HVACR Fan Switching Relay, How it Works, Voltage, Terminals, Troubleshooting!

[@acservicetechchannel]

The E-Book and Paperback at our Website: www.acservicetech.com/the-book The Paperback at Amazon: www.amazon.com/shop/acservicetech Support the Channel- www.patreon.com/acservicetech Tool List- www.amazon.com/shop/acservicetech For those that are looking for the tools used in the videos: (Linked Below) Electrical Diagnosis Tools: UEI DL389 Multimeter amzn.to/2xAdaJf UEI DL479 Multimeter with temp sensor amzn.to/2jtsUbJ Magnet Jumpers- amzn.to/2PyKPQZ Alligator Jumpers- amzn.to/2PxqJXn Irwin Wire Stripper/Cutter/Crimper amzn.to/2dGTj2V Vacuum Tools: JB 6 CFM Vacuum Pump - amzn.to/2nqbvo8 CPS 4 CFM Vacuum Pump - amzn.to/2DxgPwY Appion Valve Core Removal Tool - amzn.to/2uYr8WL Appion Blue 3/8" to 1/4" Vacuum Hose - amzn.to/2uYlVyc Appion Red 3/8" to 1/4" Vacuum Hose - amzn.to/2uYg6Ro Yellow Jacket 1/4" by 1/4" 3’ hose - amzn.to/2umtcod Appion 1/4" by 1/4" and 3/8” hose - amzn.to/2Zyxzx9 Uniweld 1/4" by 1/4" 2’ hose - amzn.to/2GFov1Y CPS Vacuum Micron Gauge - amzn.to/2v1nM3O Supco Vacuum Micron Gauge - amzn.to/2v1JRiA JB Vacuum Pump Oil - amzn.to/2mGrlXy Checking the Charge: Yellow Jacket Refrigerant Gauge Set amzn.to/2aenwTq Refrigerant hoses with valves amzn.to/2aBumVI Yellow Jacket Gauge set & hoses amzn.to/2vLVkV9 Yellow Jacket 4 Port Manifold w Hoses amzn.to/2BkuGIq Digital Refrigerant Scale amzn.to/2b9oXYl Ratcheting Service Wrench amzn.to/2dGV4Nh FieldpieceSMAN360 Digital Manifold Set amzn.to/2BdoaD4 FieldpieceSMAN460 Digital Manifold Set amzn.to/2nB4Fe6 Compact Ball Valve for Refrigerant Hose amzn.to/2KUisW8 QuickDisconnect 90 for refrigerant hose amzn.to/2MMtVcg RectorSeal Bubble Gas Leak Detector amzn.to/2ckWACn Fieldpiece ST4 Dual Temp Meter amzn.to/2wc1ME3 Fieldpiece Bead K Type Temp Sensor amzn.to/2DBwKfs Fieldpiece Wet Bulb Temp Sensor amzn.to/2RRI7Tw Fieldpiece TC24 Temp Clamp amzn.to/2qHLyjZ Flaring Tools: Yellow Jacket Flaring Tool - amzn.to/2OBxGlM Spin Flaring Bits 1/4", 3/8", 1/2", 5/8", 3/4"- amzn.to/31BCs8Z Yellow Jacket Flaring Tool with Set Depth - amzn.to/2QIKsQH Yellow Jacket Torque Wrench - amzn.to/2NRR68Q Uniweld Swage and Flare Kit- amzn.to/2T55jyn Nylog - amzn.to/2MLJcch Ridgid Tubing Cutter - amzn.to/2DnjjR1 Wolverine Tube Reamer - amzn.to/2QGLyMV Swaging Tools: Manual Copper Tube Swage/Expander- amzn.to/2WRPa1M Spin Swaging