Gas Furnace Spark Ignition Control Troubleshooting!

[@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.

[@fredfred7361]

Wwzx

[@jimv3352]

Mine will ignite but as soon as the pilot light is lit, I hear a click in the control board and everything shuts off. Then it clicks again and the whole process starts over. But as soon as I have a pilot flame, everything shuts off again.

[@jessec7821]

I am by no means an HVAC guy but am mechanical and this is how every video should be.. straight to the point, all setup, and no shaking camera. 12/10, I wish every video followed this format

[@gdmedic4346]

i am not a math professor by trade, but 12/10 is not good math.

[@Bilmor1982]

Sir you are extremely gifted at teaching! You make everything so clear and practical I’m sure you are a walking encyclopedia but you watered everything down so good but yet very substantial! God bless you sir!!!

[@jotermoter]

Thanks. 6 years later and you are still helping people! Used this for my Raypak pool heater troubleshooting.

[@INLANDEMPIREKING]

incredible explanation. You sir are a great teacher

[@acservicetechchannel]

Thank you very much caliguy909!

[@emiliosanjim5874]

Yo estoy bien triste , tengo un horno de panadería y creo y supongo está dañado l módulo de ignición es un RAM4 de robertshaw y no logro encontrarlo PR muy interesante tu video

[@bawlout9367]

ran into one of these in the field , before seeing this video your trouble shooting and refresher videos helped me isolate this part as the issue. thanks again for the extra insight

[@lupine617]

Truly splendid explanation and awesome demonstration on trouble shooting this system, and all the units involved...

[@solweiss554]

Very simple and thorough to the point. Practical without a lot of chatter.

[@acservicetechchannel]

Thanks Sol!

[@petebacher]

THANK YOU! My Raypak pool heater has this setup and none of the Raypak manuals provide any details on how it works. Your video was EXACTLY what I needed to understand this setup so I can effectively troubleshoot it. Thanks for taking the time to make and post this great tutorial! -Pete

[@acservicetechchannel]

Glad to help Pete!

[@jasonley1529]

Great video! Curious how long the pilot should stay lit while it’s proving the flame. pilot lights, but goes out within a second... sometimes the main burner will light, but sometimes it doesn’t and then the pilot just cycles every few seconds... your video is the best explanation of the controller I’ve seen, but haven’t seen anywhere how long PV is supposed to stay open to prove the flame

[@blazeeisner9620]

Thank you,again. It's Blaze. I cleaned up my ground to my unit chassis and replaced the flame sensing rod. When I energized the unit I had the same problem. One thing that I didn't notice was that the burner that had the sensing rod going to it was not lit. I removed the burner and pulled out the orfice and there was spider webbing inside the back of it and plugging up the opening. I cleaned it out with my tip cleaner for my oxyacetylene rig and returned it back to service. The unit is heating properly at this time. Thank you for your videos Blaze

[@acservicetechchannel]

That's great to hear Blaze!

[@mdwilliams3824]

I agree another good video. Had this happen just last month, after verifying continuity through the safety loop I determined that the spark ignition bracket had heavy corrosion between it and the main chassis. Just a little sanding of both matting areas was all it took to get it going. Looking forward to your next video.

[@acservicetechchannel]

That's awesome to hear, good job!

[@ThomasWalker-m2y]

Very good explanation with actually seeing how it works.

[@johnrutkowski5929]

I'm going to grab my multi-meter and start testing for spark. Thx for explaining how the system works.

[@hvacguy11]

Thee absolute best HVAC instructional videos on the internet. Hands down!!

[@acservicetechchannel]

Wow, thanks!

[@jmead6121]

Thanks Great explanation on Spark Ignition 25 yr in & ive always struggled bc i rarely run into thees type ignitions 7 i seem to forget & have to start over almost ... but Now its so crystal clear & with my notes taken on phone i soon Not forget again lol Thanks Again for this & all uR Videos for ive been watching You for many years Now Tks xxx jerry

[@liberaltearsaredrowningme7049]

Thorough, concise explanation. Very much appreciated.

