Gas Furnace Smart Valve, Ignitor, and Flame Sensor Troubleshooting!

In this HVAC Diagnosis Video I go over the Ignition Troubleshooting of a Smart Valve, Ignitor, and Flame Sensor by Honeywell. I show the voltages of each of the wires connected to the smart valve and where they are located, how to test the flame sensor, how to test the hot surface ignitor, what kind of hot surface ignitors are available, how to change out the ignitor and flame rod as well as adjustments to the pilot and how the whole thing works together for ignition. Supervision is needed by a licensed HVACR Tech while performing tasks as Experience and Apprenticeship garners Wisdom and Safety.
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Information in this video is intended for educational purposes only. Any work related to the topics in this video should be performed by licensed technicians or by apprentices under the supervision of licensed technicians. AC Service Tech LLC is not responsible for any possible damages or injuries caused by the use or misuse of any information provided.
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[@acservicetechchannel]

Tool List- www.amazon.com/shop/acservicetech Support- www.patreon.com/acservicetech For those that are looking for the tools used in the videos: (Linked Below) Here is a link to the UEI DL389 Multimeter used in the videos- amzn.to/2av8s3q Here is the link to the Fieldpiece SDMN6 Dual Pressure Testing Manometer with Pump-amzn.to/2jyK5Ka Here is a link for the Supco Magnet Jumpers amzn.to/2gS4h6z Here is the link for the Irwin Wire Stripper/Cutter/Crimper amzn.to/2dGTj2V Other tool links can be found in the video description section. ACSERVICETECH is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.

[@waynemathews1]

Inducer fan on Goodman furnace

[@michaelmace924]

Thank you for this video. Awesome video, very well done.

[@tedallen9078]

I just left a service call. I discovered the flame rod had come in contact with the metal shroud that is situated over the rod. the assembly had been tampered with. the shroud was slightly bent enough to touch the flame rod. flame would not make. all i had was the draft motor. after viewing this video, i have discovered a means to prove a good gas valve. and how to carefully inspect the entire circuit without going down a rabbit hole. great video. i won't forget the nightmare of a service call that this last one put me through.

[@ninjaskater]

The blue wire on my board was loose thanks to your video my furnace works again

[@ummagumma21]

Cleaned up the flame sensor rod and the pilot assembly and I'm back in business, thank you for this great content!

[@jpchapboy]

Really great explanation on smart valve function thanks.

[@jacobmery8874]

Great video, thank you so much for your time and effort! This helped me troubleshoot and get my house heating again!

[@acservicetechchannel]

Great to hear!

[@bettyallen2279]

Was not what repairman said it was.. igniter or smart valve what next??

[@Jtagle77]

Great Video! Thanks for sharing

[@LuckySevens255]

Your video had everything, even the parts links for component I found I needed to replace after testing my Honeywell SV9501

[@dcrickerson7611]

You always do a great job of explaining things. Great video.

[@acservicetechchannel]

Thank you very much DC Rickerson!

[@monterrozacesar5]

Excellent video. Thanks for sharing with us. Thanks God we still have unselfish people sharing and giving their time so we can learn more and become more useful for our company and our customers. Thank u again Acservicetechchannel

[@acservicetechchannel]

Glad to help monterrozacesar5!

[@IALewis]

Great video. My black wire had no voltage. I removed the new ignitor connecter and checked the gas valve and had voltage. The connecter on the black wire was not making contact with the gas valve.

[@omaigadbrochacho2812]

Dealing with old rtu out on the field… this will def. help! 👍

[@Gexxon]

EXCELLENT EXCELLENT EXCELLENT explanation of a smart valve pilot ignition system. Just was I was looking for too. I like the fact that you took the time to disassemble the pilot assembly for us noobs. LOL. It's exactly what I needed to see and learn how/what to do, as my igniter assembly, of the same type as yours int he video, seems to be the issue with my furnace not firing up. I ordered the replacement part, changed it out myself, and I have heat again. Woohoo! Thank you for making this. A big help that saved me time and money.

[@vnesmuonnam]

nice setup and you made it easy to understand. Thank you.

[@acservicetechchannel]

Glad you liked it!

[@NZBoatie]

Wow! Thanks for helping a Kiwi down this side of the world! So this was very handy!! My pool gas heater stopped working last week! Has the same valve. So I put a meter on it and managed to get 24v on the heat igniter wires which I figured was the case as it was glowing. I just couldn’t get the pilot to start. The black wire to the rod was weird! It was fluctuating between 18-45volts? So long story short, it turns out the gas jet at the pilot end was blocked! Cleaned it out and got a good pilot. But then next issue...main burners would start but go out every time after about 10-30secs! I thought it must be the varying voltage in the rod wire so ran a new earth wire from rod to valve switch in circuit, no change. Tried adjusting the rod and heat receptor arms in case they were out of alignment, no change. Ran earth wire from pilot to valve body, no change! Spent ages trying to figure it out. Turns out, I managed to fix the issue by dropping the pilot assembly down a little below the main burners. It seems to be getting too hot once main burners kicked off and maybe a safety was switching it off??? Any ideas??? As soon as a dropped it down, the main burners kept running! Seems to be working perfectly. Tried moving back up, burners went out!!! So, just thought I’d share this in case it helps someone else! No idea why it worked last week in that position and not anymore? Can only think when I took it out I must have bent the bracket or something causing it to lift too high? Hmmm??

