You are a fantastic teacher. I was listening while my husband was watching and I understood a lot of what you were saying. I'm not an HVAC tech. I'm a middle school teacher. I liked your analogies. It made what you were trying to teach a lot easier to understand.
A microamp is a millionth of an amp 10 ( -6). Milliamp is one-thousandth of an amp. 10 ( -3 ) . Thanks for the lecture, my Goodman furnace had a dirty flame proving sensor. It, ( and the wifie) are both happy now. Oh yea, a billionth of an amp is a nanoamp 10 ( -9). I actually sat through this lecture twice, thanx. KB4ZUS.
This is absolutely fantastic material. If most of this was taught at all in school it was only a brief glance. Thank you for such a good focus on this and giving an easy way to start implementing in normal checkups. Please bring back this speaker!
I’m a U.K. based gas/heating engineer. You call them furnaces we call them boilers, our boilers are connected (for the most part) to wet radiator heating systems. For a period of my career I worked for a boiler manufacturer, we had a reoccurring fault at a customers property where the boiler would randomly shut down to ignition lock out. Various engineers had visited the property and changed gas valves, ignition leads, flame sensing leads, flame sensing probes and a control board but the problem remained. It was discovered on my visit, that the customer had an intermittent fault with the house electrical system. One of the lighting circuits would put a short to the lighting earth (ground), when that happened it would interrupt the flame rectification circuit on the boiler, problem solved. Good, informative video.
Wow I don't think I would have figured that one out! In the United States they usually have their own dedicated breaker, shouldn't that prevent such things?
Thank you for this explanation. I see someone already commented on the fact that a microamp is a millionth of an amp, not a "billionth" of an amp but let me also add that the actual peak voltage of 120VAC as measured on a True RMS voltmeter is 169.7 Volts at the peak of the sine wave. So pointing to the peak of the sine wave and calling it 120 volts may be leaving out an important concept. I enjoyed your class.
For that grounding story (too much raining from June to August at that year), could you please let us know the machines' symptoms in that story (48:54-50:05)? I just mean, when that public grounding was not sitting properly, what were the problems with those families' appliances for the users? You are a great teacher, I've watched this video again and again, I've learned much from it. Thank you!
Further questions please:At that moment (before the public grounding fixed), what machines the customers called for service? Only the air conditioners and the furnaces? What symptoms they got on the machines before they called for service please?
Thanks, Cory, for joining us. We are about to announce our fall training schedule where you can join us live and interact directly with the trainer. The schedule should be posted on our site in a few days. jacksonsystems.com/services/training_schedule. Hope to see you there.
i love the video but i do have a issue with one part ,water is not a conductor pure h2o is actually an insulator its the other products in water that makes a conductor but love the video ton of knowledge to share thank you
Great video as always. I was checking the flame sensor signal on a mid efficiency furnace. When furnace fires up the microamp was around 1.7uA. But within a couple minutes the reading started to drop from 1.7uA to 0.6uA and furnace shuts off. I've checked all grounding, changed flame rod, verified gas pressure, cleaned burners, checked all connections and wires, checked rod distance from burner. The board is sending around 110vac to rod. Can it be a bad board? Thank
Not knowing anything about HVAC I am totally lost. I have heard mention of the neg. feedback, but it really did not make any sense, well kind of. My AC/furnace was shut down a few years ago. Every year they came out and replaced 2 to 4 lbs of freon and the cap and the control switch, first year $300 second year $400 Third year I replaced the cap and control switch They put the freon on in and it was $500 And the next year I bought window units. But when the temp hit a high of 14% I tried to start up the heat. Cleaned the filters and attempted to clean the ignitor and heat sensor. But broke it and got a new one and got it installed. Still no heat. I cleaned the jets and that was a pain. All it does is run long enough to glow red then shut off if you look close for a brief moment you will see the ignitor have a blue flame around it. Looks more like the old type pilot light being lit. But it soon shuts off and it restarts again. Not sure what to do.
