the old girl was almost as much as a new furnace, so I had the new HVAC company replace it with a well known brand. Now I understand it better and will know how to check myself! Thanks!!

[@Jon-hx7pe]

co alarms have a high cut-off, not displaying anything below 30ppm. no co in doesn't mean heat exchanger isn't cracked.

[@lisanelson4750]

@@Jon-hx7pe The numbers he was showing me were all over 500 - well above the the cut-off and a life threatening situation - if true. The second HVAC guy who found the damaged computer board took multiple CO readings at the air vents - all were 0. People should ALWAYS get a HVAC second opinion when any repairman tells them the heat exchanger is cracked or leaking. CO is nothing to mess with!

[@Jon-hx7pe]

It is very possible that someone was trying to scam you. At the same time, people need to understand no co at vents does not mean the heat exchanger is fine. Only visual inspection can for sure confirm the heat exchanger has no cracks, holes, popped crimp rings. A combustion test including oxygen can tell if the heat exchanger is leaking badly, but can have a normal combustion test but it is still cracked. When a defect is found, the tech should be able to show it - second opinion not needed. if you have unsafe wiring, it is still unsafe whether or not the wiring is actively overheating and smoking. This guy's channel is terrible and he's basically trying to make it out like every hvac tech is an scam artist and there is nothing to this field, anyone can do it. Telling people to only buy crappy single stage mid efficiency furnaces too. There's some great stuff on youtube but not on this channel. @@lisanelson4750

[@danielstrother2494]

I absolutely despise people like this. I’ve been doing it 24 years and about a year ago I found out the guy I was working for was doing this. He would already have the change outs set up a lot of the times. The way I found out was that a guy had a 90% furnace and I was told just swap it out. He said it had a bad heat exchanger…”easy swap out use the old venting. As I was finishing up and about to attach the venting…I noticed the drain on the intake.??? I had my helper go outside and make sure the venting was ok. The exhaust went out 90 down then back up 2’ leaving a trap In the exhaust. The intake was piped up 2’ higher than the exhaust!!! I told the customer we have to change that and I’m not sure how it ever ran once the trap was filled with water…he then told me he had to drill a hole in the bottom of the trap! 🤦🏻‍♂️. So come to find out it was going out on a pressure switch code….no sh*t it was especially when the customers trap was sitting in a puddle when the rain was heavy. He then called a meeting in the morning bitching because he never quoted that job for new venting!! I lost my shit and walked out of his meeting. So later that day my apprentice told me that an ac we changed a few weeks back only had a bad capacitor…he told an old lady her compressor was bad….we parted ways after that and I went back on my own. What an ahole!

[@terrymeyer]

This is being done on a cold heat exchanger. A crack on a cold heat exchanger can be closed or sealed up but open up after it has been warmed up.Not saying this is a bad test just not a perfect test. If you have a bigger crack it will work real well., if it a smaller Crack that opens up more after it is warmed up it might not work as well.

[@s.j.5850]

You can do the same test after having warmed up the heat-exchanger.

[@TheTruth10132]

You are the best, fantastic explanation. I have seen HVAC companies are some of if not the worse on scamming consumers and not just cracks in the heat exchanger, but trying to sell a whole furnace because a fan going out (very easy to replace) or igniter, etc. Thanks again.

[@videos10]

This was a good demonstration, im a tech, and never knew the lighter technique.. your channel has GROWN TREMENDOUSLY! And in such a short period of time as well! Bravo!

[@diyhvacguy]

Thanks so much. It’s all because of awesome viewers like you! 🤘🏼🤘🏼 thanks for your support

[@troyroads8058]

Could you imagine explaining to the judge that your not guilty of neglegent homicide of a family of 5 cause you used the "matches trick" you saw on you tube to ensure everyones safety......

[@predatorishi]

My friend is HVAC contractor for commercial hospital buildings and I have been discussing HVAC troubleshooting since years though I am a software engineer, this information is sooo accurate! Thanks.

[@jrc2905]

Excellant tip, my thinking is that the simplist way is almost always the best way. You just earned a subscribe.

[@larry6536]

Thank you. I wish there were more honest folks like you.

[@PB-bb3di]

EXCELLENT TEST , Perfect clear explanation of furnace heat exchanger and testing. The video is the best I have ever seen about furnace sequence of operation and proving crack with matches. Thank You!