[@johanchalco5117]

Good. Video. It brings back memories of York gaspacks about 14 years old and some ducanes I've worked on.

[@acservicetechchannel]

Yes, thank you Chalco Home solutions!

[@ejosephsimon]

Question I have a Honeywell SV9501M2528 if I put the IGNITION SYSTEM CONTROL SWITCH to the off position my hot surface ignitor lights up but of course pilot & burner do not light, the switch being off prevents that, But then when I switch it to on inductor fan kicks on but hot surface ignitor never starts glowing? Is my Smart valve bad or could it be something else? thanks..

[@DarrenTabor]

What if you’re not getting any gas pressure from the pilot tube or main gas exit and the igniter just glows red and nothing happens? I have 24v going into the controls on black and blue.

[@abdulh63]

great channel. have learnt a lot! from the uk

[@jayjackson5748]

Great videos! I have a Sterling tubular heater in my shop. The main burner will not stay lit. I've checked everything there is to check and have even replaced the smartvalve and flame sensor. I've bypassed the high limit thermostat and ventilation proving switch. I have 11 WC of propane pressure and the flame is strong. I've ran a ground wire from flame sensor to smartvalve. It puts out 113v to flame rod. It has steady 5.8 uA of dc current. When it first starts up the main burner will stay on for about 2 min. on next attempt it stays on for about 45 sec. , then 30 sec, 30 sec again and last attempt 15 sec. So each time it stays on for shorter time. It then flashes 6 times indicating issues with flame sense. The whole unit is grounded properly. It worked fine the first 2 winters but then started acting up. Since it's in my shop it has very little time on it, probably less than 100 hrs use. It's all clean as new. The flame sense grounds through the aluminum gas tube from smart valve body as shown in your video. Even though there was continuity of less than 1 ohm between valve and flame sensor I added a ground wire between valve and sensor. I can simulate signal loss by disconnecting flame sense wire while its running during that 2 min cycle and burners cut out within a couple seconds. Then it tries again when I reattach. Everything is tight and clean. From what I've read, the pilot flame is supposed to stay on even when the main burner starts. It seems odd in that if the main burner didnt ignite, the pilot flame will satisfy the flame sensor to keep main valve on therefore blasting the propane out without it being ignited.Seems like a potential for explosion. I would think the pilot flame should drop out when main burner turns on, then main burner would be making flame sensor happy for the duration. As an experiment, when main burner was on (flame ignited), I took pilot flame burner/flame sensor assy away from main burner area (kind of like what you have shown in video and it has a ground path) and it still had 3uA of current. So it stayed lit for about 2 min as before. The smartvalve is a 9540 model. The igniter/flame sensor is a Q3400A. When looking at the Honeywell document for measuring flame current. It says that for a SV9540 - if current is less than 0.8 uA then check for low gas pressure, flame rod contamination, poor current path, etc. If it's more than 0.8 uA then replace the SV9540. That doesn't make any sense. It doesn't give any range of what's good. So what it is saying is that it must be exactly 0.8 uA. Which seems really low. I keep wondering if it is a typo. Even in the document a footnote says flame rod should be capable of giving twice minimum threshold even under poor conditions. So twice is 1.6 uA and I'm getting 3 uA with just pilot flame and 5.8 with main burner. Also, watching the ammeter, it never flinches at all at the moment burner drops out which would indicate a brief drop in flame current if it did. Well sorry for such a long story here. Just hoping to give you as much info as I can. Any help would be appreciated. Thanks!

[@acservicetechchannel]

I gave a couple suggestions in the email. It sounds like you have researched this a lot and seem to understand what is going on or heading in the right directs. When you say that you ran a ground wire from the flame sensor to the smart valve, do you mean from the pilot head bracket to the ground on the gas valve? That would be one step you could take. The other is stepping back and looking at the ground testing for the furnace itself. I know that sounds silly but it sounds like you hit a lot of the testing points at the flame chamber except maybe that ground wire from the pilot bracket. There shouldn't be a wire going from the flame sensor to the ground. - check out this video and check out the testing for a ground problem part - kzbin.info/www/bejne/gqXJmJuLjsufY5Y -- also check for things like the input voltage to the gas valve. Let me know how you make out, thanks

[@jayjackson5748]

Yes, The ground wire I ran is from the pilot head/flame sense/igniter bracket back to the smart valve body. Basically parallels the gas tube. I checked ground from burner head and heater chassis back to valve and to earth ground at receptacle and it's all good. But I will go back over everything again though. There was 26 vac going into valve. I'm going to further investigate the earth ground all the way back to the breaker panel as well. I know it's going to be something easy and simple when I find it.. :-)