Bits 1/4" to 7/8" for the Drill- amzn.to/2YQwwqS Uniweld Hydraulic Swaging Tool- amzn.to/2MlrI8m Uniweld Swage and Flare Kit- amzn.to/2T55jyn Uniweld Hammer Swage kit- amzn.to/2CzWMMU Uniweld 3/4" Hammer Swage- amzn.to/2CzXsSs Uniweld 7/8" Hammer Swage- amzn.to/2Mja5WE Uniweld Multi-Size Hammer Swage- amzn.to/2T3Cx1b Brazing Tools: Air Acetylene Torch setup - amzn.to/2aQalsb 15% Silver Brazing Rods - amzn.to/2gVLyLc Uniweld Cap-N-Hook and #2 Tip Oxy Acetylene Torch Setup - amzn.to/2STp3Fe Ameriflame Oxy Acetylene Torch Setup #1 &#2 Tip - amzn.to/2SRm3JF #2 Tip for Oxy Acetylene Torch - amzn.to/2SPDaeD Cap-N-Hook Tip for Oxy Acetylene Setup - amzn.to/2MbhpUk 40cu B Tank to 10cu MC Tank Acetylene Tank Fitting - amzn.to/2GxZZPi Nitrogen Regulator - amzn.to/2bXdR5f Uniweld NitroVue Flow Regulator - amzn.to/2GnsaAo Uniweld Nitrogen Flow Meter - amzn.to/2brvoBg Bernzomatic Trigger Start Lighter Propane/Mapp Gas - amzn.to/2vit0cv Uniweld Soft Flame Sweating Torch Setup for Acetylene - amzn.to/2DyzRD8 Flint Spark Ignitor - amzn.to/2L3P2u9 Stay Brite #8 Silver Bearing Solder and Flux - amzn.to/2XIDJsY Aluminum Braze Rods - amzn.to/2IGNMu Nitrogen: Uniweld NitroVue Flow Regulator- amzn.to/2GnsaAo Uniweld Nitrogen Flow Meter amzn.to/2brvoBg Nitrogen Regulator amzn.to/2bXdR5f Service Valve & Port Access: RectorSeal Bubble Gas Leak Detector - amzn.to/2ckWACn 25 Valve Cores - amzn.to/2L37UJU 25 ¼” Brass Port Caps with rubber O-rings - amzn.to/2GIOdD2 Brass Valve Core Tool which holds 3 valve cores - amzn.to/2GFEbm2 Valve Core Torque Wrench - amzn.to/2GHiLoD Locking Cap Universal Lock/Unlock Tool - amzn.to/2GGAoVp Locking caps - amzn.to/2GFXZ8A Ratcheting Service Wrench amzn.to/2dGV4Nh Yellow Jacket Sealright 90 Coupler- amzn.to/2LsU1V7 Yellow Jacket 1pk Compact Ball Valve- amzn.to/2uXdF18 Yellow Jacket 3pk Compact Ball Valve- amzn.to/2AiKfQe Thumb Screw Valve Core Depressor with Backseat- amzn.to/2mR0sCL Leak Detection: Accutrak VPE Ultrasonic Leak Detector amzn.to/2nFYKVe Accutrak VPE-GN Ultrasonic Leak Detector amzn.to/2Zy4IZP RectorSeal Bubble Gas Leak Detector - amzn.to/2ckWACn Other tool links can be found in the video description section. Shop through Amazon! Your Purchases through Amazon provide a means for channels such as mine to earn advertising fees from all purchases after clicking through. Prices are the same as normal- www.amazon.com/shop/acservicetech