[@natersalad889]

Great idea.... also having the ductwork attached on top of that furnace would add a little backpressure to help make the flames reaction increase with that slightly higher pressure coming in on a blower system thats not totally unrestricted at all

[@Lenny8679205]

I bet if he put a piece of plywood on top you would really a reaction.

[@RWMorgan39]

In the house, close all the supply's as good as possible to build up pressure

[@willrefling6395]

Just saying, you don't actually have to build pressure for this to work. In most cases the flow through the coil is going to hit a reduced cross section. So you have an increased velocity. This will create lower static pressure than ambient. Which will still cause the flame to flutter. for example induced flues on old water heater. The density change from combustion flows up to an open air hood above the water heater. That high velocitiy creates a low static pressure zone which induces air flow from the room to carry the combustion products and the air from the room up the stack. Another example of this principle is fluid injectors.

[@s.j.5850]

@@willrefling6395 Sounds like an engineer's perspective. Appreciate the technical explanation.

[@donhauff4586]

Thanks for the tip. FYI - the 1998 date you pointed out is not the date of manufacturer. The date of manufacturer is the first four digits of the serial number in format MMYY. The 1998 date you pointed to is the date of the applicable code referenced there.

[@madmax8620]

My first four are 9104..... So what month is "91" exactly then??! (MMYY, according to you) Thanks Btw... it looks way older than from year 2004, looks like its from early 90s

[@MiguelRdgz916]

​@madmax8620 there are a few manufacturers that label their serial number different than the rest. I'm going to guess that you have a goodman or an amana system. So yours would be first 2 digits are the year then 3rd and 4th digits are the week that the system was manufactured

[@madmax8620]

@MiguelRdgz916 its a janitrol, and that would make sense, what you said. We (with the repair man) are having a real hard time figuring out why it is malfunctioning, and only short cycling. This is what we (he) did; Checked for flame rollout and flame tested for cracks in heat exchanger. Tested good. Cleaned the ignitor and flame sensor. Then Replaced Ignition board that allowed the flame sensor to be bypassed, and allowed the ignitor to be the sensor instead(a dual option sensor board ?)...THIS made the Furnace operate correctly, so we thougt the flame sensor was bad, and ordered a new replacement sensor. The repair man wanted his expensive board back, as it was a temporary loaner until the new flame sensor arrived. Installed the new sensor, wired the board appropriately, BUT THEN it continued to malfunction like before, intermittently ignighting, and or short cycling(with new board and sensor). Voltage/resistance tests were performed, but could not identify the problem. Any suggestions would be quite helpful at this point, as the repairman (a friend) is stumped now....???

[@MiguelRdgz916]

@@madmax8620 does the igniter come on? At what stage of startup is it short cycling

[@MiguelRdgz916]

@@madmax8620 oh and janitrol is made by goodman. It's almost like I know what I'm talking about 😂

[@mptr1783]

My man, thank you very much. Im about to replace the gasket on my Goodman collector box cover which is leaking. I want to make sure the exchanger isnt damaged and will do this test first. Again, thank you very much!

[@davkenrem]

I think I just got, got by an HVAC contractor for a cracked heat exchanger. I kept the old furnace and I am gonna do this test. Wish I,d seen this last week.

[@DoubleNDonn]

DTE (Detroit's Utility provider) came out to fix my furnace and ended up tagging it and locking it out because they said the heat exchanger was cracked. The furnace was over 30 years old so I just replaced it, luckily my neighbor used to install furnaces for DTE and replaced it at cost + a case of beer, my help and I donated to his grand daughters college fund😉

[@mikeoneal3550]

Great demo, great service to the public! I'm a heating/cooling guy for several years and this is much easier than taking everything apart. Thanks again!

[@Edmonton98]

2 months of searching for this information!!! THANK YOU!!!!

[@drozcompany4132]

Man that was a tiny hole. Wouldn't have thought that little of a hole would move the flame so much! Very informative!

[@RepublicanJonCardiasmenos]

I’m a former facilities maintenance Director that got into the HVAC trade and our collecting necessary tools to do proper furnace inspections in residential homes. I was very grateful to see this video and are on my way to Home Depot to pick up the lighter that you used so I can add that to my furnace inspections. Thank you very much and God bless you for spreading your knowledge. Jon-

[@geoffap0]

Thank you, thank you, thank you! I hope more people find your videos! Stop the Ripoffs! You should be on Clark Howard’s show.

