This video isn't getting enough attention. For me, it ended up being the fuse. Thanks for the clear and CONCISE troubleshooting. We need more videos like this!
So helpful! I was leaving the panel off to show my kids and wasn't sure why I couldn't get it to work after I replaced the fuse. This video very helpfully noted that the panel being off deactivates the power!!! That one little critical part might have led me to calling in an electrician. Fortunately, this video mentioned it when others left that part off . . .
Thanks for taking the time to record this video. Added mulch outside without realizing that I clogged the outside drain. Cleared the drain and back to working perfectly.
OUTSTANDING video, comprehensive, to the point and easy to follow. This video should serve as a model for all UA-cam content creators. Immediate start to the sought content, timestamps for the various options, and no obtrusive sales pitches. After going through all of the diagnoses, it turned out to be a flooded drain pan outside. Thank you sir, well done. A like, a comment, ringing the bell, a sub, and I might even mow your lawn if you keep this up.
Thanks for the video! Any suggestion for a recurring e74 error? I noted today ac wasn’t on and went through my normal checks. No breaker, dry pan and fuse appeared to be in tacked. I go to UA-cam to search for answers and hear my ac kick on and resolved the problem itself?! Moments later it goes out again but once again resolved on itself?! Thanks for any advice 🙏
If it keeps coming on and off, it’s likely due to the consensation line not flowing well. You can check out this video on how to check the condensation line: ua-cam.com/video/AiBFL-l0uxY/v-deo.htmlsi=l5dboXvqG975IsW0 Also make sure the air filters are clean.
@@randomhomegadgets Last night I went back through your diagnosis’s and it was in fact the the float switch! The drain pain underneath the unit was bone dry so I didn’t think it could be that but when opening the side panel I noticed some slight puddling inside the unit underneath the coils. Checked the float switch and as soon as I pulled it out the AC kicked on! You are a rockstar my friend 💪
Great video, thanks for the tips! I have a pretty weird issue - I'm getting this error while the heating is on (and it is only visible through the Nest app). So, once I kick off the heating, it can blow hot air for 5-6 minutes and then stop for 1-2 minutes and after go on again. So, it goes on and off and at the moment it stops I do see E74 error on the app (but the unit display either shows a "Delayed" message or just continues showing that the heating mode is on). Any ideas about what is happening? I do have 2 more Nest Thermostats in my house, and others works without any issues (same wiring at the base and at the HVAC for all units)
This error means that the C wire is not giving enough power to charge the best display. You can use a voltage tester to test the voltage between C wire and the heating wire, should be 24V. If it’s less than that or fluctuate, then there’s a problem with the furnace main board. If the voltage is stable, then there’s a problem with the thermostat itself (may try to swap out the unit display to the ones that you know is working and see if the problem goes away).
@@randomhomegadgets thanks a lot for your reply! I've just measured all my 3 thermostats on each level and they all give me the same readings between C and Rh wires - about 28V (it's fluctuating, but slightly around 27.89-28.01V) I've also tried Google Nest 2nd gen and two units of third-gen and still getting this error...
Hmm, in that case that’s likely some problem with the heater main board. Sorry this is beyond my knowledge level. Probably should check with a HVAC technician.
Diagnosis 5, the power switch to the furnace (which was my case) can break from the connection terminal and either loosen up the wire or totally disconnect from the terminal. Over the years extreme temperature conditions in the attic can cause the plastic crack and separate from the terminal. Replacing the blown fuse is not a permanent solution. Usually when the fuse blows, that means there’s another problem that keeps reoccurring.
Thanks for this video! Looks like my issue was more or less related to diagnosis 1. Either my wife or I may have inadvertently bumped into the power switch on our furnace when bringing out the holiday decorations from the basement 😂 🤦♂️
ez trap for furnace cooling system was clogged with some debris and water setting off the "trap" signal resulting in the E74 error code for my nest. Thanks for the video
Hello - I'm getting intermittent E74 error on cooling. I checked the drain line, Fuse, wiring all seems ok. I need to restart the furnace to get the nest thermostat to work. I have outdoor AC unit and Lennox G61MPV furnace. Any help suggestions pls.