I would describe it as the 30 millivolts generated by heating the thermocouple that energizes a coil and thus creating magnetic field strong enough to hold the contact closed
Yeah I've found ohms testing on ignitors to be very unreliable, I don't even do it anymore. I can tell by the brightness if they're getting hot enough.
I’m pretty confused, is the flame a conductor inside the Flame rod? Or is the flame touching the orifice which is the ground? Or is the flame touching the heat exchanger metal and that’s the ground? Or is the tip of the flame sensor Arcing to the closest piece of metal inside the furnace?
I understand that the rod is getting 100 volts, but then where is that being transferred to? Through the flame or past the flame and through the tip of the rod?
In simplest terms, the flame sensor is engulfed by the fire, 100 volts goes through the rod, makes it's way through the fire, back to the metal burners (which are also engulfed in flames), to the grounding wire next to the burners, then to the circuit board/rectification. Think of the fire as a DC wire, not a flame shooting in one direction.
@@dannyg751 That's a big 4-10. Remember...everything metal on the unit is grounded. But the burners are closer to the flame sensor, and more engulfed in flame than the spud, and gas manifold....which is painted/insulated. Ground takes the path of least resistance, and the ground wire next to the burners that connects to the circuit board is copper...AKA less resistance.
is it a fact that the 120 volts sinewave goes up to 170 volts and down to - 170 ( 1.41 is the square root of 2) and that 220 volts peaks at 311 volts? it's that the 110 and the 220 are RMS volts, NOT peak volts; careful, the peak volts are the ones that shock you !!! now back to the video; an excellent video by the way!!! thanks
RMS is effectively the average voltage since we go from peak to zero voltage. Any ac voltage, even 24 vac can shock you. A lot depends on your conductivity which changes if your skin is moist.
@ 36:20, you said "if you get hit by 5 amps, a heavy load, it would knock you across the floor, it hurts"...lol...God help you if you got hit by 5 amps because it could take less than about 1% of that to stop your heart and kill you. Due to the resistance of your body however, it would take a very high voltage (that math you also show) to allow that 5 amps to pass through your body, that's where the puddle of water comes in. Also, mA are thousandths of an amp and uA are millionths of an amp, not millionths and billionths as stated @ 36:32 thru 36:38. But otherwise, good info and thank you for providing it.
Correct on the ma (1,000s) and ua (1,000,000s). Nevertheless ua's are very small. Most meters are not good enough to read it. The resistance of the body (technically impedance when talking ac voltages) varies dramatically depending how moist your skin is and where two points of your body are touching ground or another part of the circuit. Ever notice how birds can sit on 14,000 volt high voltage lines? They are not touching a ground or other part of the power distribution system. As a result they are not shocked.
I really do not like analogies for electrical processes. I like to cover basic electrical principles and then just use that to explain the process. Why is that so difficult? That shotgun analogy was so incredibly useless compared to the actual explanation using electrical vernacular.
Jackson Systems would have hundreds of thousands more views if the production focused on the slides rather than the speaker for technical subjects like this. The content is some of the best. Direct powerpoint capture with a speaker inset except when the slides are not the current focus.
You are a fantastic teacher. I was listening while my husband was watching and I understood a lot of what you were saying. I'm not an HVAC tech. I'm a middle school teacher. I liked your analogies. It made what you were trying to teach a lot easier to understand.
We're so glad you enjoyed the session! Thank you for the feedback, have a good day!
A microamp is a millionth of an amp 10 ( -6). Milliamp is one-thousandth of an amp. 10 ( -3 ) . Thanks for the lecture, my Goodman furnace had a dirty flame proving sensor. It, ( and the wifie) are both happy now. Oh yea, a billionth of an amp is a nanoamp 10 ( -9). I actually sat through this lecture twice, thanx. KB4ZUS.
This is absolutely fantastic material. If most of this was taught at all in school it was only a brief glance. Thank you for such a good focus on this and giving an easy way to start implementing in normal checkups. Please bring back this speaker!
Yes Fantastic!
best break down I ever seen or heard. the big picture down to mico picture. darn good.
YES!!!!!!!!