[@acservicetechchannel]

Thanks a lot, always appreciate your comments!

[@jm-handyman7878]

I like your nickname!😁

[@bassir2002]

Just don't know how to thank you enough for this very informative video.

[@acservicetechchannel]

Thanks Bassir2002 for any support- patreon.com/acservicetech

[@robgullett9379]

Very good to-the-point, clear and concise explanation... great job!

[@acservicetechchannel]

Thanks Rob!

[@mikeeames8463]

The best tutorial I have seen on this subject. Thank you!

[@acservicetechchannel]

Thank you very much Mike Eames! I appreciate that!

[@fastxsam]

Thank you for this video very informative. I used this information to diagnose a faulty igniting module for a customer.

[@guitarhvac]

Excellent explanation. Great refresher going from cooling back to heating season!

[@acservicetechchannel]

Glad it was helpful!

[@retiredguyworking8057]

Excellent description of the operation. Having a second try turn on at times. Checking ground first. Thank you for giving me a place to start. Hopefully not the module!

[@phillipwoods5874]

Great job, iv'e learned more about the subject of furnace flame rectification from your three videos than i did in class. The grounding was never explained.I guess that's what you get from mostly book learning vs visual or hands on.

[@acservicetechchannel]

Thanks Phillip Woods, yeah you need to teach in front of live equipment while explaining the subject with maybe a study guide to help. Thanks and nice image!

[@dustinthewind5538]

Thank you for this video. Just had a no heat call on a lennox whisper heat with very similar set up this morning. Makes much more sense to me now after watching this.

[@acservicetechchannel]

That is awesome to hear Dustin!

[@sirsmart1]

very good explanation ,,, step by step

[@acservicetechchannel]

Thank you so much 🙂

[@lancerudy6584]

Thanks for great video. Helps 100,000 BTU.

[@albotiger7268]

You are a great teacher! God bless you!

[@michaelcostello6991]

This was amazing video. Thank you. One of the best videos out there. You really nailed it.

[@acservicetechchannel]

Wow, thank you!

[@rocker8692]

You are my new teacher now lol.I didn't pay attention in AC school.Excellent vid.

[@acservicetechchannel]

Thanks Chad!

[@TheRealDegen100]

This is exactly what I needed

[@jasona9231]

What a great video and thank you for the clear, easy to understand explanation and demonstration. Excellent!

[@acservicetechchannel]

Thanks Jason!

[@jasona9231]

Another thing I find impressive is that you courteously take the time to thank people for their comments...perhaps each and every one, that is great! I am working on my Dunkirk natural gas boiler from 1987 and I noticed the last season or two that it would frequently keep sparking the igniter even after the pilot and the main burners were lit. This year I decided to look into now that winter is on the way. This system uses "one wire" for detecting the pilot, not a separate flame sensor like on most modern models. The igniter rod (mostly wrapped in enamel like a spark plug just to be clear) appears that it may be a little dirty and so I would like clean it with some emery cloth but it is very difficult to reach while still attached to the center burner (3 burners total). My question is this... If I unscrew the two screws holding the iginiter assembly to the burner and bend the aluminum pilot gas tube a little toward me so I can clean the rod am I creating a safety hazard in the form of a leaky pilot gas supply tube? Will cleaning that rod even help me out, or is it likely a failing Honeywell control box? Thank you in advance! Keep up the great work. @@acservicetechchannel

[@acservicetechchannel]

Cleaning the rod should help but it may be a weak signal on the ground coming back. If it has a separate rod for the ground then yeah cleaning that too will help. We uses steel wool and not emery cloth though due to silicone residue. We usually disconnect the pilot tube and spark assembly at the gas valve and just pull the whole assembly out. Try to not move the pilot tube around too much due to a possible kink. You could also just leak test the tube with non corrosive bubble leak detector like I have at amazon.com/shop/acservicetech thanks for the note and yeah it is a lot answering everyones questions but I try, thanks

[@jasona9231]

@@acservicetechchannel Thanks for the quick reply, very good advice, and professionalism. I had not thought of that point regarding emery cloth, glad you said something. I might just have to order that leak detector you recommended. Thanks again, take care!

