Lennox Prodigy Playing Games RTU Not Cooling

[@Boodieman72]

Had a local tech come out to do an AC check on my home. Somehow they managed to short or do something that killed both the circuit board and the wall thermostat. Nice to see a real professional at work.

[@HVACRSurvival]

That really sucks, sorry to hear that! Thanks for checking out the video!

[@TheGhettoLobster]

They hooked up the high voltage to the low voltage on the contactor

[@matthewrichardson2467]

Hey Rick, Love your methodical troubleshooting approach, and your take the previous guys assessment with a pinch of salt and you confirm things for yourself.

[@johnstrh1]

any other newer guys like me watching, what he said about looking at the temps not the pressures is what really helped me a while ago. when you see 5 or 6 different refrigerants in a day going by temp is so much easier

[@HVACRSurvival]

Preach it 🙌

[@HVACRSurvival]

@Brooks.Mechanical.Electric It just clicked for me early on. It’s amazing how much you hear about pressure when listening to others.

[@HVACRSurvival]

@Brooks.Mechanical.Electric you can find it online if you search for geothermal suppliers I was able to get mine at my carrier supply house. Habegger Corporation is who we use.

[@jasonjohnsonHVAC]

Nicely done Rick. Condemning a board is the absolute last thing on my list, whether i originally suspected it or not. You were very detailed and methodical in your approach

[@HVACRSurvival]

Cool, thanks! I knew that control board was going to be pretty expensive so I want to be darn sure.

[@jasonjohnsonHVAC]

@HVACRSurvival and you did make sure. Too many people condemn a board without going through the proper steps.

[@timbrown9305]

Great to see "REAL" diagnosis. Fantastic !

[@HVACRSurvival]

Thanks 🙏 👍👍

[@jaymartin5095]

I had been wondering where you were. Thanks for the update. This one was interesting, eliminating everything else one by one. Then have the vendor confirm it's their board. Nice sleuthing and keeping your cool. Thanks for the education.

[@HVACRSurvival]

Thanks Jay! Yep just stupid busy

[@maintenanceman1015]

Worked on AAON units where the control board controlled a bank of relays . If a contractor went bad it couldn`t take out the main board. But had the blower short cycle ,the relay would turn on the Frequency Drive then shut off . Was the coldest day in winter ,why not think was -10 ,just pulled the relay out and reinstalled it . Good to go , Got 3 back relays just in case , 13 AAON units at that location.

[@jimfurnell7657]

Awesome diagnosis' your trouble shooting skills really make me stop and rethink of my approach to low voltage issues. Sometimes they can drive a us techs crazy. Great informative videos, stay safe.

[@HVACRSurvival]

Thanks Jim!

[@elBusDriverKC]

On those prodigy units, they have a self test mode. Pulling the wires from the thermostat connections and putting it into self test can help get thermostat problems / thermostat wiring problems out of the picture. I've seen a few go bad here and there. At $750 - $1000 it's an expensive failure. Fun part is having to reprogram the new controller for all the fancy settings.

[@gordonborsboom7460]

Satturation temps are the ssame yes...just dont forget to reset the refridgerant type on your electronic gauges. This has caused me all kinds of unnecessary grief

[@HVACRSurvival]

I know me too🤣🫶 it happens all the time

[@jasonyeager9102]

Same…was working on a walk in freezer (404) on one call and then went to a 410A AC call and was like damn this is low…good thing I noticed before going further.

[@ryanisaacson118]

Yep

[@joshua.sookoor2025l]

Good video rick from watching your videos i learn alot about these units! 🎉🎉

[@HVACRSurvival]

Thanks Josh!

[@stevencossaboon3237]

Nice troubleshooting and job Rick.

[@kingwookie7210]

lennox one of my least favorite over engineered RTU's, good work as always.

[@HVACRSurvival]

Same here!

[@Boraxo]

That Jumper King is slick. 👍

[@wd8557]

Nice, I'll have to put this one down in my book.

[@zekenzy6486]

Great video. Thank you for sharing. Have a nice weekend. I'm so happy to see you back. I see you in next video 💯

[@HVACRSurvival]

Thank you, I’m gonna try for another tomorrow but it depends on time

[@andyread4332]

Love your work Rick. Keep em coming

[@HVACRSurvival]

Than you!