[@Icantfindtheanykey]

Great vid. Honest. Truthful. Helpful and simple. Thanks for educating us. Keep up the great work.

[@miketallman171]

Very helpful hard to find honest people willing to help you not to get beat education is powerful even now someone comes to my home I will ask them to show me how he determined my heat exchanger was bad kudos to you my man kudos thanks

[@tgriebe]

Great simple test. I have an older Carrier with the secondary heat exchanger issues and this is an easy test to make sure it is not leaking.

[@RealFuzzyPickLE530]

This is not a conclusive test. You will need a combustion analysis and CO report to determine if there is a crack or not. If it is leaking and you miss it, it could kill you and your loved ones.

[@james6794]

If you have a newer system with cooling I'd recommend pulling the disconnect for the condenser and putting it in cooling mode. some systems wont run the blower at full speed when only calling for fan. calling for cooling with the disconnect for the condenser pulled will give you full fan speed

[@diyhvacguy]

Great idea. Thanks for your input!

[@MrDmadness]

Ive used this method before. Its a good way to show a customer the issue

[@s.j.5850]

Great tip for checking for cracks/holes in the heat exchanger. It's a lot cheaper than an analyzer! This one I will pass on to my HVAC instructor.

[@Tonyhvac]

I appreciate this class brother,happy 2024 👍🏽💯

[@bsintzel]

Information is power. This info may save my bacon one day, so I'll add it to my tool chest. Much appreciated :)

[@mikesaldamarco5193]

Outstanding video. Thank you! I am dealing with this issue right now. Flames unstable. Trips flame rollout switch after 10 minutes. Just installed new inducer thinking it wasn't doing exhaust sufficiently but flame rollout switch still tripping. Tech verified temp on switch exceeding tolerance. Concluded must be working correctly. More strange is that no exhaust from inducer. Tech now believes it's the heat exchanger. Welcome comments from anyone who reads this.

[@chetmyers7041]

Just curious what the problem was with your furnace?

[@mikesaldamarco5193]

Burners would shut off after 10 minutes of operation and trip the flame rollout switch. Contractor recommended new furnace stating Heat exchange is cracked. I have since discovered my secondary heat exchanger is clogged/rusted. However learned today that and both primary and secondary heat exchanger are still under Carrier warranty and they will replace. @@chetmyers7041

[@kmbawdry]

yup, I feel like I was 100% scammed last year. Wish I knew this info back then or at least had the idea to look into the claim that we had a cracked heat exchanger. Really appreciate the honest information you're providing here. Thank you DYI HVAC GUY 🙏

[@Mike-Olds-1]

If my furnace wasn’t having any issues I would have kept it. The way so many things today are made a upgrade can just as easily be a downgrade

[@gnic76]

That is how I see it as well, which is why I still have a 25 year old furnace that works fine. Plus an upgrade is a lot of $$$.

[@natersalad889]

Barely call it an upgrade, just newer equipment. Newer isn't always better, keep what you have

[@fatt-shirtprinter3394]

All these replies are wrong nee units are just way more efficient. I’ve even seen electricity bills lower after upgrading

[@joemartinez9836]

Gas is cheap. Last months gas bill was 14 bucks​@@fatt-shirtprinter3394

[@arth.4196]

Thank you. It shows that Your Business Model is working. Much success.

[@maxwellsmart3156]

Excellent video, very thorough, and it's burned into my memory without any flickering. Knowledge is power and thanks for passing it on.

[@dcairns61]

Great tip for a DIY check. I am very impressed on your one handed match lighting skills :D

[@reaksmeymaranda2341]

This is unbelievable knowledge you’ve shared with us. Thank you.

[@j.markrauf6738]

Thanks!

[@munozinni]

Hola señor DYI I was watching the video I just found today and I will watch the next videos that you recommended to watch after this one it’s amazing the knowledge that you have and the experience you have achieved working with hvac systems I will go to school in the future and I will enroll in this hvac 😊Saludos from Texas 👋😃👋you have a great day 😊

[@donc.8019]

I thought about that.with this video I know what to look for now. My issue is a blue flame with yellow Ridge. I did Match test it looks good. Burners are all clean. Did match with induction motor on also I get a little Backdraft feel something may be restricting induction motor draw also I feel my gas pressure may be low (will have professionally check) Thank you for the video

[@jimt7851]

Brilliant video young Sir! One of the best videos on the subject. Thank you for taking the time to explain and show exactly the issue and what to look for. Keep them coming. Much appreciated.