[@1adams1]

Great video and troubleshooting. Saved me a pile of money.

[@DrManhattan7]

First of all, EXCELLENT explanation, just wat I was looking for. Now, I still can't determine what's wrong with mine, slightly different model, but same basic functionality I have the S8610F. When the unit receives the call for heat, I get a spark, the pilot ignites, the spark stops once the pilot ignites, but no voltage passes to the MV, then pilot turns off. Then sparks starts again, turns the pilot on again and the cycle repeats. The fact that the spark stops, makes me think it's getting signal that there is flame, (why keep sparking if the pilot is already on, right?) but it's failing to pass voltage to the MV. For the grounding, I tested two things, continuity from the spark rod at te pilot to the spark terminal at the module (to test the spark wire) and it was ok. Then I tested continuity from the pilot assembly to the ground terminal at the control module, and it was good too. Any thoughts?

[@acservicetechchannel]

Sounds like it is a bad spark control module if you are getting a flame rectification signal verifying the flame, thanks

[@DrManhattan7]

AC Service Tech LLC. Thank you for the fast reply. I ordered the module, let’s see how it goes.

[@al52269]

Great video. Great teacher. The issue I'm having is no spark or flame. I replace everything but the ignition wire. I replace gas valve, Ignition Control module, pilot burner, Still not getting a flame or Ignition clicking. I believe is my ground. Will try it. Thanks for sharing your knowledge

[@acservicetechchannel]

Thanks, let me know how you make out. Do you have a strong 120v coming in while under a load and then a strong 24-28.5v?

[@al52269]

I did everything you did on your video. Still won't start. I noticed bad ignition wire. I'm going to order one as soon as I get a chance. Been working 7 days a week since February no days off unless a holiday and then I sleep during day due to I work 3rd shift. I think the Honeywell module may be bad even though it's new. After ignition wire is replace I will recheck everything again. I will let you know what my findings are. Thanks again for your help

[@acservicetechchannel]

Oh nice, ok thanks

[@guillermomartin2185]

Great video. I have the same ignition setup as here, spark lasts up to 5 minutes before pilot is lit. If I move the pilot assembly away from the mounting point and pilot will light and 24 v is sent to main valve. It has a good ground.

[@acservicetechchannel]

Is the pilot tube loose, is the flame good height after ignition? If the pilot head bent out of shape and gas not staying in the right area? thanks

[@guillermomartin2185]

AC Service Tech LLC pilot tube is indeed bent. I tried to bend it back to center with a pair of channel locks but i don’t want to break the head. Do I have to tap it out of the housing it’s in to re center it?

[@acservicetechchannel]

@@guillermomartin2185 It has a compression ring so once you undo the brass nut, the tube with compression ring would come out of the head. You would reround it with an adjustable wrench which has a flat surface turning back and forth on the outside diameter, thanks

[@guillermomartin2185]

AC Service Tech LLC done. I reinstalled it and it does the same thing. It Seems like the inducer motor draft prevents the pilot from kicking on.

[@101Parkside]

@@guillermomartin2185 Hi, this is old news to you now since your question was 3 years ago. I'm having an issue with my furnace as well and while going through this thread I noticed you were talking about bending the head of your pilot burner to center it. In researching my issue, it seems to me that they make these pilot assemblies with a left of center or a right of center (and perhaps centered) pilot burner. I think that is, so the pilot flame burns toward the spark and sensor rod as well as angled toward the burner in order to ignite the flame. Whether left or right would depend on which side of a burner the pilot assembly was attached to. I'm not a tech but I think that seems to be the way they are. How did you make out?

[@chuckjones5987]

Excellent breakdown of how this system works. Well done Sir!

[@acservicetechchannel]

Thanks Chuck!