[@Dalan612]

Solid troubleshooting Rick. Thanks for the upload 🤘🏼

[@HVACRSurvival]

No problem 👍

[@MariosACandRefrigeration]

It could have been a sensor or some other thing,unplug everything and reconnect until it shows a problem to isolate,also you can switch 24 volt on transformers in case that one is weak.thanks for sharing.

[@helmsajr]

Great job Rick Lennox not my favorite unit to work on but you got it figure out.

[@HVACRSurvival]

Thanks 👍

[@thesilentonevictor]

Good troubleshooting Rick

[@throttlebottle5906]

"how dare you" not release videos daily. LOL. I was ready to send search and rescue looking for the roof, rack or cooler you was stuck in. 🤣🤣🙃

[@HVACRSurvival]

🤝😅👍👍

[@LilyRoseElectric]

Great job 👏 Killing it.... always the best

[@joeyf504327]

it's probably a failed capacitor on the controller that is there to supply current during DC power draws for the computer when activating the 24VAC control relays. I have seen this happen in printers. They get stuck constantly rebooting because a capacitor fails and can't provide current during startup when there is a momentary power draw. New cap and good to go.

[@HVACRSurvival]

Lennox guy said there’s a relay that fails?

[@DanielGaytan-vl9hw]

The board has a limit on the incoming voltage, any voltage higher that 27v Ac will cause it to lock out or act like that. You need to change the primary voltage tap on the T1 and T18 transformer to lower the secondary voltage.

[@HVACRSurvival]

You would think Lennox tech services would have said something about that. He did tell me that there’s a relay inside the control that has a history of failing. 🤷‍♂️

[@AntonioMiguelAmorosCrippa]

Thanks for your videos.

[@HVACRSurvival]

Glad you like them!

[@davidpetetsen3744]

Nice video I had same issues with lennox 25 ton rtu just like that

[@HVACRSurvival]

Good to know I’m not alone

[@Eddy63]

Nice troubleshooting as usual ... Are you & Chronic gonna do any more streaming ... They were always fun ... Thx

[@HVACRSurvival]

Eventually. Crazy busy lately

[@kenebler7855]

Awesome video thanks for going through everything like you did very helpful

[@HVACRSurvival]

No problem 👍

[@tirrellboi]

Great Video! I always looking forward to each one 👍

[@HVACRSurvival]

Glad you like them! Thanks!

[@terrygrant8126]

You did good friend!....

[@HVACRSurvival]

Thank you!

[@halverde6373]

The actual problem is it's a Lennox. Similar to Trane. God help all of us that fight against chaos. Glad I made it out alive to retirement. Fond memories but I don't miss it.

[@rjeepster8640]

I would start by putting a thermostat right to the controller to find out if downstairs is causing your issue

[@Pippy626]

I love the videos. If you ever need help with editing I can assist. I wouldn’t mind a few longer videos too

[@BlackAck90]

Still trying to find out where "AcrossT" comes from.

[@jamesashley3827]

Thanks

[@HVACRSurvival]

Your welcome!

[@ceilingfanmusic6597]

So i have 2 hypophises as to whata going on with that controll bored. 1: the filter caps on the voltage ragulation circut is going out causing the MCU to be unstable to the point that any change on the power rales causes the MCU to reset. 2 one of the relays on the controller has a shorted coil ( the y1 relay) and when the controller trys energyzing the relay it pulls down the supply dc voltage for the controll bored and causes it to restart. Pardon my bad spelling

[@HVACRSurvival]

Lennox tech service told me that there’s a relay inside there that has gone bad so you might be correct

[@knockitofff]

0:34 that's a sheave LOL

[@HVACRSurvival]

Whatever🤫 you knew what I meant. 😆

[@DeepThinker202]

I have a question do you service residential units and can you upgrade ine half of an ac system like the condenser...also are you in California?

[@HVACRSurvival]

Yes I have done residential for the first 20 years, but I'm in Ohio.

[@HVACR559]

Yes until January 2025. In Cali we will not be aloud to just replace the indoor or outdoor unit, if it isn't one of the new refrigerants.

[@AErefrigeration]

Give us a 3 hour video

[@xenories]

It looks like something low voltage is shorted and when it wants to turn on it shorts main transformer, the proper diagnostic whould be to unplug everything from the board and connect slowly thing back until it trips. Or just chech resistance on everything low voltage. I dont think its the main board.