[@primusheating1]

Just showed my trainee your illustration. He was having a little issues with my explanation of relays. But after viewing your illustration he is much more confident in the relays. You are the man!

[@acservicetechchannel]

I am glad that they help, thanks primus!

[@vernroach3413]

I'm a former instructor, semi retired from running service, and still running service, more than I want, to help people that can't afford the big companies and gougers...I was considered a good instructor, this man, is an Excellent instructor...A great video...I Salute you Teach.

[@aliso-pv7ll]

We need to thank the memory of the American scientist Joseph Henry, who is credited for perfecting the relay as we know it (1835). Let's not forget Michael Faraday, the first to rotate a conductor in a magnetic field(AC), the first to invent the electric motor (extremely simple), and the refrigeration cycle as we know it. As Sir Isaac Newton said; "We stand on the shoulders of giants." Greg, thanks for your excellent videos. They are valuable and informative.

[@acservicetechchannel]

Thanks for mentioning those who have given us these inventions!

[@rookierefrigeration4357]

Great video. Some people still have problems with DPDT relays and this is a great help

[@acservicetechchannel]

Yes for sure, thanks Rookie!

[@iancourter7291]

Thanks for this wonderful video Craig. I'm an HVAC installer but I'm trying to learn some of those beautiful skills and knowledge you service techs have ;) This helps a lot!

[@acservicetechchannel]

Glad you enjoyed it

[@marioquintero7827]

You can do it man I'm a service tech I still come in to re learn

[@scrambler350]

Awesome. Wish I was able to watch this video when I first started 4yrs ago - perfect job of explaining the function visually. I had to make a similar 'test bench' set-up with a transformer and a bunch of different sequencers and relays then spend some time powering them up and ohming them out to get it straight in my head so I was ready to troubleshoot effectively.

[@acservicetechchannel]

Yeah thats what we did with the students at school. Wire test and fault them! Thanks!

[@josephmorales3728]

Me too this men teach very good

[@sphinxceo]

This is a great video. I've been Googling a lot since my espresso machine stopped heating up. It has a DPST power relay. Your video is the only one that explains what the ratings are on the side of the relay. And your testing is simple to follow. Thank you very much. 🤠

[@mperry94]

Thank you for this one! I'm still trying to wrap my head around relays and sequencers and this was incredibly helpful.

[@Okie-Tom]

Very good demonstration! Thank you. I have been working on my own HVAC relays at the house!

[@carmechanic5497]

You are simply an Amazing Teacher!!!!

[@YTubeViewer12]

This video helped me to finally figure out how a relay in my swimming pool works. Thank you.

[@acservicetechchannel]

Glad it helped

[@jamesortolano3983]

Great watchin AC Service Tech channel!! Started in 04,was in residential electric,nd hydronic heating even before that . Only had books nd hands on experience back then . When I learned this no one could explain the way CRAIG does. It's a good feeling when I know people are benefiting from this information, keep it up looking for to the next one ✌

[@McmM-cv9sb]

You always have good information you are a very good instructor I enjoy all of your programs thanks for sharing it...

[@kylelikeskjvbible]

Its funny how for me as an electrical student, i learn much better quality stuff (like this video and HOW something actually works) from HVAC guys than I do electrical guys LOL.

[@marioquintero7827]

LOL

[@NativeBowhunter1965]

I’m new to service work but long time duct installer. Now I understand how they work, Great job of explaining! Now I just have to figure out how to wire them in without blowing something. Could you make a video of that please?

[@robertl.7657]

That's what I call ,Real explanation ,can you do troubleshooting videos, like most AC, units have, (capacitor, low refrigerant, relays,fans,low air flow etc,

[@acservicetechchannel]

Robert, look up our switches and relays video playlist for many others. We also wrote articles on our website www.acservicetech.com for frozen evap coil, liquid line restriction and others. We put a whole book out on working with refrigerant, ac and heat pump units. In the book we go over the basics all the way through to troubleshooting by measuring the refrigerant charge and troubleshooting airflow problems. The whole outline is posted at www.acservicetech.com/the-book thanks!

[@josephmorales3728]

You the best you teach better , my Teacher did not teach like this . Thanks .

[@acservicetechchannel]

I am glad that you are enjoying the videos Joseph!

[@izzymoney85]

Hey thanks acservicetech i learned a little bit more about relays and how they really work really well done keep up the good work!!😎🙏

[@acservicetechchannel]

Thanks a lot Esmar!

[@purrungas2012]

Excellent training, brief and clear

[@jacksarisun6640]

Thank you so much for this valuable information and educational video.

[@timcollin9107]

Your videos are always top notch, Thanks for sharing . I was taught that testing resistance while power is on could be damaging to your meter and you have done this throughout the videos. Have i got this wrong

[@acservicetechchannel]

the 24v circuit with the coil is seperate from the open or closed contacts, thanks!

[@vby9588]

awesome video. that is exactly what I need to know

[@terie1984]

Same. This guy deserves to be paid for all this free info that is life saving on jobs.

[@sayyymayne4214]

Should not be getting continuity between 5&2 or 6&4 at any point, correct?