[@TheStudpop]

Just wanted to correct you on something you say here and in other videos. While it is true that the module detects the presence of a flame by passing a current through the flame-it is not detected by measuring current through the ground wire. Since all grounds are tied together, both with wires and by the metal chassis, there’s no way to measure ground current since there are multiple paths. It can only be measured on the “hot” side, meaning the current that’s flowing through the sensor wire. There’s probably an internal resistor in series with the sensor wire and the voltage drop across the resistor is directly proportional to the current.

[@dukerob1973]

I hope you teach at your local jr college or tech school. You were made to teach man.👍🏻👍🏻

[@jredbokie1247]

Thank you so much this helped me tremendously.

[@whitesheatingairappliancer7101]

Great video. I have tried in the pass to run a continuity test on the high voltage wire unplugged from everything else. I could never get a reading?

[@spartan5106]

That was a very technical video

[@blazeeisner9620]

Thank you for your videos. I just looked at the video regarding flame rectification and I think that I should look at my flame sensing rod along with my burner and the ground. Thank you again Blaze

[@acservicetechchannel]

Let me know how you make out! Thanks

[@jeeperguy4290]

Awesome video. I had a job today where the spark wasn’t occurring all the time, I was turning off and on the power to the unit until it sparked, pilot gas was lit & rectified. Burner came on followed by the blower. I’m not a hvac tech but a gas utility worker who does safety checks. Didn’t think to check the ground but sounds like that might have been the issue? What do you think? I would toggle the switch back and forth until the spark occurred and it was fine after that. I could hear the hum of the xfrmr so I don’t think it was service disconnect switch.

[@tommulcrone182]

Once again thank you very much. You're the best

[@acservicetechchannel]

Thank you! I hope you enjoyed the video!

[@GeminiSeven43]

Could you show the milliamp testing like you did for the dual rod flame and show what the milliamp reading should be for this Honeywell unit?

[@vernroach3413]

Always worth watching your videos...Thanks again.

[@acservicetechchannel]

Thanks Vern!

[@jaysingh-ho7eb]

Excellent explanation. Thank you

[@jorgeortega1413]

excellent explanation ,so clear ,so easy to understand great job ,great pro

[@acservicetechchannel]

Thanks Jorge!

[@xenghuong]

Really informative! Thanks for the video.

[@acservicetechchannel]

Glad you enjoyed it!

[@Realrhod]

Really good useful video. Thanks

[@analysispros]

Thanks for your video - very good! I have an old Lennox G12 Furnace with a G60QHL interment ignition - I get a spark from the controller but its only for 35 seconds. I think you mentioned it should go for 90 or so. After 35 Seconds I hear a click and I think the controller shuts the pilot gas. I do smell gas so I know there is flow to the pilot during that time. My first question is - do you think the G60 controller went bad (its the original I think from 1980). My second question is - can that controller be replaces with a more modern one - if so which one to get? Thanks in Advance!

[@szcz546]

Thank you for this video

[@acservicetechchannel]

My pleasure

[@leejagin7979]

Very helpful

[@acservicetechchannel]

Glad to hear that

[@gpsperez5193]

Thank you for the video im having the same problem my module is a ruud rheem 780-715 u no spark no pilot it has only 24 volts is that enough volts?thanks

[@michaeldower4335]

Great explanation and demonstration.

[@acservicetechchannel]

Thanks Michael!

[@franciscoflores2718]

Can you make a video on how to install the pilot silver tube.. or on what tool you use to straighten the pilot silver tube? I always have trouble getting the pilot silver tube straight enough

[@jasonjokiel7188]

Awesome video

[@zhenjiang4776]

Great video, I have the same issue, the pilot is on, but no main output, I check the ground is ok, the main output is always 0v.

[@acservicetechchannel]

Disconnect the power and disconnect the ground then take a resistance reading from the pilot head to the end of the ground to see if the resistance reading is high, thanks

[@TheRealDegen100]

Great video. Only thing I think would have helped is if you added the gas valve into the sequence

[@Protek1]

Excellent presentation.

[@acservicetechchannel]

Thanks Craig!

[@backho12]

This guy is a genius! Thanks for the explanation!!!!