[@jayjackson5748]

UPDATE! Well Hallelujah! I finally fixed my heater! Last summer came and I once again forgot about heater. This fall I decided I was going to fix it or set fire to it. After pondering what I had done before, and the way it was kicking out so systematically I went back and looked at ventilation proving switch. Although I bypassed it before, it must be done in sequence, maybe I didn't do it correctly before. I put a volt meter on contacts and sure enough, after running about 2 min they opened up, Then flame would drop out and restart, the contacts would close again, after about 45 sec they would open up again and flame would drop again, this same sequence would happen 5 times and then do a 5 minute lock out because of 5 flame outs... The flashing LED indicator would indicate EVERYTHING BUT the proving switch according to chart on heater. If the switch would have stayed open, then perhaps it would have indicated the proving switch. Evidently the intermittent/erroneous operation made smartvalve think it had other issues. I bought a manometer to check for sure. Using it I could see that it had plenty of pressure differential. The switch is set at .40 WC. I had a pretty consistent reading of at least .60 WC with manometer. So it was evident that pressure switch was intermittent/bad. I replaced switch and it has worked fine for the last few weeks. Sorry to ramble on but hope this may help others.

[@PaulHVAC1]

@acservicetech Very good video and very informative to the HVAC techs out there. One more item I would add is when testing the Carbide igniter, Honeywell states, at room temperature, the igniter ohms should be no more than 10 ohms. Above that it's advisable to replace with new igniter. Keep up the good videos!

[@acservicetechchannel]

Thanks for adding that!

[@youdontknowme5969]

Thank you for this. Mine sometimes doesn't ignite. I wonder if the sensor and pilot just need a cleaning. I hadn't watched it misbehaving in action yet---only heard it from the other room, and it'll retry in 5 minutes just fine (so far...)

[@jvgm9154]

Clean and explicit video, thanks

[@acservicetechchannel]

Thanks JVR!

[@michaelmace924]

Dude, I've been a service tech for 22 years & believe it or not I've NEVER had to service a Carrier smart valve set up, until today. I felt like such a dummy with the customer over my shoulder, so embarrassing. It was actually a Heil and their tech support is bullshit. You have to have your HVAC supplier call them on 3 way and my Heil Supplier are douche bags, they didn't have time and couldn't help me today. If I was able to watch your video earlier I would have been golden. I picked up a board, pilot assembly, and the gas valve. I was 99.99% sure it wasn't the assembly because I didn't have 24vac going to the igniter but I wasn't sure if it was the board or the valve. The schematic wasn't very good. It didn't show what each wire did, it was more or less a pictorial. I like using a ladder schematic when I'm not sure of the wiring. Anywho, I changed the board and finally the valve. I hate being a parts changer. Luckily, I was able to return the board. I am now a subscriber, great video.

[@acservicetechchannel]

Thanks a lot Michael! Glad to hear it helped!

[@chandarasena]

Thank you very much, your explanation and shows are very useful tools.

[@acservicetechchannel]

Thanks!

[@asiakevin]

When you're checking resistance on the hot surface ignitor, what should it be?

[@hedgewoodtv]

I have a a smart valve system, but it also has a control board. I'm not getting my draft motor to turn on when I call for heat. Limit switches and pressure switches are good. Motor is good. Does the smart valve control the draft motor or is it my control board?

[@oldscar6169]

Great explanation and presentation!

[@Juegosdecartas101]

Thank you for a very helpful explanation video 👍

[@acservicetechchannel]

Thanks Jorge Mejia!

[@tommyirish9685]

Do you know if the newer valves are giving a lower fluctuating voltage on the flame sense post? ( Cycles from 20v goes up to 50v then keeps repeating same reading)

[@westsidehvac1097]

great video

[@556guy4]

I have that same set up in my heater and have problems. Not ignighting. Igniter is not even coming on. Cleaned the flame rod

[@mark.r8900]

hi, i was working on a rooftop with the same smart valve. but when i measure the black wire (flame sensor) i was only getting around 50vac. The flame rod was very clean. Why is that you're getting around 180vac but mine was only around 50vac? thank you for all your help.

[@hvacworkshop4791]

I got 144v

[@ronaldfuhrer]

If I have this system, can I light my furnace manually, till I can get the part

[@astindersinghera766]

great video, learned a lot. Sv9500h gas valve is not producing 180v for flame sensor, only producing 2.0v . Igniter comes on, pilot comes on but no main burner. Please advice what I can do. Can I get a replacement IC board. Or is there components on board has failed, how can I test it. Thanks for any help you can provide.

[@thefred0215]

What inch water column should you get at the pilot tube?

[@adamcraig1568]

Where does the orange wire go to off the smart valve? The board?

[@patricktravis93]

I replaced one of these today and now the pilot seems to have way too much pressure. I'm not sure if it had any similar issues prior to me working on it. Is there any kind of pilot orifice that goes in this anywhere? Something that may have fallen out and I didn't notice?