[@HVACRSurvival]

Well, like I said, I talked to Lennox tech-support and they said it was the board. Because what I unplugged was all the outputs. Also, if it was a short, the amperage would’ve went up on the transformer. I eliminated that even as a possibility by putting the amp meter on there.

[@Gcanno]

Thank you .

[@HVACRSurvival]

You bet! 👍

[@EverythingHVACR]

Saturation, Saturation, Saturation. Nicely done, Rick

[@HVACRSurvival]

Thanks Steve 👍👍

[@MegaDesna]

ALARM 82: Means don't worrey "boutit xD XDD

[@HVACRSurvival]

😅

[@MariosACandRefrigeration]

1 pound of extra refrigerant will make those microchanel trip.

[@subcoolHVAC]

Nice Troubleshooting , thankfully compressors were still good 👍

[@HVACRSurvival]

You got that right!

[@danpresson]

Awesome video

[@HVACRSurvival]

Glad you enjoyed it !

[@HermesVintage]

Any updates on this service call? If the board solved the issue

[@HVACRSurvival]

It just happen Thursday. The store has a HVAC crew that put on a different series controller and it attest has one stage of cooling until the correct board comes in.

[@halverde6373]

Everyday nightmares every service tech is forced to contend with. How much would you be willing to pay anyone to handle that?😰💰🤣

[@paulb4496]

Most Fluke clampmeters don't have an Ohms scale that reads Millions of ohms. If you are testing for a grounded compressor a meter that uses multiple batteries or a 9 volt battery and reads 40 or 60 million ohms will find a grounded winding.

[@HVACRSurvival]

You’re correct, my clamp does 60k ohms max. Generally most shorts are low. If I think I need more resolution I’ll grab my 87V, 117, or my extech megger

[@HVACR559]

​​@@HVACRSurvival I call my 87 V MAX my left hand. I haven't had it fail me yet on diagnosing a shorted compressor. If that meter reads OL in MΩ switch it to nS. nS or nanosiemens is the opposite of ohms. 0.01 nS = 100 GΩ 0.1 nS = 10 GΩ 1 nS = 1 GΩ 10 nS = 100 MΩ As you can see it is a measurement of conductivity the reverse of resistance. There is an overlap with the MΩ selection in the meter. Sometimes it takes a few minutes for it to settle down on a reading. The old non metric way of saying nanosiemens was ℧ MHO, the reverse of Ω OHM. One of these days I will buy a megger.

[@MrJujubean]

Great trouble shooting video. You outta here controller lol

[@brianjones5935]

ya let me just rip into the insulation lol

[@johnwalker890]

Good job Rick, Ghost controller issues is what I call it, I wasn't sure what happened to you?? I thought you were in You Tube jail?? Just kidding, God forbid......

[@HVACRSurvival]

Nope. I mentioned it at the end. Stupid busy and I’m on call

[@johnwalker890]

Well they got the right guy for it....

[@himrfreeze]

In the service mode u can test. Run each compressor and if you jump have to do y g and r and if summer u can leave compressor on in service mode sometime even with faulty board

[@HVACRSurvival]

I need more time with that board. I haven’t had a chance to work with it much.

[@MariosACandRefrigeration]

hello Rick.

[@HVACRSurvival]

What’s up!✌️

[@maliqueldavis3461]

Malique mas ecas unmo a little too late to go to the best

[@CM-ou4zr]

Wow that's a bad diagnosis from the guy before you. Shorted compressor? What are they smoking in ohio rick

[@HVACRSurvival]

They diagnosed that on another unit not that one. I just misread it but the way they wrote the description kind of sucked, but since they’ll probably watch the video, I have to be careful what I say.🤣

[@steveblake8766]

253 thumbs up

[@thefathvacguy6341]

Trane or Lennox....which do I hate more....hmmmm

[@HVACRSurvival]

🤔🤔🤔🤔 the correct answer is…. Both.😅

[@thefathvacguy6341]

@@HVACRSurvival Very true!!! 🤣🤣🤣

[@tysonrojas5477]

Could of megged out compressors and saved time

[@HVACRSurvival]

Yeah, but unless you have a log of what you’ve had in the past, it’s a well-known fact that you can’t just go up there and make a definite guaranteed diagnosis unless it’s really bad short and you can see the super low resistance and the test voltage actually drops. You can have moisture in the system or liquid lane in the compressor and that will give you a low mega meter reading.

[@mitchelljohnston754]

This happened to me, it was one if the 3 fuses