[@BrentBlanchard]

It would be interesting to see the unit running with the hole in the heat exchange too. Great video overall, it's really helpful to know a way of checking the system myself.

[@RealFuzzyPickLE530]

This is a neat trick, but dont rely on it. You need a combustion analysis and CO report before you can conclude that there are no cracks. This man is also dangerously ignorant about the dangers of CO poisoning. In his last video he stated you shouldnt be concerned about anything less than 100ppm of CO. At that level you will have irreversible damage. This guys advice about this subject is actually dangerous.

[@caidhg]

little bit harsh don't you think, I'm sure he's aware of the dangers of Co poisoning, he never said you don't need a CO detector in your house if you do this. he's just showing you how to check if you have a failure in your heat exchanger which could save somebody a bunch of money just on diagnostic charges alone.

[@Ratlins9]

@fuzzypickle5307 I saw that video and he stressed the importance of having a CO detector. Now regarding ppm of CO, the chart displayed in that video was acquired from Boiler and Machinery Engineering Bulletin, Federal Register, Vol 45 and Industrial Toxicology 3rd Edition. If you have a disagreement, take it up with them. Where are your videos helping homeowners from getting ripped off? I’ll wait for your response.

[@BrentBlanchard]

Oh yeah, CO detectors on every floor. I meant checking as in if some tech says I have a cracked exchange and shows me pictures, there should be other signs besides a photo that may or may not be my system. Unfortunately there are some dishonest folks out there happy to replace perfectly good, working units.

[@Thomas-xm5ym]

@@RealFuzzyPickLE530…..aaannnddd that’s why no one likes you.

[@hitekrednek66]

OUTSTANDING INFORMATION SIR! This was such a good demonstration. I will be trying this on mine just to practice my newly acquired DIY knowledge (less the hole of course😂).Thanks for this information. Keep them coming sir!

[@davidgentz1731]

Good job I'm in the same field and that was a great presentation

[@philliplangley9302]

Thanks, i am having problems with my furnace now blows cold air, I'm going to have a tech come out and look at it to see what the problem is, now I'm a little wiser on how the furnace works.

[@bryangiardino9058]

Good way to test for sure, but saying a technician is scamming you if they find a crack, but because its so small and not “doing anything” to the match flame is not true. In my province, if we find a crack, we are supposed to shut the unit down or risk our gas ticket. Basically a cracked heat exchanger in any way is supposed to be replaced.

[@KodieIvie2]

That's what the American Gas Association says. Which is who people should listen to above any tech or guy putting videos on KZbin.

[@DanRussell-q8s]

Great demo and will save you money and the potential of something bad happening !!

[@natehirsh]

Thank you very much for teaching me such a critical stage.

[@snygsk]

You are amazing for demonstrating this test.

[@gnic76]

Thanks HVAC Guy, that was an informative vid. An easy enough test to do periodically, to ensure furnace is functioning as it should. 👍

[@RealFuzzyPickLE530]

Be wary of this guys advice. You need a combustion analysis and CO report to know for a fact that it is not cracked. If it is, you and your loved ones can die, or suffer irreversible damage from CO poisoning. This guy may have good intentions, but he is clearly not a professional.

[@gnic76]

@@RealFuzzyPickLE530 Is still nice to know how, if a home owner is concerned, after which, if in doubt it can be pursued further with a professional.

[@charlescernosek]

If somebody told me this, I would ask them to leave. Even if your at 5 or 6 pm co it's a problem long term exposure is dangerous. Google it.

[@natersalad889]

​@fuzzypickle5307 just have carbon monoxide detectors through out the home like you should anyways, not rocket science

[@lisaryder1668]

That was an excellent video explaining how home owners can ck their unit . Much thanks to you for sharing your knowledge that's so very helpful. Blessing to you

[@MichaelwAEL]

Many thanks for all of your education. You are awesome in every regard. I am watching all of your videos. They are excellent. I wished you were my HVAC guy.