[@jarvisjackson1616]

Heymy smart valve makes a loud clunking noise water was leaking on it when roof was leaking is it possible it shorted out and if so how do I replace it thank you

[@garyogg-ge8zz]

very very helpful!!!!!!!

[@rocker8692]

Another excellent video.

[@acservicetechchannel]

Thanks Cahd Tinsley!

[@deanmartin1966]

Excellent video.

[@acservicetechchannel]

Thank you deanmartin1966!

[@jcmeyer5]

Hi there. I have a Dayton heater that I am trying to diagnose. I’ve checked all the different voltage you mention, and the only deviation I have is in the flame rod - I get 24V AC, which I have read someplace is proper for my valve SV9500M-2562 (propane). The heater will light and turn on, it then turns off after about 15 seconds. It then turns back on, and shuts off after 10 seconds… then 5 seconds… then 4 seconds… keeps on decreasing. I’m thinking something is getting hot and shutting it off, and subsequent heat events take less time to heat it (whatever it is) up. What other sensors should I check?

[@bobsoft]

Awesome video explaining how this setup works. I have the exact same system on my furnace. Just trying to figure out why sometimes it will not ignite and blows cold air.

[@acservicetechchannel]

Does it at least ignite for a split moment and then shut off or no ignition at ll? Does the 24v hsi turn orange and heat up?

[@bobsoft]

I took it apart and cleaned it like you mentioned in your video and so far so good. I will check what you asked if it happens again.

[@acservicetechchannel]

Thanks!

[@bobsoft]

That was short lived. The furnace came on without heat. The igniter should be fine it was 4.7 ohms when I had it out for cleaning. Is it safe to assume the smart valve has a problem with the internal circuit board?

[@acservicetechchannel]

If there is a problem with the igniting of the gas then possibly depending on if you have a good solid above 24v heat signal into the valve. If it is after ignition when you are having the problem with it shutting off, you may want to try replacing the flame rod and hsi combo as sometimes we have problems with the flame rod being too small and too much resistance in the wire to rod connection. It could also be a loose ground or smart valve board, thanks

[@kevinkevin9448]

Thank you again I actually have a sv9500m 2500 are these valves interchangeable

[@acservicetechchannel]

You would just have to look at the wiring. The newer version has more wire connections than the older one. There are two main types of honeywell smart valves used predominantly, thanks

[@harveyweich1936]

I have the same valve on my Dayton unit heater it works intermittent how can I check it?

[@kevinkevin9448]

Thank u ,so correct me if I am wrong so if the ignitor resistance is ok and it glows and u have good gas pressure .the pilot black wire should have 110 volt and the valve should send gas to pilot and the flame rod recognizes the flame and open the main gas valve thank u again

[@acservicetechchannel]

The black wire will have about 180v when the pilot tube is supposed to have gas flowing throughAll flame rods have 80v to 180v ac voltage and the smart valves typically have a higher voltage, thanks.

[@tzxlyd3828]

Well I got it to work but if it is bad I do not know how much longer it will hold up -- it is the older model SV9500M2682 and from what I can tell it is no longer being manufactured. I believe the replacement part for it now is model SV9501M2056 (also SV9501M2528). I assume you would recommend that I get a multimeter and test the voltages before making any determinations -- it just seems until I can do that the Smart Valve is the obvious problem if it is not a short with that clip.

[@acservicetechchannel]

It may be the pressure switch, flame sensor and hsi combo, the grounding, or the smart valve but I couldn't tell without readings, thanks

[@EthanWood757]

I’m only getting 24v out of one of the leads from the valve to the igniter. Any idea what that could be?

[@dakota4766]

Well done

[@hozerhvac4406]

Great video. I hate these damn valves lol

[@acservicetechchannel]

Thanks ha ha

[@hooptienation7072]

Thanks man

[@johnvandusen300]

My SV9601M4167 smart valve isn't igniting the pilot gas. I've got a new HSI as well as gas orifice and have verified that gas is present during ignition sequence. Input voltage to the valve is dropping from 26 to 20 during the sequence with a max of 19.5 at the HSI after about 10 seconds. Any suggestions are great appreciated as I'd rather not keep throwing money at guesses.

[@hvacworkshop4791]

Just a guess, maybe need a 24v >=40VA new transformer

[@IshockO]

Can you make a video on how to check ground. I don't exactly know what this means but I do know if you don't have ground your flame sensor won't work.

[@darryls5843]

Nicely done! Still hate to walk up on a SV, but I would have had an easier time with it if this video would have been out years ago.

[@acservicetechchannel]

Thanks Darryl S!

[@joaquinayalarosales7441]

Very cool thanks

[@jawanioo]

Great video.great channel. Thanks for your effort.

[@acservicetechchannel]

Thanks jawanioo!

[@terrpe144]

Great video, much thanks!! I've got a question. I'm having some trouble with the on/off switch. If the switch on the gas valve was in the off position, would the ignitor light???. I'm dealing with a possible broken switch and Im trying to confirm if it's on or off. Everything is working except no gas flow to pilot.