I’m a U.K. based gas/heating engineer. You call them furnaces we call them boilers, our boilers are connected (for the most part) to wet radiator heating systems. For a period of my career I worked for a boiler manufacturer, we had a reoccurring fault at a customers property where the boiler would randomly shut down to ignition lock out. Various engineers had visited the property and changed gas valves, ignition leads, flame sensing leads, flame sensing probes and a control board but the problem remained. It was discovered on my visit, that the customer had an intermittent fault with the house electrical system. One of the lighting circuits would put a short to the lighting earth (ground), when that happened it would interrupt the flame rectification circuit on the boiler, problem solved. Good, informative video.
Wow I don't think I would have figured that one out! In the United States they usually have their own dedicated breaker, shouldn't that prevent such things?
In the states we don't boil air, only water
@@isonlynameleft Poor grounding system in the house.
Furnace= Forced hot air
Boiler=Hydronic system
Thank you for this explanation. I see someone already commented on the fact that a microamp is a millionth of an amp, not a "billionth" of an amp but let me also add that the actual peak voltage of 120VAC as measured on a True RMS voltmeter is 169.7 Volts at the peak of the sine wave. So pointing to the peak of the sine wave and calling it 120 volts may be leaving out an important concept. I enjoyed your class.
Great talk. Clear and informative. I wish all instructors had this level of knowledge and interest in their topics.
Awesome class.
Glad you liked it! We are adding more free trainings on: jacksonsystems.com/trainings/ Check out the On Demand section if you want to learn more!
For that grounding story (too much raining from June to August at that year), could you please let us know the machines' symptoms in that story (48:54-50:05)? I just mean, when that public grounding was not sitting properly, what were the problems with those families' appliances for the users?
You are a great teacher, I've watched this video again and again, I've learned much from it. Thank you!
Further questions please:At that moment (before the public grounding fixed), what machines the customers called for service? Only the air conditioners and the furnaces? What symptoms they got on the machines before they called for service please?
Great video, my only question is in the given example of the boss kicking the furnace fix the bad ground?
Yeah that was nice class Help a lot
i'm stunned .one word WOW!
This was a great lesson, ty for sharing
Thanks, Cory, for joining us. We are about to announce our fall training schedule where you can join us live and interact directly with the trainer. The schedule should be posted on our site in a few days. jacksonsystems.com/services/training_schedule. Hope to see you there.
just one note:
a micro amp is a millionth of an amp, not a billionth
Phenomenal. Great talk and great information. Thank you!
Very great info! Only little snafu was milli-one thousandth and micro-one millionth vs one millionth and one billionth
Love it. Thank you.
Glad you enjoyed it!
Great video well explanation about flame rectification polarity and how to be a better service tech
i love the video but i do have a issue with one part ,water is not a conductor pure h2o is actually an insulator its the other products in water that makes a conductor but love the video ton of knowledge to share thank you
Great video as always. I was checking the flame sensor signal on a mid efficiency furnace. When furnace fires up the microamp was around 1.7uA. But within a couple minutes the reading started to drop from 1.7uA to 0.6uA and furnace shuts off. I've checked all grounding, changed flame rod, verified gas pressure, cleaned burners, checked all connections and wires, checked rod distance from burner. The board is sending around 110vac to rod. Can it be a bad board? Thank
This is a Gem! Great information.
Weird ass analogy with the shot gun and the pellets ngl 🤣 but I guess I got the point
very good informative video, thanks
Enjoyed the lecture, just to raise a point, as far as I am aware Ionization is the reason electricity can be conducted through a flame.
Not knowing anything about HVAC I am totally lost. I have heard mention of the neg. feedback, but it really did not make any sense, well kind of. My AC/furnace was shut down a few years ago. Every year they came out and replaced 2 to 4 lbs of freon and the cap and the control switch, first year $300 second year $400 Third year I replaced the cap and control switch They put the freon on in and it was $500 And the next year I bought window units. But when the temp hit a high of 14% I tried to start up the heat. Cleaned the filters and attempted to clean the ignitor and heat sensor. But broke it and got a new one and got it installed. Still no heat. I cleaned the jets and that was a pain. All it does is run long enough to glow red then shut off if you look close for a brief moment you will see the ignitor have a blue flame around it. Looks more like the old type pilot light being lit. But it soon shuts off and it restarts again. Not sure what to do.
