HVAC: Lennox Blower Relay & Defrost Board Replacement

[@josemelendez9919]

I have had a lot of issues with that lennox board, almost in every heat pump I have worked on. I really believe is a manufacturing defect.

[@andygalindo8978]

First time I saw this video it did not mean much to me. Second time I understood a lot of how it works and I realize how important this video is. Thanks for making it.

[@DECandleLady]

Thank you for this video, just helped my HVAC brother and I diagnose a bad coil sensor based on blinking light speeds. Couldn’t have done it without you, you’re the best! 😂

[@Love4raine]

Well as I’m sitting up here on the roof of the hospital where I work in Maintenance I’m scrolling thru looking for the cause of my blower on this big LENNOX RTU to be constantly running . Well this was the problem. I’m NOT an HVAC specialist but the more I watch these videos the more simple these things become.

[@acrservicesmathewr7565]

Omg John I had the same exact problem with the same exact model. No 24volts to contactor from y1 and comm. Jumped the contactor from y and comm from thermostat and it pulled right in. Checked board and no burns so deff that little relay. You have just confirmed my diagnosis. Good work bro

[@davidsullivan7867]

Just replaced my defrost control board, on an older HP29036-1p, with the same board you're showing, . The original board for my unit had two red led lights, which had the outer high press & low press terminals jumped out with a single wire ..per the schematic.. The only reason the board got replaced was because low voltage terminal block had developed an intermittent connection issue with the control board, which prevented the compressor from coming on. Anyway, long story short my unit apparently did not come with press switches. I kept the factory jumpers in place on the new control board & the unit works fine again. Still a very useful video because with power applied, the unit went into the same 5 minute anti short delay that you depicted. I had no idea what that was until watching your video because the older board didn't do that ....Thx again from an avid do it yourself home owner!

[@justinfrias9030]

So cool you work on Lennox now! Can't wait for more vids!

[@randykocian4738]

Thanks, John. Great video. It's rare to have the knowledge of running an hvac business and working for an hvac business. A different perspective.

[@LexVance]

Good to see you jammin again John! Nothing like some 100 watt vipers while a skid bro works. Keep'em coming!

[@adrianwilson1191]

Came to check a board replacement and left with a new awesome band. How I’ve not heard of 100 Watt Vipers before?

[@kraigstrom]

Magic! I applied some pressure to several points on my old lennox control board and the system popped on. I guess I need a new circuit board.

[@johnisraelhvac2019]

Thanks everybody!!! I Appercaite the great comments!!

[@timwilson1840]

Nice.Yea my defrost board came with those jumpers.I think my blower squirrel cage needs to be changed.It had alot of insulation stuck to the blades.Now my evaporater is freezing up.Got the blower running and drain line still running out steady.

[@Powlashvac]

Great to see you still able to do videos. We would be saddened if you were not able to do so. Keep up the great work and videos.

[@JurassicJolts]

This is my exact issue. I am glad you made this video to confirm my diagnosis. Thanks

[@zacksintheshop]

Nice video John, #cowboysofhvac . I think the extra jumpers might be for units that do not have those pressure switches.

[@johnisraelhvac2019]

I believe your right my friend

[@user-zi6os4jv6w]

The jumper are for diagnosing. Instead of cutting and splicing, u can jump them out simulating good low and hi psi switches

[@kennysimmons3955]

Great video. Keep up the great work. Let us know how your doing and how you like the new job!

[@amattar02]

That defrost board is used in several Lennox HP models, not all of them have pressure switches. Mostly seen in Elite series upto 2014, now more common in all of their models.

[@The300mcm]

my heatpump quit last night wouldn't do anything here its 23 deg wind blowing ugh! it was the capacitor.bad that control blower motor luckily I had one guess the high pressure switch cut it out. it's a good idea to buy the capacitors u need keep on hand they not expensive cause they will fail and at worst times mine went out at 3 am . thanks man enjoy your videos

[@tommyt5815]

Steve Lav showed a nice trick with bic pens to pop them boards it’s genius lol great video

[@Pyridox]

Nice work. Thanks for keeping the videos coming!

[@danoberkirsch5282]

You can jump out the test pins and terminate the 5 min delay. And Yes some of Lennox lower end equipment uses that same board but does not have the pressure switches Thanks for the videos

[@kenlee8176]

I also have a Lennox, temp can’t go below a 82-83. Not cooling properly. In the attic there is some water on the pan. I had cleaned the coils on the outside unit and also cleaned out the AC condensate drain and still running 82-83.?? Any ideas?