Check to see if you have an in-line float switch. If you have one, open it and see if there’s water backing up in there. It’s likely that the drain pipe is partially clotted and takes a longer time to clear out the water. So when water backs up to the float switch, it shuts off the AC
Yes, they should be all inside the packaged unit outside the house. How to get to it depends on the specific units. But usually there should be panel that you can open and look inside.
Thanks for the info. But none of those were my issue. Had the same error code. I pulled the face off and pushed the rh wire around a little and put the cover (interface or what ever it's called) back on and it works now. I think it just needed a hard restart 🤷♂️ I guess. Plus main power went off to the unit. Big storm rolled through.
Thanks for your comment. Probably the error code came up when the main power went out. The Google nest didn’t recognize that the power was back on until you took it out and put it back on again.
lately every time I turn on the Heater works but after riches for example 72 turns off but again turns back on right away and gives me code E74 I didn't have this problem before
Did all you said but am still having the E74 error code new board new transformer still having same issue it work for a day are two are even couple hrs then bam it's out and E74 help
If it keeps coming on and off, it’s likely due to the consensation line not flowing well. You can check out this video on how to check the condensation line: ua-cam.com/video/AiBFL-l0uxY/v-deo.htmlsi=l5dboXvqG975IsW0
I checked everything and I keep getting the error code. I comes and goes for hours at a time. Works for a while then the error comes back when ever it wants.
Check if you have a in line flow switch. It could be that the drain pipe is partially clotted so the flow switch turn off the HVAC frequently when the water is backed up, then turn it back on when the water is able to get out.
Yah, since there’s no power going to the thermostat, it will slowly drain out its battery. There’s a micro USB port at the bottom of it, you may use it to charge the battery.
It could be that your HVAC restarting itself. Sometimes if the HVAC is too hot and not able to vent the air fast enough, it will temporarily shutdown and reset.
Commenting on all these videos with the fix that I found hoping it will help someone. I simply hit the emergency power light switch to my gas furnace. Once I flipped the power back on, everything was fine. I must have switched it off by mistake moving stuff up and down the basement steps where the switch is.
I have 8 zones…7 of the thermostats are working…one doesn’t work…e74 code…no power to Rh wire…what do you think it is…I don’t see a drain pan outside by the HVAC system…
This video isn't getting enough attention. For me, it ended up being the fuse. Thanks for the clear and CONCISE troubleshooting. We need more videos like this!
Thanks for your comment. Same here, I got a blown fuse too :)
@@randomhomegadgets Hello, I live in an apartment.. where would the HVAC fuse be? Is that typically in the garage or on the roof?
For an apartment building, it's usually on the roof. But most likely you won't be allow to access it unless you are the building maintenance person.
Same here, fuse was the issue. I know this is a 1 year old comment but adding to the thread so this video gets more visibility.
So helpful! I was leaving the panel off to show my kids and wasn't sure why I couldn't get it to work after I replaced the fuse. This video very helpfully noted that the panel being off deactivates the power!!! That one little critical part might have led me to calling in an electrician. Fortunately, this video mentioned it when others left that part off . . .
Glad that you find it helpful. Sometimes we think way ahead of ourselves and forgets the basic steps :)
Is this the unit inside or the one outside?
Really appreciate your video, resolved my issue with no need to pay an expensive technician
Glad it helped :)
Thanks for taking the time to record this video. Added mulch outside without realizing that I clogged the outside drain. Cleared the drain and back to working perfectly.
Glad it’s helpful for you :)
Very comprehensive troubleshooting video. The blown fuse section was extremely helpful and the culprit. THANK YOU!
Thanks! I’m glad that you find it helpful:)
Great video! Mine was as simple as the drain being clogged. I vacuumed it out and it works perfect!
I’m glad that it’s helpful for you :)
Very helpful. My issue was blown fuse. It costed only $7.5. Thank you!