[@jethzeeltorres9727]

Awesome illustration

[@marioquintero7827]

That line in the midle of the first switch from 2 & 4 and 5 & 6 is trippy 😳

[@FrancinahPatletswane]

Riley for fen restaurants for fire lendar2

[@FrancinahPatletswane]

Give mi the vidio for frilandar2 rily

[@branislavignjatov7088]

Craig, God bless you and thank you!

[@dylansasson6756]

Excellent explanation. I finally get it!

[@TheUnknownCatWarrior]

Clear and informative video

[@acservicetechchannel]

Glad you liked it

[@kerrispringer6934]

Very thorough explanation. Thank you!

[@acservicetechchannel]

Glad it was helpful!

[@deanburke3041]

Broken relays inside water source heat pumps can be very confusing. But, I found testing each one in sequence understanding what each one does clearly wasn't so bad. Usually they are so common & cheap I just replaced all at once so everything works. A no brainier.

[@rachidsabri5787]

Thanks for this wonderful video. Why the switching relay make clicking noise continuously

[@kennyw7453]

Excellent video

[@acservicetechchannel]

Thanks Kenny!

[@childog777]

Great videos!!! What I am looking for is help with an old furnace that does not have a fan (G) or a W wire. Y,O,R = Cold, Y,R = hot. There is no fan (G) wire. There is also a B-marked wire. The issue I am having is that after the cold cycle and temperature is reached, something sticks which keeps the heat on. The second problem I seem to have is that if I connect O only the fans run continuously. The new thermostat powers O even when it is not cooling. Also note there is no control board, just wire to wire devices such as a SPST mounted on a metal surface.

[@HPTube]

Thank you for the great visualization! My 90-380 is humming rather loudly. Is that normal?

[@kevinlarson3996]

Great job as always

[@acservicetechchannel]

Thanks a lot Kevin!

[@kev2tube]

This is very well done. I have a question. My fan stopped altogether. I ran tests on the fan. all is well. When I tested the relay on the bench it worked great. When I powered it up via the fan "on", both 2-4 & 5-6 turn on simultaneously. I put in a new relay, but the same thing happens. What could be the cause?

[@r.t.7925]

Excellent explanation as always :)

[@acservicetechchannel]

Thanks RT!

[@mohammedalobaidi9981]

Great description.

[@geraldschilli8870]

What about discussing the difference between power duty contacts and pilot duty contacts & the material composition of each type of contacts.

[@HsingSun]

Thank you for your video. My thermostat system kept running, non-stop for cooling. Would it be the fan switching relay problem?

[@MrGeoffois]

My neighbor's hvac heater seems to light the furnace fine but when the blower comes on you can hear the click then it comes on for a half a second then clicks off then on and does that 15 times then stays on. It's been doing that for years she said. I'm wondering if the relay is going bad or the heat sensor fan control switch could be going bad so not staying closed till the heater keeps getting hotter. When the heat signal isn't being sent from the thermostat the system cycles off but the fan does come back on in the end for a second then back off. It sounds like the fan is ramping up when it starts. The furnace stays lit. What things could this be. I scheduled an hvac guy to come but just so I have an idea.

[@Cchall22]

Great video.

[@Pretzel114]

Great video as always!!!! Wanted to ask, you wouldn't have to use all the terminals if you did not need them right? Thanks again.

[@acservicetechchannel]

Correct, thanks Nick!

[@Pretzel114]

@@acservicetechchannel Thank you for the quick reply. Take care.

[@jimbola77]

excellent video thank's for sharing!!!!!.

[@acservicetechchannel]

Thanks Jimbola77!

[@josedelsonpadernal9019]

your video help me and our trainee in DOM RAC NC II for further elaboration how relay will works..thanks..

[@acservicetechchannel]

Awesome, thanks Jose!

[@alexv3866]

Great, thank you!

[@acservicetechchannel]

You are welcome!

[@electricboogie709]

Superb!

[@acservicetechchannel]

Thanks!

[@Alex-jo2oi]

Fan motor won’t turn on. Is it because of the relay? I checked for resistance on the motor wires and they check out fine. High voltage is getting to the terminals as well.

