I wish this video would have been here 3 years ago. I had a pressure switch go out on my furnace and after not finding any useful videos on how to diagnose or even explaining how it works I just kinda winged it. After about 3 days of calling around I finally found a place willing to sell me a PS without a service call. I changed it an furnace worked fine. Then the blower motor went out. I had done so much research on the furnace I decided to go to school and be a tech. I still like it not exactly what I expected but it's still interesting to me so im happy
What a great video...I'm experienced, have instructed before and this is a great teaching video...A darn good refresher too, for guys that don't get the hands on as much as they once did...Thanks for doing this.
Another great video! The way I explain O.L to other people is, if a Ohmmeter is connected across a closed switch, we have a complete circuit; the Ohmmeter displays the amount of resistance in Ohms. If the Ohmmeter is connected across an open switch we have an open circuit, or an Open Loop; the Ohmmeter displays O.L.
O.L. means over limit of the range your meter is set on. Not a big problem with an auto ranging meter, but if the range is manually selected all it tells you is that the resistance is higher than the top of the range. You have to set the range to megaohms and get the OL to say the switch has a high resistance consistent with being open. There are at least some furnace boards that verify the pressure switch is "open" before starting the inducer motor and will fail if they sense even 3 or 4 megaohms across the switch due to say water ingress contamination.
That FP Mano/PSwitch tester is a must have. We are only going to see more, and more condensing furnaces with multiple p swtches. It will help make the right call when your unsure.
Up here in Ontario most furnces are already 2 stage condensing models right from the new home builders. Many of the after markets will be modulating furnaces. Knowing how to tell the difference between the symptom and the root cause is important or you'll just be throwing parts at it until it works....
@@adamradley4407 Yeah from my experience this tool does nothing but help. After 15 years I'm just trying to be efficiently correct, and good tools help make that happen.
@@thatmouththo286 mine has been in service for about 4 years now. Not a winter goes by that it doesn't spend more time out of the bag thrn in. Learning how and when to use it is important. I usually teach my new techs that a failing pressure switch is usually an indication of another problem. And in a few cases it is the actual switch that has failed. This tool helps demonstrate that very well.
Probably the easiest and most complicated diagnoses in HVAC.....Cause once you figure out HOW the PS works now you have to figure out WHY its not working properly. And that can be a very deep rabbit hole!....Especially as the industry moves towards tighter tolerances of safeties
I had a nightmare call last week, we'd been out there 5 times trying to figure this out. 90% American Standard furnace with a dual port pressure switch. Basically what would happen is the pressure switch would never close, but if you unplugged the + pipe it would close. Thing is once the flames lit and got going if you plugged the + pipe in the switch would stay closed where as before it'd open again. The flame would pop and sputter at light but then run fine. Turns out the exhaust was full of sticks and twigs but I still don't understand how it only stopped the pressure switch from closing during per-ignition but not AFTER ignition. Any thoughts Craig? I'd like to learn from this experience if I can.
Great video! Question: What happens if I connect the 2 pressure switch hoses backwards? Thanks. (pressure switch looks like 2 of those you first show joined together)
About that single-port switch at 10:00 that monitors condensate overflow -- is the hose connected to the output/exhaust part of the inducer housing where pressure is HIGHER than the cabinet? Does that mean water rising from blocked trap will cover the hose and prevent that normally higher pressure from getting to the switch? About the other dual-port switch, if the positive side going to the burn chamber is blocked or completely disconnected, the furnace won't detect that and will still happily run because the difference is even greater, correct? Thanks for the great video -- it's the best I've seen on this topic...
I was troubleshooting a furnace . The flame would die out when all the doors were closed to the closet. With the doors open and the panel front cover panel off the flame would still have trouble staying on. The gas pressure look normal. 3.5 WC . The flame would cut in and out rapidly.
Has anyone ever wondered WHY most HVACR components are cheaply manufactured even though the costs are quite high? Please don’t comment that it’s the case with everything in recent history. Just imagine if Honda or Toyota manufactured furnaces and A/C units/components - would certainly be a dark day for HVACR contractors - virtually NO service calls!
I had to listen to the difference between pressure switch designs a few times to know what they have to do without referring to the control board errors.
my powervent water heater would often go into error mode because not enough vacuum could be delivered to the pressure switch, so had to recalibrate the set screw biasing the diaphragm/spring. also make sure the vacuum hose does not have a leak and the end connects are firmly sealed. fyi, a powervent water heater uses an exhaust blower to suck combustion products out of the water heater. i would have liked a naturally vented water heater to avoid the 50 watt usage of the blower and the extra complexity and cost. however the exhaust duct in my house is too long.
@@robertcherry4971 reviewing your video, i will run a plumbing snake through the outside exhaust exit to dislodge anything blocking the flow. the flow feels unobstructed. the error mode would occur every time the burner needed to activate, and would continue for a time, but eventually the burner would be enabled. WHAT WOULD CAUSE A TEMPORARY AND REPEATING FAILURE TO OPEN ERROR?