You're welcome! Glad that you solved the problem without costing a fortune :)
OUTSTANDING video, comprehensive, to the point and easy to follow. This video should serve as a model for all UA-cam content creators. Immediate start to the sought content, timestamps for the various options, and no obtrusive sales pitches. After going through all of the diagnoses, it turned out to be a flooded drain pan outside. Thank you sir, well done. A like, a comment, ringing the bell, a sub, and I might even mow your lawn if you keep this up.
Thanks for your kind words! I’m glad that it helped you to solve the problem :)
Thank you so much, it was the fuse, you saved us from sleeping in the 80deg heat, thanks!!
Glad that it’s helpful for you :)
I second the previousposter. I didn't know about the fuse until this video, which was my issue, too! You saved me a $150 service call...!
I’m glad that this is helpful for you :) Definitely feels good to be able to solve the problem yourself
Thanks for the video!
Any suggestion for a recurring e74 error? I noted today ac wasn’t on and went through my normal checks. No breaker, dry pan and fuse appeared to be in tacked. I go to UA-cam to search for answers and hear my ac kick on and resolved the problem itself?! Moments later it goes out again but once again resolved on itself?!
Thanks for any advice 🙏
If it keeps coming on and off, it’s likely due to the consensation line not flowing well. You can check out this video on how to check the condensation line: ua-cam.com/video/AiBFL-l0uxY/v-deo.htmlsi=l5dboXvqG975IsW0
Also make sure the air filters are clean.
@@randomhomegadgets Last night I went back through your diagnosis’s and it was in fact the the float switch! The drain pain underneath the unit was bone dry so I didn’t think it could be that but when opening the side panel I noticed some slight puddling inside the unit underneath the coils. Checked the float switch and as soon as I pulled it out the AC kicked on!
You are a rockstar my friend 💪
Great video, thanks for the tips! I have a pretty weird issue - I'm getting this error while the heating is on (and it is only visible through the Nest app). So, once I kick off the heating, it can blow hot air for 5-6 minutes and then stop for 1-2 minutes and after go on again. So, it goes on and off and at the moment it stops I do see E74 error on the app (but the unit display either shows a "Delayed" message or just continues showing that the heating mode is on). Any ideas about what is happening? I do have 2 more Nest Thermostats in my house, and others works without any issues (same wiring at the base and at the HVAC for all units)
This error means that the C wire is not giving enough power to charge the best display. You can use a voltage tester to test the voltage between C wire and the heating wire, should be 24V. If it’s less than that or fluctuate, then there’s a problem with the furnace main board. If the voltage is stable, then there’s a problem with the thermostat itself (may try to swap out the unit display to the ones that you know is working and see if the problem goes away).
@@randomhomegadgets thanks a lot for your reply! I've just measured all my 3 thermostats on each level and they all give me the same readings between C and Rh wires - about 28V (it's fluctuating, but slightly around 27.89-28.01V) I've also tried Google Nest 2nd gen and two units of third-gen and still getting this error...
Hmm, in that case that’s likely some problem with the heater main board. Sorry this is beyond my knowledge level. Probably should check with a HVAC technician.
@@randomhomegadgets no worries! Anyway thanks a lot for your helpful replies! Really appreciate it! 👍
@@artbazildid you end up figuring out what your issue was? Thank you
Thank you... Thank You... Thank you! The best detailed troubleshooting vid on YT for this issue. Saved me $$$.
You are very welcome. I’m glad that you find it useful :)
Diagnosis 5, the power switch to the furnace (which was my case) can break from the connection terminal and either loosen up the wire or totally disconnect from the terminal. Over the years extreme temperature conditions in the attic can cause the plastic crack and separate from the terminal.
Replacing the blown fuse is not a permanent solution. Usually when the fuse blows, that means there’s another problem that keeps reoccurring.