[@BryanTorok]

This pretty much confirms something I've always thought. The draft inducer blower creates a low pressure inside the heat exchanger and the main blower (fan) creates a high pressure outside the heat exchanger. Air always flows from high pressure to lower pressure, so as long as both blowers are running, there is no way for combustion gases to leak out of the heat exchanger. In older less efficient furnaces that lacked a draft inducer blower, it was possible for CO to leak into the heated air stream. Still, CO and also smoke are nothing to be complacent about. 40-some years ago my then girl friend and her parents had a near miss with an older furnace with cracked heat exchanger dumping CO into the air. Another family that I knew of died because a bird nest blocked their chimney flue. Having smoke and CO detectors is a very good idea. Also, it is good to get a CO detector that displays the level even if that level is below the alarm level. Long term exposure to low levels of CO is also harmful.

[@DCHVAC]

This isn’t true at all. The main blower will counteract the inducer and cause a flame rollout condition or turbulence pulls the exhaust fumes into the plenum.

[@JohannnesBrahms]

You can also put a carbon monoxide detector in front of a supply vent for a few weeks to see if there is a reading.

[@RobertTuck-vo8cw]

The inducer fan creates a vacuum through the heat exchanger and pulls blower air in. The CO does not get into the room - Unless it is a huge leak.

[@JohannnesBrahms]

My inducer fan blows air into the combustion chamber and out the flue. In the other case, if there is no carbon monoxide being forced into the supply ducts, then it wouldn't be a hazard for the occupants. @@RobertTuck-vo8cw

[@tedlahm5740]

@@RobertTuck-vo8cwUnderstand your statement. Under this the INDUCER is actually pulling air form the ROOM air that is in circulation. thank you

[@tommypitcock9928]

I have diagnosed a good many bad heat exchanger that was leaking co2 in to homes .and had caused illness .

[@btu64]

Thank you for this video. With the weather getting cold, I've been thinking about this.

[@rayzerot]

Even easier- run the blower and stick your manometer in each tube. Any pressure change indicates airflow from your blower into your heat exchanger and proves there is a crack (of any size)

[@thecatdaddy1974]

That would work fine for techs, but he is showing how to do it for homeowners to keep from getting scammed.

[@donreahm5512]

Can a heat exchanger get clogged

[@EnigmaticJack]

⁠@@donreahm5512yes. More common though is with a high efficiency furnace with the secondary heat exchanger, the secondary sometimes will get clogged. I’ve also been to some 80% gas furnaces that actually sooted up the heat exchanger like oil would due to a bad fuel/air mixture

[@drillsgtbrew]

Great Job-If you are ever in Milwaukee, WI I will will take you out for some beers and dinner at one of many famous taverns.

[@billy5032]

Closing off some of the supply dampers might help raise the static and help accentuate an issue.

[@kimballwhite]

Great video! Looks like that is almost the exact same model of furnace as my grandpa’s!

[@jayneerindefranco3085]

Thank you so much for your great videos. You saved me over 400 dollars on a service call. Keep up the good work.

[@LiuKang-tu8ub]

Well done! I will have to try this method. Thank you for sharing.

[@danielzertuche9893]

Good preventive maintenance tips especially the winter times or anytime. Thanks !

[@jeffbova-im7on]

ive learned alot from you whether its ac or heating, i doubt i will get scammed, thank you!

[@calebbroadhead348]

I'm new to this, but even if it does have a small crack, it's better to replace it then to forget about it and those crack(s) become bigger and more deadly. Overtime it will also smut up the inducer and your exhaust stack which is an indicator that it has cracks.

[@larrybell4599]

Great demonstration. Thank you for sharing this and many other HVAC tips.

[@Regii_HVAC]

Companies do try and sell new equipment but it’s still important to tell the customer that cracks never get smaller or seal up on their own, they only get worse and it doesn’t rule out the fact that in due time this crack will leak CO into the ducts if there is indeed a crack

[@EnigmaticJack]

Just a word of caution, I’ve been in this business for over 30 yrs. I’ve used the “match test”, powder puff into the burner tubes, manually disassemble and check with inspection mirrors and now also inspection cameras. There very well could be a hole or crack and you might not get a discernible flame action at the entry point of the tube. Most techs I know these days use a camera and can show you “live” what they find. And no, a crack does not automatically mean CO will get into your living space. The problem is the potential is now there. And if you’re a tech checking and signing off on a furnace you have to make your decision on the side of caution.