[@lokichoki_]

I just had this happen at my house with a HP22 it looks like white flies infiltrated somehow , had diagnosed up to the the thermostat calling but it wasn't getting to the contacter so checked everything I'm not a circuit guy so when you said it it made sense

[@frankyb9682]

I like your videos John. Very good info. I have a Lennox 13 seer 2ton heat pump. When set to cooling mode it runs fine but in heating mode 24vac is not getting to the Defrost board via Y. Can you give me a pointer on this?

[@aaronshoyt]

On my board i have no lights working, the code means no power, but i have power 24v. Do you think that part of tge board is also bad? I know my board is bad cause i have no 24 volts coming out of board.

[@meerscan9101]

good video, short and sweet, keep them all like that! straight to the point, no coulda-woulda-shoulda, just do it and get-er-done

[@michaelralph441]

So, how do you get rid of the 24V draw from the thermostat? I know you discharge the capacitor but how do you eliminate the 24v so you don't get shocked? Thanks

[@veteranjeeper1120]

I'm messing with a customer lennox heat pump today, we have power to the R and C but can't get it to the Y, O or W is that typical for a bad lennox defrost?

[@NestorHVAC]

Nice job like always!!! Keep them coming.

[@hvacrjunky6119]

Thanks for the tip on the jumpers!😎 Good video.

[@VeryPersian]

It seems like you change a lot of defrost boards. Any speculation why?

[@allhoursmaintenance3022]

Thanks for the video. Is the labor warrantied as well?

[@johnisraelhvac2019]

+All Hours Maintenance No the labor is not warranty

[@stephenhannahjack]

Hi thanks for your videos I do appreciate them. Quick question I may have some wires reversed. can you tell me what ACB stands for on a Lennox circuit board? Model diplomat 80MGF SERIES. I have 3 terminals heat, Low, cool. The wires that come from the main blower (black and red) are connected there. I'm wondering if I mixed them up. My Blower constantly runs and all limit switches are fine. Thanks for any help/clarification.

[@barryabel2687]

You have a part number for that board

[@MrJRHacker]

how are you doing with hours? Different from being by yourself?

[@crazydan2327]

Not all units have a high end low pressure switches that's why they install jumper

[@2A_ALL_DAY]

Hey bud I enjoy your videos! I do refrigeration up in New York. Different but the same lol. Take care

[@SteveSam66]

John, nice job..

[@joshuapoche5137]

Hey brother how you been liking tge weather lately. It sure has been beautiful here in Louisiana.

[@harrydickson4575]

Nice work John

[@noevirgen15]

Very good video helped me a lot

[@SuperBear1001]

Good stuff! Really appreciate your video.

[@MrFrozen73]

So how do you like your new job, John?? Are the hrs better than working yourself? More time with the family? Making same or less $$$ ? Nice vid keep it up !

[@MsFishingdog]

Great video. good job. thanks.

[@eagletek1]

great video. thanks for sharing. Who sings the song walk so heavy?

[@zeke112964]

+Eagle Mechanical Refrigeration/Hvac Durham N.C 100 Watt Vipers is the band

[@jhhvacplumbing1944]

Nice work john

[@robertorodriguez4803]

I’m having problems with a Lennox unit fuse keeps blowing thermostat wire is New but as soon as the outside condenser tries to turn on fuse blows

[@johnisraelhvac2019]

Probably a shorted contactor coil

[@fireinthesky4982]

4:21 Band sort of sounds like Clutch.

[@theairconditioningguy]

Nice job! Keep em coming! 👍☺

[@TheGhettoLobster]

Nice drop light btw I have the same one!

[@wjwhvac-r-inc5542]

Hey what's up how they treating you.....?

[@corywade4702]

Mine is doing the same that cause the blower not to spin

[@tonyelijahclaye1081]

Thanks

[@texasmade2684]

Now your working for a big company is there pressure to sale new equipment? Does it bother you that you have to sale Lennox and not what you think is a better unit? Just asking cause im in the same position. I took over my father-in-laws old business but not getting the output I want and thinking of moving to a bigger company.

[@lchavez6973]

Texas Made Lennox is the shit

[@lonniecleveland4560]

thanks for the tip

[@joekatynski8171]

I gotta say I'm not a fan of Lennox oil furnaces but there gas units aren't that bad

[@glasser2819]

WTF Lennox: 5 Amp relay on a 10A inductive motor load... (should be rated @15A or up) 1 Amp relay welded ON by spikes from heavy duty contactor coil (should be rated @5A or up) Replacements parts not gonna last long.... 🙂 👍🏻

[@TheGhettoLobster]

I hate lennox units

[@leorael4497]

I have the lennox also , my ac still runs ,not turning off once hits target temp , would this be the relay ?