[@swapnas6966]

Thank you for great video. I have Honeywell SV9541M2094. I am not getting 24v on ignitor blue wires. I seeing 24v on one of ( black sideone) blue wire to ground. What could be the issue? If I manually use lighter close to pilot gas, it fires up and furnace start working. Any help on this?

[@DaBorderhopper]

what if everything checks out and valve clicks like it should to open.the igniter glows but there so no gas flowing through what would cause that

[@tboneproductions2453]

Excellent videos. Thanx so much

[@acservicetechchannel]

Thanks Tbone!

[@silver200306]

Hi I converted mine to propane. Same smart valve as yours. I’m using it for a fire pit outside only problem I have is that at the psi flow from the tank to the valve the burner won’t ignite even though the igniter is glowing. But once I lower the psi to about 2-3 psi it turns on, what do you think is the problem? Thanks.

[@jpol3808]

For anything to ignite it takes flame or an ignition heat source, fuel which you apparently have a ton of and it must be combined with oxygen to combust. By lowering the pressure to get it to ignite, it seems like the high pressure isn't allowing enough oxygen with it as it passes over the ignitor to ignite. That's my thought. As long as the lower pressure is within low limits spec you should be good. No longer flooding the system with to much fuel. Anyway that's my thought.

[@cchavez302]

What if the hot surface ignitor is on all the time is that just the valve going bad

[@NOTPMOC213]

Quick question does the pilot stay lit 🔥 after main flame turns on?

[@smtimo]

Great video to understand how the furnace works. Would be possible to have faulty Igniter/Sensor that works with thermostat without C wire and does not ignite when replacing with thermostat connected to C-wire? Also, I measure the resistance on cold HSI and it is 4.1 oms. Trying to troubleshoot the 19 years old furnace when newer thermostat connected through C-wire.

[@acservicetechchannel]

The c wire or battery powered thermostat shouldn't be a problem. You just want to make sure that you have 24v on the w thermostat terminal when calling for heat at the thermostat, thanks!

[@kevinkevin9448]

Pilot seems very low any thoughts ???

[@phillipjoy8191]

Great video

[@acservicetechchannel]

Thanks Phillip Joy!

[@waterheaterservices]

Very well done

[@acservicetechchannel]

Thanks Jim Rr!

[@mikekahidi1891]

Great Video, only regarding the reading of the flame sensor, shouldn't be 180 Mili volt instead of 181 volts? Thanks

[@acservicetechchannel]

I was mentioning the ac voltage going from the board in the smart valve to the flame sensor. The mv is carried back to the gas valve via the ground on the pilot tube so there isn't a wire to pull apart and put the meter in series in order to test that, thanks Mike!

[@jpol3808]

I cut the sensor wire and inserted the meter. I got 180v and 1.8 on pilot and 3 on main flame..... microamps. Unit runs fine after cleaning the sensor.

[@richardwuttunee9355]

Hey buddy , I have high voltage going to smart valve but no high voltage going to inducer motor to start it up , I jumpered all the safety limits and then jumpered out the inducer motor and it started , I ohmed out the ignitor had 4 ohms . So I diagnosed a bad smart valve , but ppl haven’t went ahead with repair yet , is there something I’m missing here on the proper diagnosis ? It has an 8 pin low voltage Honeywell type molex plug to it as well, thanks In advance , highly appreciate your videos !!! 🙂

[@tommyandtammy1]

I have an hvac unit that I just replaced the control valve with an exact replacement, but now I notice that where the flames go into the heat exchanger there are some orange flames flickering between the burners. It's not blow back because It happens even before the main fan comes on. I have checked It with my pressure meter set It to 10 for lp gas, and checked It with my carbon monoxide meter and there Is no carbon monoxide coming from the vents Into the house and the carbon monoxide coming from the outside flue vent Is only 17ppm. I looked Into the heat exchanger and couldn't see any cracks. This Is a 4 ton outside unit made by york. It is working fine just concerned about the orange flames. The flames going Into the heat exchanger are blue just like they should be. Also new Inducer motor It Is working fine. New Filter.Do you have any suggestions?

[@jeffvancoillie7519]

Gas boiler pilot intermittent control module trouble shooting

[@tzxlyd3828]

I do not have a meter but I believe my smart valve is bad. I was using a bread tie to pull on the igniter clip that locks into the smart valve because I found if I move that clip the pilot light would ignite. I had the bread tie pulling that clip in towards the pilot reset knob (it was wrapped around the igniter clip and the reset knob) so that the pilot light would ignite and stay lit. The problem was the pilot would not stay lit until there was a click after the induction motor would start. If I pressed that igniter clip that fits into the smart valve backwards I would hear the click and the pilot light will light and stay lit. I found if I let that locking clip go into the normal position the pilot light would shut off. Now after a couple of months the pilot light will not ignite no matter how much I move that locking clip. I did notice when I would move that locking clip that there was a small spark right where that clip fits into the smart valve just before the pilot light would ignite. Do you believe the problem is the smart valve or could there be a short where the locking clip fits into the smart valve?

