e103 error

[Jacquanette3]

My thermostat, which I installed in 2017 and haven’t had any issues with, is suddenly giving me the e103 error for wire Y1. I have not touched it since install. Since getting the error, I’ve followed the troubleshooting guide,  removed all the wires and re wired them. Still no change. Do I really need to get an HVAC person out here for this nonsense? 

[OverIT]

Look in the upper compartment of the air handler inside. Look for a purple fuse that says three as in three amps and see if it's blown. If it is you can get a new fuse at any Auto repair shop replace it and you may be back in business.

[Jacquanette3]

It appears, but I have no way of testing it. 

 

[MJWimsatt]

Did this work for you? I too, installed mine in 2017 and have the exact problem! Never had trouble until now....getting really frustrated!!!

[Sheri1]

Yes, it was that component and the connector had gone bad.  He also replaced the condenser saying it was going, The Nest thermostat was fine once those components were replaced.

[Jude2022-8-23]

Me Too!  Installed in new house in 2017. Same problem....Suddenly it's got a mind of it's own! 

[Sheri1]

Yes, it was that component and the connector had gone bad.  He also replaced the condenser saying it was going, The Nest thermostat was fine once those components were replaced.

[Sultanianviken3]

Where is the fuse?

[Ryan_G]

Hey folks,

I just wanted to follow up and see if anyone is still in need of help? Please let me know, as I would be happy to answer any questions you may have.

Best regards,

Ryan

[Jacquanette3]

Still isn’t working. Took the side panel off the AC and the capacitor looks like it’s in good shape. The amp doesn’t look bad either. But I have no means of testing it. I don’t feel confident messing around with my fuse box and probably wouldn’t know what I’m looking at anyways. I can send pics of what my Nest is saying if needed. 

[Sheri1]

Yes, it was that component and the connector had gone bad.  He also replaced the condenser saying it was going, The Nest thermostat was fine once those components were replaced.

[zschiffman]

Same issue today with first use of ac for the season. No issue since install in 2019

[Sheri1]

Hi Ryan, I have gotten the e103 error.  I have not had any problem with this Nest Thermostat installed two years ago.  I recently changed the setting from heat to cool.  (It wasn't hot enough inside the house to turn on the AC yet, but warm enough I knew I would not need the heater and I wanted it prepared to come on when necessary.  I also changed the setting to come on at 80°.) I took the face plate off and the Y1 has a yellow wire going to it.  I see the button on the outside edge of the Y1 button is depressed.  (Also the G, W1 and Rh buttons are depressed.)  The rest of the buttons are up.  The AC had not tried to come on before this message, but did try to come on one day after the message making me think it was working. (But I think it was just the fan coming on.)  This weekend it will be 103°.  I would appreciate any help.  Thank You!

Sheri

[amit007]

I have the exact same problem. I tried to start the hot/cold mode of the thermostat for the first time this season. The ac started, at least that's what the app showed on my phone. After a while, when the home didn't get cold enough, I checked and nothing seems to work with Nest. I can't even find a proper youtube video explaining it. 

[Sheri1]

AC guy replace the connector and condenser and the component shown above and then the Nest was fine.

[Sheri1]

It is not the Nest.  It was the connector, condenser and the component shown above.

[MJWimsatt]

I am having the same issue as everyone here!! Ridiculous that the same issue keeps coming up! As Jaquanette stated, I had this installed in 201 7 and have never touched it, nor had any problems, until now and today was 89 degrees.... it seems that a Nest replacement is also futile. What can be done without wasting a lot of money???

[Sheri1]

See my reply above

[Sultanianviken3]

E103 code?

[TonyPalleschi]

Hi Ryan, mine is currently giving me this code and I don’t know where to find the fuse they are asking about. I have a roof mounted A/C unit, is it going to be up there? 

[Indyguy]

Had the same e103 error last yesterday morning around 5am. Woke up at six (hot) and checked the fuse (good) unhooked Y at heatpump and error didn't come up. (Maybe I didn't wait long enough). I chalked it up as a bad defrost board. I go back inside a lay on the couch. 15 mins later a feel cold air...ac is now working. I thought great...must've been a loose wire. Ac Workday great all day and night. The following morning I wake up...same issue!! I'm guess it's the tstat??? Condenser boards don't give out and and come back. Same error code e103 

[Kjghome]

So is the issue with the thermostat or the ac unit itself? Where are these fuses, components and connectors located?

[Weppinger]

Contactor is located in outside ac unit. This should be checked, but is not only possible cause. Fuse is likely mounted on control board in inside air handler unit.

[golephish]

Having the same issue. I thought it mat be a bad base, so I ordered a new nest. Setup, did the test, and now nothing. I am starting to think it is the C wire issue as I don't have one. My current theory is that the capacitor blew on the unit over the past year as I did't have said C wire.  Searching for HVAC and seeing what the next money sink is. very disappointed as like the rest of the posts here, it has been working with no issue until Sunday night.