@@robertcherry4971 QUESTION: is a pressure switch valve supposed to have a bleed port in the diaphragm chamber? i "tested" the vacuum tube by sucking at one end while closing the other, it held vacuum, no leak. then i tried sucking on the tube while its other end was connected to the pressure switch and heard air being sucked in and it did not hold vacuum; bleed port? manufacturing defect? i did not plug the leak in case it was a designed feature to perhaps remove moisture or debris.
@@robertcherry4971 as an aside, my family used to have a beach house at cape may point for a few years. it was within 3 blocks of the beach and a 100 yards from the lighthouse. we noticed the beach eroding over the years and decided to sell. is the nunnery there still standing? some of its supporting stilts where within feet of high tide when we left.
The first word you used, inducer, means to create. An induced draft motor induces/creates a draft by pulling in the combustion air and forcing it through the exhaust. Technically, once the furnace is running long enough, the inducer COULD be disconnected and the draft SHOULD be established to run safely. Since the draft is usually NOT straight up, or with minimal horizontal run, the inducer is left running for safe operation.
If you like the information that you got from this, let the ads play. Get this guy paid for all the money he’s saving you. The ad is playing right now as I’m typing this.
You need to make it clear where we have negative, positive and differential pressure. Need to show exactly where that reference point, negative compare to what? positive compare to what? difference between what? why we have negative pressure there, why we have positive pressure there. redo the video
This guy is a great example of what a teacher truly is! Amazing technician as well! Such an inspiration to all connected to this trade! God Bless!
By far the best informational video on pressure switches. Thank you for speaking in Layman’s terms.
I wish this video would have been here 3 years ago. I had a pressure switch go out on my furnace and after not finding any useful videos on how to diagnose or even explaining how it works I just kinda winged it. After about 3 days of calling around I finally found a place willing to sell me a PS without a service call. I changed it an furnace worked fine. Then the blower motor went out. I had done so much research on the furnace I decided to go to school and be a tech. I still like it not exactly what I expected but it's still interesting to me so im happy
I love heating season. Great video
What a great video...I'm experienced, have instructed before and this is a great teaching video...A darn good refresher too, for guys that don't get the hands on as much as they once did...Thanks for doing this.
thank you. still the best hvac channel on you tube.
Another great video! The way I explain O.L to other people is, if a Ohmmeter is connected across a closed switch, we have a complete circuit; the Ohmmeter displays the amount of resistance in Ohms. If the Ohmmeter is connected across an open switch we have an open circuit, or an Open Loop; the Ohmmeter displays O.L.
O.L. means over limit of the range your meter is set on. Not a big problem with an auto ranging meter, but if the range is manually selected all it tells you is that the resistance is higher than the top of the range. You have to set the range to megaohms and get the OL to say the switch has a high resistance consistent with being open.
There are at least some furnace boards that verify the pressure switch is "open" before starting the inducer motor and will fail if they sense even 3 or 4 megaohms across the switch due to say water ingress contamination.
Thank you for all you do for the HVAC industry!
one of the best videos explaining about pressure switch!
Best pressure switch tutorial out there! Great job!
Ooooh Craig has one of those fancy chrome tees for his manometer. : P What a pimp.
Really excellent teaching and explanation.
You Tha man Craig! Good refresher for the upcoming heating season.
Very good video, excellent. Teaching.thanks, for your spent time on making these videos.
I really appreciate your videos. Thank you
Thanks👏 Craig for another great video I can't thank you enough keeping my mind Sharp for this cold season 🙏
Great video. Clear and concise.
AWESOME
Thanks for making this
So very helpful
That FP Mano/PSwitch tester is a must have. We are only going to see more, and more condensing furnaces with multiple p swtches. It will help make the right call when your unsure.
Up here in Ontario most furnces are already 2 stage condensing models right from the new home builders. Many of the after markets will be modulating furnaces. Knowing how to tell the difference between the symptom and the root cause is important or you'll just be throwing parts at it until it works....
@@adamradley4407 Yeah from my experience this tool does nothing but help. After 15 years I'm just trying to be efficiently correct, and good tools help make that happen.
@@thatmouththo286 mine has been in service for about 4 years now. Not a winter goes by that it doesn't spend more time out of the bag thrn in. Learning how and when to use it is important. I usually teach my new techs that a failing pressure switch is usually an indication of another problem. And in a few cases it is the actual switch that has failed. This tool helps demonstrate that very well.
@@adamradley4407 Agreed, there is more to the pressure switches in a condensing furnace than meets the eye.
so much knowledge in this video, thank you
Very good video, you make learning this stuff fun.
Always amazing
Would be great to understand pressure reduction effect in each area and why occurs?
Awesome video
Wonderful information. They do not appear to be built to last a long time?
Great tech knowledge
Probably the easiest and most complicated diagnoses in HVAC.....Cause once you figure out HOW the PS works now you have to figure out WHY its not working properly. And that can be a very deep rabbit hole!....Especially as the industry moves towards tighter tolerances of safeties
Thanks
Great videos bossman keep them coming 👍🤙
I real like your videos
Thanks for the video.
🥃🥃🍺🍺🍺🍿🎯
Stay safe.