[@tzxlyd3828]

So the bread ties finally stopped working. I was able to get the resistance reading on the hot igniter and it is 4.8 - 5.0 ohms. The pilot light will not ignite but I can no longer hear the click from the thermostat calling for heat. There was a series of clicks when it is working that I am no longer hearing so now I do not know if it is the thermostat (original since house was built in 1969) or the smart valve igniter module Honeywell SV9500M 2682 HQ1009093HW. What do you suggest?

[@mark.r8900]

Hi, my hsi had about 4.8ohms. Both blue wires have 24vac. But the hsi is not glowing. Black and blue wires also have 24vac. Is it bad valve? Thanks

[@stevelarrabee2857]

Same issue here, what did it end up being??

[@BM-hb2mr]

Need help. Lol I have everything you are saying but no ignition on 24 volt hot surface igniter. Please help. My girl had no heat and I'm worried about the kids and the animals. Very good video

[@acservicetechchannel]

If you have 24v to a 24v ignitor and it doesn't glow then the hsi is bad, thanks!

[@CarAholic86]

Could you do a comparison video for the different Honeywell smart valves and how to trouble shoot the different ones.

[@acservicetechchannel]

I would like to do something like that in the future, thanks CarAholic86!

[@7evenstreams]

What is the valve that you’re working on? I have a bad connection between the 3 pin connection and the igniter, everything tests good individually but when connected, the igniter doesn’t receive voltage. Thoughts?

[@acservicetechchannel]

That is a honeywell smart valve, thanks!

[@abelolivas7374]

Same replace it

[@kevinkevin9448]

My hot surface ignitor gets red hot what do u think it could be the pilot flame doesn't light ?? Thanks

[@acservicetechchannel]

If it is a smart valve like in the video, check the inlet gas pressure and then the outlet pressure of the pilot tube. If there is good pressure going in and no pilot tube pressure while the hsi is red then the smart valve is bad, thanks!

[@josemontanez3034]

very good video frist time isee one

[@acservicetechchannel]

Thanks Jose Montanez!

[@MaxxHomesLLC]

I Have This valve. Hot plate lights, pilot lights and stays on. But then main gas does not start to flow. Then the furnace starts to blow but obviously there is no hot air. Do I need a valve or a board? Yikes I can't figure it out. Already replaced Hot Plate / flame sensor, and nothing changed.

[@MaxxHomesLLC]

There seems to be no separate circuit for the main gas valve it seems the Pilot gas valve and Main gas valve should open at the same time unless there's an internal timer. I believe my valve has failed

[@lgrullon854]

I am having a Lennox furnace, was having issues where the main burner was not coming up so I decided to purchase a new smart valve...went with the SV9501. After doing the replacement now the pilot will go on and the main burner would go on, but when I shutdown the furnace via wall switch the pilot does not go on. I check the actual rot and igniter and noticed the blue wires by the hot surface igniter as well as the black wire of the flame sensor were a bit melted. I am trying to understand what controls the pilot gas output. I know it comes from the valve, just wondering if the frame rot and the hot surface igniter are the one controlling the sequence along with the Smart Valve. Before I go ahead and purchase a new hot surface igniter I would like to hear your recommendations. Thank you.

[@acservicetechchannel]

The smart valve heats the hsi and then opens the pilot tube to let gas through. It is all controlled at the smart valve control board. I don't know why your pilot would stay lit without a call for heat. Does your hsi continue to stay powered too or just your pilot allowing gas through, thanks

[@lgrullon854]

@@acservicetechchannelBasically, I turn the gas on (safety measure during testing phase) then I proceed to turn on the wall-switch. After than I see the HSI glowing and then the pilot goes on then the main burner lights up. When I turn the wall switch off I see the main burner goes off but the pilot remains on forever. The first Smart valve that was there the burner didnt go on at all, I think the circuitry just got burn out or something so I went to ebay and purchased a used one....this one light up normally but I am having this issue with the pilot where it stays on all the time. I have the feeling that even when I open the gas line gas is getting release from the pilot orifice/hole automatically, I know is not a lot but as a safety measure I have resorted to close the valve until its all working. I am a little clueless on this one, your help is greatly appreciated.

[@lgrullon854]

I have changed the HSI and all is working 100% now. The old igniter was 15 years old, so I guess it served its time.

[@RockoRocko-rz7kx]

Thanks again for video, I guess I was wrong it wasn't the board it was the smart valve. Lol

[@acservicetechchannel]

Thanks Rocko99 Rocko99, ha!

[@antoniobuccio5664]

Infinitamente... Gracias.

[@KingKatura]

I watched a smart valve that was messed up, the igniter wasn't lighting, The guy took a screw driver & twisted something on the smart valve & the igniter came on. What did he do? & how the hell does it work like that? its something i didn't know about until recently.