[Srch4me]

I called nest. They walked me thru remiving the C wire connector in the thermostat.  Told to reconnect when I turn in the heat. Works but don't care for the solution. Looks like nest has a glitch. Hadn't touched the thermostat since install. Just turned in the A/C. 

[juneferg]

I am having this issue right now too, just move into a house that has a relatively new Nest. You are saying that this worked for now as a temporary solution? To disconnect the C wire in the thermostat?

I am seeing a lot on Reddit about replacing the contactor on the outside unit. That might be my next move after trying this C wire thing if recommended. It's about be to 97 degrees this weekend and I can't get anyone to come out until next week.

[Srch4me]

Yes. Sorry for the typos. Disconnected C wire. Was told by nest to reconnect when I turn the heat on. All seems to be working fine. My system is five years old. No chewed wires. Fuse is fine. No icing outside or constant running of the compressor. Nest is 2-3 years old 3rd gen. Leaving it alone for now. 

[amit007]

I just turned on the heating/cooling option and the system became unresponsive with error code 103. I am seeing all sorts of answers. There is a 13 minute youtube video, but the comments there leave some doubt. Did anyone above finally resolve it?

[juneferg]

I did all the troubleshooting I could with Nest, and ultimately they said it was my HVAC. Had a guy out, and it was indeed the same solve most other folks had posted about over on Reddit, needing a new contactor in the outside unit/condenser. Apparently it's fairly easy to replace (people bought the part that matched their's on Amazon), but I wanted to be sure and also am not quite that handy. 

Ultimately he said something was up with the outside wire which caused the fuse to blow before the thermostat/inside unit could even talk to the outside unit (hence the system starting and stopping repeatedly every 30 seconds without getting it to stick on).

The thread is here in case it's of interest: https://www.reddit.com/r/Nest/comments/crw124/nest_error_e103_y1_wire_tried_many_things/

But I would suggest having someone out to take a look and make sure that's the issue / make sure they solve if it's a broader nest and voltage issue.

[Sheri1]

It was the connector in the AC unit and two other components (one dead and the other going).  After those were replaced the Nest was fine.

[verytalleric]

+1 here. As with others, has been running fine for 1 year until today. What I'm seeing not listed in thread above is that if I unplug the head unit and reconnect, AC will start up fine but then 5-10 min later Nest throws the same error again. Given it works every time after I unplug + reconnect (for awhile) I'm very suspicious on the Nest unit itself.... Don't really want to pay for a service call....

I've already rebooted the Nest and reset breaker to AC + furnace several times

[verytalleric]

Following up. As with everyone else, a bad connector. Might be nice for the Nest dev team to add some logic along lines of "if unit has been working for some time and starts having this error, don't poiint to bad wiring and instead point to a bad connector"

[amit007]

So the HVAC and AC guy came today. It was a connector problem, as everyone has mentioned above. The only problem is that the ac didn't work when the temperature was 91 over the past four days. It is working today when it's 70. The part was under warranty so the guy didn't charge me for that. 

[danbodell]

Not sure if this is still a live thread or not. I just signed up for this community, so be patient if I ask stupid questions.

3rd generation thermostat, worked great for 3 years.  It's been my gateway drug to a smartish home.

I now have the same e103 y1 wire issue being reported. Outdoor condenser unit stutters without starting. I had a guy that replaced the two electronic elements at the condenser, the contactor (switch looking item above) and the capacitor (the one that looks like a small can of Red Bull). Same issue continues.

What he noticed, but haven't seen mentioned here, is that the thermostat itself is warm to the touch. And we're only getting 10 volts out at the condenser from the thermostat. 

So we just connected the cool/fan/ power wires with a wire nut and the system runs fine. 

Could it be my Nest is bad? It is Amazon Prime day after all.

[Weppinger]

Could be partial short in wiring, or could be Thermostat. You should see 24v. Check voltage at various points along y1 wire, starting at Thermostat itself, disconnecting wire along those same points at available connections.

[nirsalon]

Same happened for me. After reading online I understood that many had a bad AC contactor. This piece breaks from time to time and should be replaced. I watched a YouTube video, order a new contactor from Amazon for 15$, replaced it myself, and everything now works.

[Petemillsy1]

As others have stated replacing the contacter on the outdoor condenser unit fixed this issue for me. Low to medium difficulty to DIY.

[Weppinger]

Error in my case was caused by a faulty contactor in outside ac unit. This acts like a power relay to switch on the outside unit.  Nest is sensitive, even to partial short in this component, which may not blow fuse in inside air handling unit. Note that Thermostat can be damaged if it is used repeatedly with this component fault present. There could be other causes as well, such as bad wire (chafed, chewed, etc.).

[nbouteller]

I had same issue, ended up being the low pressure switch wire was touching the suction line on the compressor and wore though the insulation and shorted out, repaired wire, all good. this was on a Carrier 4 ton package unit