Retired (werk'n)keyboard super tech. Wear your safety glasses!
I had a nightmare call last week, we'd been out there 5 times trying to figure this out. 90% American Standard furnace with a dual port pressure switch. Basically what would happen is the pressure switch would never close, but if you unplugged the + pipe it would close. Thing is once the flames lit and got going if you plugged the + pipe in the switch would stay closed where as before it'd open again. The flame would pop and sputter at light but then run fine.
Turns out the exhaust was full of sticks and twigs but I still don't understand how it only stopped the pressure switch from closing during per-ignition but not AFTER ignition. Any thoughts Craig? I'd like to learn from this experience if I can.
Great video! Question: What happens if I connect the 2 pressure switch hoses backwards? Thanks. (pressure switch looks like 2 of those you first show joined together)
A bro tanks great explanation 👍
About that single-port switch at 10:00 that monitors condensate overflow -- is the hose connected to the output/exhaust part of the inducer housing where pressure is HIGHER than the cabinet? Does that mean water rising from blocked trap will cover the hose and prevent that normally higher pressure from getting to the switch?
About the other dual-port switch, if the positive side going to the burn chamber is blocked or completely disconnected, the furnace won't detect that and will still happily run because the difference is even greater, correct?
Thanks for the great video -- it's the best I've seen on this topic...
can you do a video on the new "pressure transducers" that are being used on the new ultra low nox goodmans?
I was troubleshooting a furnace . The flame would die out when all the doors were closed to the closet. With the doors open and the panel front cover panel off the flame would still have trouble staying on. The gas pressure look normal. 3.5 WC . The flame would cut in and out rapidly.
runnin out of combustible air, closet?
probably bad heat exchanger.
excellent
Has anyone ever wondered WHY most HVACR components are cheaply manufactured even though the costs are quite high? Please don’t comment that it’s the case with everything in recent history. Just imagine if Honda or Toyota manufactured furnaces and A/C units/components - would certainly be a dark day for HVACR contractors - virtually NO service calls!
I had to listen to the difference between pressure switch designs a few times to know what they have to do without referring to the control board errors.
Instead of measuring resistance across the sensor would it not be better to do a loaded circuit voltage drop every time
So being non American. Why use Gas burner with AC technology, when we have reverse cycle?
Or are you Canadian, thus lower ambients?
my powervent water heater would often go into error mode because not enough vacuum could be delivered to the pressure switch, so had to recalibrate the set screw biasing the diaphragm/spring. also make sure the vacuum hose does not have a leak and the end connects are firmly sealed.
fyi, a powervent water heater uses an exhaust blower to suck combustion products out of the water heater. i would have liked a naturally vented water heater to avoid the 50 watt usage of the blower and the extra complexity and cost. however the exhaust duct in my house is too long.
It is not a great idea to adjust the switch,it is a safety.You should have located the fault that was hindering the switch from closing.
@@robertcherry4971 reviewing your video, i will run a plumbing snake through the outside exhaust exit to dislodge anything blocking the flow. the flow feels unobstructed.
the error mode would occur every time the burner needed to activate, and would continue for a time, but eventually the burner would be enabled. WHAT WOULD CAUSE A TEMPORARY AND REPEATING FAILURE TO OPEN ERROR?
@@robertcherry4971 QUESTION: is a pressure switch valve supposed to have a bleed port in the diaphragm chamber?
i "tested" the vacuum tube by sucking at one end while closing the other, it held vacuum, no leak. then i tried sucking on the tube while its other end was connected to the pressure switch and heard air being sucked in and it did not hold vacuum; bleed port? manufacturing defect? i did not plug the leak in case it was a designed feature to perhaps remove moisture or debris.
@@robertcherry4971 as an aside, my family used to have a beach house at cape may point for a few years. it was within 3 blocks of the beach and a 100 yards from the lighthouse. we noticed the beach eroding over the years and decided to sell. is the nunnery there still standing? some of its supporting stilts where within feet of high tide when we left.
why is it that sometimes there is a hose connected to condensor box and one connected to inducer
Does the positive hose that's connected to the seal chamber monitor if theres a clog or crack in the heat exchanger?
Yes
@@RockoRocko-rz7kx thanks
👍
Inducer motor pulls combustion air in? Going on 5 years of this and I did not know that.
Pulls combustion air into the flue from the heat exchanger and forces it out the home
The first word you used, inducer, means to create.
An induced draft motor induces/creates a draft by pulling in the combustion air and forcing it through the exhaust. Technically, once the furnace is running long enough, the inducer COULD be disconnected and the draft SHOULD be established to run safely.
Since the draft is usually NOT straight up, or with minimal horizontal run, the inducer is left running for safe operation.
If you like the information that you got from this, let the ads play. Get this guy paid for all the money he’s saving you.
The ad is playing right now as I’m typing this.
You need to make it clear where we have negative, positive and differential pressure. Need to show exactly where that reference point, negative compare to what? positive compare to what? difference between what? why we have negative pressure there, why we have positive pressure there. redo the video
I found that very confusing
The 24/7 hand movements urgh