[@acservicetechchannel]

Thanks Backho12

[@UltraHydrophobiccoat]

Merry Christmas and Happy New Year ! Will the ground affect low voltage input? I have a Honeywell S8610U spark ignitor control which burned the low voltage transformer. I replaced the transformer, and turned it on. Then I got 8 flash error code on this control, which means the low voltage input has problem per instruction. I checked the low voltage input wire (to TH-W) and found it is grounded. When I pull off the burner ground wire (GND), the low voltage wire does not ground any more. Does this mean the ignitor control is bad? Thank you.

[@101Parkside]

Great video and explanation of steps and stages. I hope you can help me. I have this same setup, but the only difference is that I have a Honeywell S8600M Module that has all the terminals on one side as opposed to yours which has them on both. All the steps have been satisfied just as you have explained. I have spark, I have pilot light, I have 26.4 volts from the transformer to the module, I have 26.4 volts from PV to MV/PV and I have 26.4 volts from MV to MV/PV going to the gas valve. As soon as I turn the furnace on, I get spark and the pilot lights, I hear the gas valve click open but here's the PROBLEM ... the burners will not ignite. What are the next steps to try and diagnose? What is preventing gas from going to the burners to get ignited by the pilot light that is on and seems to have good coverage across the sensor rod? I live in Vancouver, so the furnace sits for 8 months unused and of course when a guy needs heat, that's when we end up with a problem. Hope you can help! (Edit: I should have mentioned that I also cleaned the spark/sensor rod with steel wool even though it looked good beforehand). Thank you!

[@BuffaloFranimal]

If you have 26 volts from my to mv/pv at the gas valve terminals it should open. After sitting for 8 months sometimes the valve sticks. If you give it a lil rap with a back [f a screwdriver it may open and work normally. If not check the resistance of the gas valve coil. It should be between 8-12 ohms otherwise it is likely open or shorted.

[@101Parkside]

@@BuffaloFranimal Thank you for your reply. I did try lightly tapping the gas valve but other vids also discourage that. As I mentioned, you can hear the valve click in sequence as though it's opening but as you say perhaps something isn't opening as it should. I will check out the ohms as well. I appreciate you taking the time to help. Cheers!

[@jamesrockford5145]

Great instructor! my instructor has students intimidated to ask questions.

[@acservicetechchannel]

Ha ha that's weird. When people ask questions, it only makes the instructor better. We realize we have a limited knowledge and we need to think deeper or get ourselves into different experiences to eventually be confidant in answering that segment of questioning, thanks

[@jamesrockford5145]

Can't wait to leave that class!!! Keep up the excellent productions.

[@acservicetechchannel]

Thanks James!

[@chandarasena]

Thank you very much, the explanation is very good.

[@acservicetechchannel]

Thank you!

[@chili302]

Thanks for the insightful video. I have a unique problem appears very strange. My furnace will go through the initial ignition and main valve opens for about 10-15 seconds or so with full flame, appears to be OK, than suddenly both the pilot and main valves shut down for some unknown reason. It then start ignition and the valves open with nice flame again followed by sudden shut down. These crazy events repeat about 3 to 4 times until the flame limit switch shut down the whole furnace. My local HVAC tech replaced the valve, the ignition module but still unable to resolve this problem. Any idea or suggestions for me to further trouble shooting. Thank you in advance for your help

[@lijoima]

Great video as always. Having an issue with my single rod honeywell system. New pilot assy installed. Pilot not igniting by occuring spark however will ignite with a lighter. When pilot lit spark continues and no opening of MV. I'm unsure what could be causing both!

[@ChrisV-]

Good video, definitely will help when troubleshooting.

[@acservicetechchannel]

Thanks ChrisHvac!

[@EnjoyCalculus]

During the flame rectification process in this setup, what part is the flame rod that is sending AC voltage to be rectified? How do you test its getting voltage

[@tmoua743]

Great video! The issue i'm having is, my burner turn on but after 5 mins of running they turn off and the pilot reignites, run a few second and turns off. Fan limit stays at about 150-170 degree so its not overheating to shut off. Tested MV to Common and only reads 13 volts. Is the flame rod bad at this point?