谢谢 真是受益匪浅‘
Great video, info. Thanks Well done.
I would describe it as the 30 millivolts generated by heating the thermocouple that energizes a coil and thus creating magnetic field strong enough to hold the contact closed
Water, which is made of hydrogen and oxygen, is not conductive of electricity. (( 27:55 ))
I believe the only reason water conducts electricity is the minerals in the water
Yeah I've found ohms testing on ignitors to be very unreliable, I don't even do it anymore. I can tell by the brightness if they're getting hot enough.
I’m pretty confused, is the flame a conductor inside the Flame rod? Or is the flame touching the orifice which is the ground? Or is the flame touching the heat exchanger metal and that’s the ground? Or is the tip of the flame sensor Arcing to the closest piece of metal inside the furnace?
I understand that the rod is getting 100 volts, but then where is that being transferred to? Through the flame or past the flame and through the tip of the rod?
In simplest terms, the flame sensor is engulfed by the fire, 100 volts goes through the rod, makes it's way through the fire, back to the metal burners (which are also engulfed in flames), to the grounding wire next to the burners, then to the circuit board/rectification. Think of the fire as a DC wire, not a flame shooting in one direction.
@@TheMaster5150 Ohhhhhhh Got it!!! Thanks! It goes through the Burners
@@dannyg751 That's a big 4-10. Remember...everything metal on the unit is grounded. But the burners are closer to the flame sensor, and more engulfed in flame than the spud, and gas manifold....which is painted/insulated. Ground takes the path of least resistance, and the ground wire next to the burners that connects to the circuit board is copper...AKA less resistance.
is it a fact that the 120 volts sinewave goes up to 170 volts and down to - 170 ( 1.41 is the square root of 2)
and that 220 volts peaks at 311 volts?
it's that the 110 and the 220 are RMS volts, NOT peak volts;
careful, the peak volts are the ones that shock you !!!
now back to the video; an excellent video by the way!!! thanks
Was hoping someone would have said this on the comments, Peak is different than RSM which is what your meter reads
RMS is effectively the average voltage since we go from peak to zero voltage. Any ac voltage, even 24 vac can shock you. A lot depends on your conductivity which changes if your skin is moist.
A microamp is a millionth of an amp. A milliamp is a thousant of an amp.
If you replace every part that could go bad you'll be putting a new furnace in at every call !
@ 36:20, you said "if you get hit by 5 amps, a heavy load, it would knock you across the floor, it hurts"...lol...God help you if you got hit by 5 amps because it could take less than about 1% of that to stop your heart and kill you. Due to the resistance of your body however, it would take a very high voltage (that math you also show) to allow that 5 amps to pass through your body, that's where the puddle of water comes in. Also, mA are thousandths of an amp and uA are millionths of an amp, not millionths and billionths as stated @ 36:32 thru 36:38. But otherwise, good info and thank you for providing it.
Correct on the ma (1,000s) and ua (1,000,000s). Nevertheless ua's are very small. Most meters are not good enough to read it. The resistance of the body (technically impedance when talking ac voltages) varies dramatically depending how moist your skin is and where two points of your body are touching ground or another part of the circuit. Ever notice how birds can sit on 14,000 volt high voltage lines? They are not touching a ground or other part of the power distribution system. As a result they are not shocked.
I really do not like analogies for electrical processes. I like to cover basic electrical principles and then just use that to explain the process. Why is that so difficult? That shotgun analogy was so incredibly useless compared to the actual explanation using electrical vernacular.
Fire the person running the camera. Focus on the slide. Just zoom out please!!!
Jackson Systems would have hundreds of thousands more views if the production focused on the slides rather than the speaker for technical subjects like this. The content is some of the best. Direct powerpoint capture with a speaker inset except when the slides are not the current focus.
There is so much wrong with this presentation, it’s mind boggling.
I thinks he had some good info but there is a lot he’s wrong on.
You guys care to point them out?
. Flame is out of control.