[@tzxlyd3828]

So the bread ties finally stopped working. I was able to get the resistance reading on the hot igniter and it is 4.8 - 5.0 ohms. The pilot light will not ignite but I can no longer hear the click from the thermostat calling for heat. There was a series of clicks when it is working that I am no longer hearing so now I do not know if it is the thermostat (original since house was built in 1969) or the smart valve igniter module Honeywell SV9500M 2682 HQ1009093HW. What do you suggest?

[@acservicetechchannel]

You can jump from r to w in the thermostat to bypass that so you can see if that was the problem.

[@tzxlyd3828]

Sorry I did not know you had responded to my inquiry -- what do you mean I can jump from r to w in the thermostat to bypass that? Do you mean I can check to see if the call signal is being sent from the thermostat to the heater/furnace by connecting the r and w wires in the thermostat?

[@acservicetechchannel]

@@tzxlyd3828 Yes that is correct to take it out of play, thanks

[@joeyravage4798]

180 volts? You responded to Mike Kahidi but I can not decipher your answer. I thought it was millivolts as well. Please clarify.

[@acservicetechchannel]

This smart valve sends 180v AC into the flame rod and dc micro amps travel back through the ground. The only way to check dc micro amps is to cut the flame sensor wire to put the multimeter meter in series, thanks

[@randyosborn284]

@@acservicetechchannel So there's a step-up voltage in the Gas Valve? Cause your only giving it 24v... Good vid BTW!

[@PhuongHoang-kl5ui]

Can you do a video on how to convert standing pilot to spark ignition please

[@acservicetechchannel]

Thanks for letting me know what you would like to see Phuong!

[@вечная_мерзлота]

Shouldn't it be a milvolt and not microamp on flame sensor? I know these type of meters aren't capable of measuring microamp but will do milvolt.

[@fokuspimp360]

hey great video..can you do the 2nd generation smart gas valve. thanks

[@acservicetechchannel]

I would like to in the future yes. Thanks Floyd Davis!

[@jamesfagan93]

My smart valve is only getting 9.5 volts for the flame rod, not 150 to 180 volts.Bad gas valve?Great videos!

[@acservicetechchannel]

As long as you are getting a solid 24v to the gas valve and the wire going to the rod has no resistance or is not touching another surface than yes that would likely be the prob, thanks

[@jamesfagan93]

Yes it was the gas valve,running great now, Thank you

[@Andrico77]

Hi there,Great video - I replaced my smart valve and igniter about 6 months everything worked well until lastnight.So im troubleshooting now. I have 24v from pressure switch, 24v on hot coming into the valve.Question: for the 2 blue wires on the igniter - is there supposed to 24v coming from each blue wire...?Right now I only have 24v from one of the 2 blue igniter wires Your help would be greatly appreciated!!!!

[@Andrico77]

I checked again and I have 24v off both blue igniter wires.I believe I found the problem. Seems the black igniter wire is only registering 50 - 70 v and it fluctuates drastically. I believe you said that wire should be in the high 100's

[@acservicetechchannel]

That seems a little low but that still should work unless it is cutting out or something when that voltage is jumping. The flame rectification signal finds its way back through the pilot tube ground. Is that pilot tube tight in the gas valve without any pipe dope on the threads of the pilot tube brass connector? Also make sure that the pilot head and bracket are clean without damaging the hsi so that that the dc signal is able to make it from the flame rod, through the flame, and to the ground so that the dc micro amp signal is picked up at the control board of the gas valve. Is it firing for a few seconds and then just shutting off? Also if there is any intermittent problems, keep a close eye on that pressure switch. It may be trying to tell you of a condensate, combustion intake, or exhaust problem. Thanks

[@Andrico77]

Thanks, I think I may have put pipe dope Pilot Tube connector - but it did work for 6months ....No intermittent problems and doesnt fire at all: got 24 v on both blue igniter wires and and on the 2x2 connector pressure switch proven good aqs well. The ignitor doesnt glow at all and when I try to cycle I believe the pilot comes on b/c i smell gas for a bit - then it stops.The smart valve is only 6 months old .... How do i check for micro amps on the pilot tube

[@acservicetechchannel]

If you are getting 24v on the hsi and the hsi is not lighting then you may have a crack in the hsi. Take the hsi connector off and test for resistance. If the reading is 0.L or very high in the hundreds of ohms then the hsi is bad. Thanks

[@clarencehill7048]

What about.Inducer fan motor

[@acservicetechchannel]

just look up "acservicetech inducer" thanks

[@Guyhakverdi]

How do you check flame sensor when flame is on ? Like we can read on basic flame rods 2-4 ma

[@acservicetechchannel]

Unfortunately you can't unless you want to cut the flame sensor wire since the pilot tube is the ground, thanks Guy Hakverdi!

[@Guyhakverdi]

so if you cut it and measure it would you read somewhere between 2-4 ma? Thanks for sharing great vids.

[@acservicetechchannel]

Honestly when we start having intermittent problems with the flame we usually just replace the flame rod and hsi since they are all one piece and clean the pilot head. Flame rectification is simplified on this since it follows the pilot tube and goes right back to the gas valve board, thanks Guy!