[@mikepotter3802]

If there is a spark, but no flame what is likely the problem? I am editing this to include that I also would like to know when checking for 24V on the MV/PV to PV does it have to be during the spark attempt? Will there be a voltage after it gives up for about 5 minutes?

[@Juegosdecartas101]

Very good explanation I'm learning 👍

[@acservicetechchannel]

I'm glad you appreciate it, thanks!

[@EurekaRecycler]

Hi, can you do a video on where all the wires on this module go and what each wire does? Are most of these modules interchangeable? Thank you

[@ronlamb-strategy2execution110]

This is by far the best explanation I've seen. Many thanks. I'd ask if there is a way to differentiate the problem, if you do get pilot flame going, but the main gas valve doesn't turn on. That is, since I don't get an MV voltage after pilot. Can I jump temporarily, 24 V to the MV line or disconnect the wires going to the MV connector, and give those wires 24v to see if the main valve will open and provide gas? Otherwise, I don't know if I have to order the Controller alone (no MV problem), or whether I also need to replace the main gas valve. It would be good to have a way to prove the value good / bad separate from the controller. Any procedure for this would be appreciated.

[@101Parkside]

Hi Ron, did you happen to fix your problem on your own or did you end up getting a furnace repair person in? What was the problem? If you see my question at or near the top of the comment section, it looks as though we both have the same issue? Look forward to hearing what it was. Cheers

[@ronaldlamb9766]

@@101Parkside funny to get this, as I did replace the controller and got it working myself, but shocked to find yesterday, that nothing working again. Blower yes, but no pilot, not attempt at starting, and no lights on the little LED's that are now standard on these controllers. I wish I remembered everything that I learned. Feels like I'm starting over :(

[@litesp]

I have a mid-90s Carrier 58GSC upflow furnace. Last year, I had to cycle the power several times to turn the furnace. These last 2 months power cycling doesn't do anything. I changed out the control board without any success. I get 28V going to the Ignition control, but nothing happens. I don't get any spark or pilot gas flow. Should I clean the electrode first or just replace the Ignition control?

[@jeanpaulremond3076]

Hello great video. I have an old equipment from Sears, an 867.762360, it works but some times while running the flame just dies and then it starts the pilot again and lights on, then the flame dies again and repeats the whole process again, sometimes 4 or 5 times and then stays on until reaching temp. Could ground wire seems ok, where should i look pls ? I am a home owner not a tech. Thanks.

[@bryandellinger2263]

Excellent explanation, I was working on a high voltage furnace ignition module 120 volts. the furnace would stay on for about 1 or 2 hours then the ignition module would fail and would work as you tapped it with screw driver is there something wrong with ignitor module ?

[@acservicetechchannel]

Possibly, did you check the ground wire and connection, as well as take the connectors off, crimp them down and put them back on? Is the flame sensor steel wooled for a good signal strength?

[@dennismphotographer]

How do you determine if the spark rod is good or bad? New box but no spark....

[@yroncekenold878]

You're so good

[@alacran1986]

Can you explain lockout? I get 24V to the board but nothing to the gas valve PV and MV. After a reset everything works fine.

[@thedeekan]

6000 volts? Not milivolts? If you were to hook up a multimeter to the spark cable and ground, what should the reading be? DC right? I’m getting 6.1/5.8/6.3 readings when spark is initiated.

[@playmusic972]

well explained

[@KB-wq5bb]

Question? I was told by a plumber on the tankless hot water heaters to not use anything but a dollar bill to sand. Have you heard this or know if true. Thanks.

[@mrxmrp8795]

Hi, I have a furnace with the honeywell s86h intermittent pilot 100% shutoff which is what I thing you are explaining here. My problem is that the blower motor won't shut off. The tech came out and did some trouble shooting and says the s86h module is the problem. Could this module cause the blower motor to run constantly? I'm trying to educate myself. Thanks.