[@fredericka.furmansr.2489]

I learned a lot 👌

[@andrewthacker114]

Good clip thanks

[@jeffhoya542]

Should the coil get very hot when in use?

[@mikebordeaux8218]

The relay on my Goodman is a white Rodgers 134 20102 106 with 14 fla , 84 lra and 7 fla , 42 lra the parts store don’t have this so they sold me a supco 90290 with 8 fla and 25 lra. Is this a suitable replacement? Thank you.

[@osmankjr7150]

so when u plug in the wire into the relay and connect the jumper. reading should be say like 00 or 01 or 2 is good. but when your checking the coil now that’s different. u just use jumper to check ? so that reading should show higher number like 89.? if it low, it’s bad.

[@HanPro]

I have a computer board fried under the relay. Could I bypass the relay temporarily until the new board arrives?

[@rjohnson4720]

What does it mean if the condenser fan relay only reads 24volts at the point the black wire from the fan motor connects? Shouldn’t it be 240?

[@xtremecomfort7799]

Thanks!!!!!!!

[@acservicetechchannel]

Glad to help!

[@xtremecomfort7799]

Very Helpful!Thanks Again!

[@user-tr9to2bh6x]

Thank you 🙏

[@acservicetechchannel]

Glad to help Mohammed Ali!

[@AndySwaggly]

Why do we read 0hms on the coil during testing but in common problems it’s 86 and good

[@lionelallen4142]

Where can I find the socket for these relays?

[@moonlightacmaintenance3232]

Is a relay similar to a single pole contactor with a shunt?

[@marcelangers9953]

When are you doing relays on boards?

[@acservicetechchannel]

Marcel, I was just mentioning the same troubleshooting problems that relays have, boards have too. If control voltage is going in and power is not making out of the relay then the relay on the board is bad, thanks!

[@scsclassics]

​@@acservicetechchannel3 yrs still waiting.

[@mts7274]

What does it mean when the relay buzzes really loud, but the fan doesn't come on?

[@usahole1649]

So my indoor fan constantly running could be that 4 and 5 are stuck open?

[@matrix2030x]

how much should cost to replace relay switch to blower.. does 700 sound reasonable

[@drewn4344]

If the contacts are burnt or pitted, is it possible to take a fine course file & clean them?

[@acservicetechchannel]

They shouldn't be cleaned because they have to be absolutely smooth and these are relays that most techs stock in the service truck, thanks!

[@drewn4344]

@@acservicetechchannel I'll probably buy one myself. I'm not paying all that labor and mark up. I used to be a tech myself long ago.

[@acservicetechchannel]

Got ya thanks!

[@tuoqiu8328]

My HVAC air handler wont turn off. one guy said i need to replace the fan motor. are there any possibilities that bad motor cause fan wont turn off?

[@officerkrupke4966]

Yes, if it is an x-13 which has a built in control board. There is a low voltage signal wire going to motor if it is x 13, disconnect low voltage speed control wire. If it continues to run than the motor is bad. If it is a motor that has a capacitor connected to blower housing, than no, it is not a bad motor, just one that has a bad control circuit somewhere. Whenever touching wires always disconnect power first.

[@KyleWithStyle7]

what does the number mean before the lra?

[@jasonseifried7192]

Ty

[@Wwasgud]

My brain hurts, i need this in baby terms. The close and open thing

[@FrancinahPatletswane]

Water cooler for land driver frelender2

[@gilbertespinoza7955]

I know you could make it with a contactor can you show us pls

[@stevethompson6514]

blower fan doesn't work on auto does work on manual any help

[@officerkrupke4966]

Replace thermostat.

[@BYENZER]

CRAIG! That relay, TOP LEFT, looks like a DC relay!!!! kzbin.info/www/bejne/nKmZaJ-oZdqDaas

[@johngatsby1473]

So my ac and heat are running at the same time and that's even after totally removing the thermostat and isolating all the wires..... Would this lil booger cause all that?

[@Lags-zl3wy]

Can a damaged condenser fan relay prevent 24v to go to the condenser contactor?

[@Mabalzitch2024]

Thank you for sharing your knowledge. Great video with exceptional explanation!

[@acservicetechchannel]

Thank you for your support!