[@Guyhakverdi]

The thing is you would't know for sure if smart valve control is bad or not. I agree with you I change the igniter with sensor and if it still giving problems replace the valve. I just hate call backs and usually happens during heating season lol

[@acservicetechchannel]

A tester can be made for this out of an old flame sensor connector and an old smart valve connector. The issue here is that they don't give us a value of exactly what it is because they don't want us to cut it but I would assume you are on the right track but the ma could possibly be higher, thanks

[@thonyperez2040]

Can you give a proper complete connection of it

[@Bink144]

Thanks for the videos they are very informative. But I do have a question. I just replaced the surface igniter in my sisters furnace, it had burned out. when I turned the power back on it fired up and ran fine, but never fired up again. I went back up and everything was working as it should the igniter heated up and i could hear the gas valve clicking open but not letting gas through. I tapped the gas valve a couple times and tried again and it fired off and ran fine so I turned off power and tested it 5-6 times and it worked as it should. I talked with her this morning and its not lighting again and ideas? Could it be a piece of trash sometimes blocking the gas jet at the surface igniter? ( I'm guessing I can't get that lucky )

[@IshockO]

Brent Gross start cleaning

[@acservicetechchannel]

Number one, with intermittent problems you could start with a status code light. Is it a new enough furnace to have an error code? IMon is correct in that you should clean what you can such as fine course unsoaped steel wool on the flame rod but NOT the hot surface ignitor. If you are working on a 90% efficent or higher furnace did you temporarily disconnect the hoses off the pressure switches and blow out the condensate line? I have had gas valves intermittantly turning on and then shutting off due to the pressure switch sensor opening up because of clogged water or clogged aluminum inducer port almost shutting off. Just yesterday someone was telling me that the gas valve was clicking and then shutting off due to the pressure switch opening and closing. Normally the hsi will not turn on if the pressure switch is open but sometimes they close long enough to get to the gas valve part of the sequence. It could however just be a spiders web on a burner orifice where you should just start a god general clean. This is very susceptible if it were an outdoor packaged heat and ac unit. Let me know how you make out. thanks You might want to check some more videos out in the furnace troubleshooting playlist- kzbin.info/aero/PLxnHR5_D2ojyN6VClLntbM4X82Gc9Xs8A

[@Bink144]

I finally got back to finish the furnace and no sir its an old 80% furnace. I pulled the burner assembly, pulled the gas jets out of the tube and the setscrews out of the top of the gas valve and blew it out. The assembly had gotten trash in it, I do thank you for your response and really enjoy your videos.

[@IshockO]

Brent Gross yeah when you get problems like that where sometimes it works sometimes it doesn't on gas furnaces just give them a full on maintenance. Clean everything, check capacitors, check filters evap coil.

[@intelin123]

My icp 80% works and runs for 5 minutes then flame goes turns off but blower and inducer stays on then quickly fires righ up then runs fine

[@joeltorres957]

Why does the pilot stay on at all times on mine? And when I get a heat call the main gas does not come on but if I remove the surface ignitor/flame sensor prong the main gas opens and it starts heating

[@tychodancer]

A pilot that stays on all the time sounds like a "standing pilot" system. is there a thermocouple that the pilot heats up?

[@DAVE-tv2fs]

@@tychodancer I have the same problem. Do surface ignitors/flame sensors go bad?

[@tychodancer]

@@DAVE-tv2fs Oh yeah. The hot surface ignitors break really easily. and the flame sensors can get dirty and corroded. If you need to replace them make sure you get the right replacement. Also hot surface ignitors can go bad if they get exposed to the oils on your hand so don't touch the black sparkly part when holding it.

[@tychodancer]

@@DAVE-tv2fs You can clean a flame sensor with a scrubby sponge like "scotch brite"

[@tychodancer]

A flame may not be sensed if the unit has a bad connection to it's "case ground". so you can have a good flame sense but a bad "electrical ground" connection.

[@JDT738126]

great video as always, who makes that meter that you've been using?

[@acservicetechchannel]

Thanks JDT738126, Here is a link to the UEI DL389 Multimeter used in the video- amzn.to/2av8s3q -- ACSERVICETECH is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.

[@JDT738126]

that looks like pretty much all a HVAC tech would need in a small package huh, do you wish you bought another meter or do you like it for every test function

[@acservicetechchannel]

No I am extremely happy with this one meter and that is the same one that I have my students train with. I can figure out I am guessing 90% of the probs with it but then I need the other two tons of tools to figure out the rest and fix the systems, ha ha! I will only link items that I am extremely happy with. I had another uei meter for 11 years before and the temp started acting funny but that was it and I have been using this version for about 6 years.

[@realestateservicessaleshea99]

Great 👍🥃🍺 Stay safe. Retired keyboard super tech. Wear your safety glasses.

[@acservicetechchannel]

Thanks for the tip

[@brhanetekie7739]

I appreciate your dedication but it would be way better to use a schematic diagram while dealing with the electrical part.