[@johnyoung11]

Great diagnostic!

[@davidgenie-ci5zl]

I found out my heat exchangers was cracked when flames shot out the furnace louvers and ignited the nearby wall board. Fortunately I was at home, heard the smoke alarm and put the fire out. Furnace was about 55 years old. The replacement was nice, and shortly paid back the cost in reduced gas consumption.

[@pgb1913]

Excellent video!! Thanks for showing us how to test heat exchanger

[@mapcelo]

This explanation is perfect! Thank you very much!

[@Geonious]

I hate crooked HVAC techs!! Thanks for your videos!

[@joewirts6616]

One of the best videos I have seen so far. Thanks for doing this video.

[@CommonSenseFishing209]

Need to test with blower door closed. Basic draft test. No flame required. Just turn on blower and see if any air is coming out of burners. Good stuff. Simple check. But remember to always check with blower door closed.

[@rodneysnook8252]

Thanks for that information. I really appreciate it. You do good work.

[@redbluff2583]

One of the best channels on you tube

[@WBBClips]

Can the leak be patched some aluminum tape or solder?

[@luckychucky3426]

Thank you there's a friend of mine I think can use this information very well done congratulations there's something I've never knew and every homeowner should know

[@tinysand3517]

We need more videos like this the HONEST DIY HVAC Guy

[@Choirboyjr11]

You can have a cracked heat exchanger and not have flames dance like that. This flame test is only useful if the crack is massive. Most of time when cracks are found, it is on a general maintenance and the cracks are small but present. Cracks are found, but not bad enough to allow this flame test to work. The manufacturer and the gas company both state that any crack larger than a 1/4" makes the furnace deemed as "unsafe". Not dangerous, but unsafe. The problem then becomes, when will it get bad enough. As the metal heats up, it expands and the crack spreads, therefore every start up that crack is likely getting worse. If your HVAC technician is trying to scare you into a new furnace, that's shady. Ask your technician to show you in person there is a crack, if you have any doubts in the technician. Any good HVAC tech will have a CO detector on them also.

[@diyhvacguy]

1/4”?!?? That’s freaking massive. The reality is a tiny crack is not unsafe. Does it have the potential over the year sure, but that’s the point of checking. And obviously the most important thing is to have CO detectors and make sure they’re operable

[@Choirboyjr11]

Hey, I agree on 1/4" being very small but I don't make the rules. CO detectors are CO alarms. The lowest threshold is 40ppm for 4 hours or 200ppm immediately. Both are arguably too high. I've had flue rot out, dump CO into the house and the 1 year old CO detector not go off. Batteries and test feature were good, so I don't trust them. But you do you man. I like the work you do and I know you have good intentions. Have a good holiday.

[@Jon-hx7pe]

any crack is unsafe. ul co alarms need 70ppm to go off unless the exposure is over a long time - they are time weighted. @@diyhvacguy

[@recycledpaul9728]

Please run the heater so we can see if the flame is still blue or lots of yellow flames. Thanks

[@ThomasGray-f1s]

Checking a hx with a candle or matches is something we did back in the day. What happens when the hx crack is so small it doesn't affect the flame of the match? This is why good techs use a combustion analyzer and not outdated methods

[@anyhourdlaird8714]

I like what he’s doing here. My only concern is the American Gas Association states any visible crack or hole is reason for requiring replacement of the heat exchangers or the furnace. You could have a good sized crack that has not fully opened up to interrupt the flame in this example of this video. However you can’t tell a homeowner they are fine to operate the furnace because it’s not making the small flame on the match jump around. It may not be in this example however it’s not a matter of if, it’s a matter of when. I’ve pulled hundreds or thousands of blower motors and evaporator coil doors to inspect heat exchangers. This is like saying well your car tire is showing wire on the inside of your wheel. However car drives fine for now so you do not need to replace the wheel. Again not a matter of if, matter of when that tire will blow. I do however see larger cracks and holes that this test would come in handy however most homeowners understand right away when I bring them down to the furnace and show them exactly what I’m seeing. This dude does seem like someone I would hang out with though. Seems like good people for sure