[@alanhelm2413]

with excellent info from you i was able to get the boiler working but now the pilot lights -mv does not open and reads 14 volts any idea?

[@1weirddoe571]

The sparker is also a sensor? Have a video on this "flame rectifier"? Also, why have a pilot since power-vent water heaters don't or do they?

[@justinbayne4915]

I am having a problem with the newer model of this board the s8610u . I am getting spark and pilot but no 24v to mv .we have checked all of the grounds. In this particular unit, the only way to prove the flame is on the ignition board, with this ignition board it has a jumper that you disconnect and hook a flame sensor to. We have tried cleaning the flame sensor and still nothing. Also we will replace the board and it will work for a week or two and then for some reason will not sense flame again. Need your help guru !!

[@aifrisyad7491]

how about the flame censor, do you have a video about the whole system (gas valve, module control, blower fan, flame censor and burner with ground wiring), thanks anyway

[@paulp757]

Outstanding. Very informative and well done!

[@minark4137]

Thank you for the info! However I am still having issues with my main burners not igniting. I turn the thermostat for heat, the inducer comes on along with the pilot and thats about it. The main burners never ignite even when I'm reading 26.5v at the MV & MV/PV terminals. Do you think it's the gas control valve?

[@acservicetechchannel]

Or the gas pressure. Check for 26.5v actually on the valve too. I have also seen cobwebs over the gas orifices as well preventing the gas from coming out in the right direction.

[@thesteveprichard]

you the best I've ever heard!

[@acservicetechchannel]

Glad to help Steve!

[@RC-Heli835]

i have that same model in my furnace. Does this thing shut the pilot back off in a certain amount of time if the main gas valve does not come on? A family AC tech was telling me that if it did not shut the pilot off when the main valve fails to light the burner that the pilot sensor is the problem. I tried a new one and it still does not work. I checked ground and all that with a continuity test and all checked out fine. Mine was not shutting off the pilot by the way after any amount of time.

[@realuniversechannel1]

Good job explaining how it works. I have a Utica boiler model PEG150BIDE with a VR8204A gas valve and a S8600M Honeywell control. I have a spark and a flame that lasts for a second and turns off and again a spark followed by a flame that lasts like a second, and it goes on and on, but no steady flame, is it a bad gas valve?

[@acservicetechchannel]

Make sure to check your gnd wire, clean the ground where the flame touches the metal and brings the voltage from the rod to the metal nearby. Check to make sure that your pilot tube is tight as this also may be part of the ground. In reference to the gas valve, you can check if you are getting and then loosing the 24v signal from the ignition control thanks. It is likely a ground problem not proving the flame, thanks

[@realuniversechannel1]

That's not necessary, I bought a new S86, as you suggested, and it works, you know what you are talking about, you are good at that man, thanks a lot and have a nice and happy thanksgiving with your family!

[@realuniversechannel1]

One more question: that unit has a Safgard model VXT-24 automatic feeder with two wires coming from it (one white and the other orange), where those two wires are connected?

[@nybiggs]

My 4 year old Weil Mclain boiler started exhibiting intermittent problems which first started in Christmas but seems to be happening more often. After the call for heat, I hear the pilot light, but the gas doesn't open and the burner never ignites. After a little while, the pilot will shut itself off, and the boiler is then locked out for good until I completely cycle power to the boiler. The issue is that this doesn't happen very often. Boiler runs fine for a week or two and then I get a call that there's no heat in the building. Calling a professional over, they see the boiler running and say they can't do anything.

[@MrMultitool]

Great Demonstration!

[@acservicetechchannel]

Thanks TP Services!

[@michaelcostello6991]

Is the 24 volt polarity important ? The supply to the controller . Its 24 VAC

[@gyver471]

Damn what a great explanation

[@williambelfield4661]

great vid

[@acservicetechchannel]

Thanks a lot William!

[@JEFFREYHVAC12]

very good info thanks for taking time for us youtubers

[@acservicetechchannel]

Thanks Jeffrey!

[@melvin292]

excellent, excellent video!

[@acservicetechchannel]

Thanks!