Thanks for your comment. That’s very helpful :)
Amazing video. Need to get this video to the top recommended
Thanks for the kind words. I’m glad the video is helpful for you :)
This was a great video that probably save us hundreds of dollars thank you
Thanks for this video! Looks like my issue was more or less related to diagnosis 1. Either my wife or I may have inadvertently bumped into the power switch on our furnace when bringing out the holiday decorations from the basement 😂 🤦♂️
Thanks for the comment. I'm glad that's an easy fix :P
Music beyond annoying when im failing to fix this damn thing
ez trap for furnace cooling system was clogged with some debris and water setting off the "trap" signal resulting in the E74 error code for my nest. Thanks for the video
Hello - I'm getting intermittent E74 error on cooling. I checked the drain line, Fuse, wiring all seems ok. I need to restart the furnace to get the nest thermostat to work. I have outdoor AC unit and Lennox G61MPV furnace. Any help suggestions pls.
Check to see if you have an in-line float switch. If you have one, open it and see if there’s water backing up in there. It’s likely that the drain pipe is partially clotted and takes a longer time to clear out the water. So when water backs up to the float switch, it shuts off the AC
Thanks for your reply. I don’t have in float switch. I changed thermostat to old honeywell and all works fine. Not sure what to do.
Do packaged units have drain pans/ safety switches? Also where would I find the control board on a packaged unit?
Yes, they should be all inside the packaged unit outside the house. How to get to it depends on the specific units. But usually there should be panel that you can open and look inside.
Thanks for the info. But none of those were my issue. Had the same error code. I pulled the face off and pushed the rh wire around a little and put the cover (interface or what ever it's called) back on and it works now. I think it just needed a hard restart 🤷♂️ I guess. Plus main power went off to the unit. Big storm rolled through.
Thanks for your comment. Probably the error code came up when the main power went out. The Google nest didn’t recognize that the power was back on until you took it out and put it back on again.
Great Video and clear instructions!!! You rock!
Thank you for your kind words. I’m glad that it helped.
Very helpful, thank you for saving me $100's.
Thank you. Found blown fuse.
Glad it helped :)
Thanks, very helpful and informative 🙏
Thanks for your comment. I’m glad that you find it helpful :)
Thanks this help me to fix my
Is the hvac inside or the units outside?
It’s the hvac inside the house
Thanks for your movie. it is clearly and very useful.
I’m gland that it’s helpful for you :)
is the fuse on the furnace inside the house or a/c handler outside the house?
Every house is different, but it’s usually inside the house near the fan blower.
lately every time I turn on the Heater works but after riches for example 72 turns off but again turns back on right away and gives me code E74 I didn't have this problem before
Did all you said but am still having the E74 error code new board new transformer still having same issue it work for a day are two are even couple hrs then bam it's out and E74 help
If it keeps coming on and off, it’s likely due to the consensation line not flowing well. You can check out this video on how to check the condensation line: ua-cam.com/video/AiBFL-l0uxY/v-deo.htmlsi=l5dboXvqG975IsW0
I checked everything and I keep getting the error code. I comes and goes for hours at a time. Works for a while then the error comes back when ever it wants.
Check if you have a in line flow switch. It could be that the drain pipe is partially clotted so the flow switch turn off the HVAC frequently when the water is backed up, then turn it back on when the water is able to get out.
Thank you !!!
You're welcome! I’m glad that it’s helpful for you :)
idek where a fuse is located and it’s freezing this all happens after i tried to use the heater
The fuse is usually at the control board near the furnace/blower unit
@@randomhomegadgets the thermostat isn’t coming on at all now 😭 i didn’t even do anything yet
Yah, since there’s no power going to the thermostat, it will slowly drain out its battery. There’s a micro USB port at the bottom of it, you may use it to charge the battery.
@@randomhomegadgets oh ok thx, it’s probably the fuse, i took it off the wall and no wires were lose, checked the panel too
@@randomhomegadgets
I get a e74 warning every once in a while then within minutes of noticing it the warning goes away.
It could be that your HVAC restarting itself. Sometimes if the HVAC is too hot and not able to vent the air fast enough, it will temporarily shutdown and reset.
Commenting on all these videos with the fix that I found hoping it will help someone.
I simply hit the emergency power light switch to my gas furnace. Once I flipped the power back on, everything was fine. I must have switched it off by mistake moving stuff up and down the basement steps where the switch is.
Thanks for your comment! You are right, need to make sure the power to the furnace is actually on.
Make sure your wife didn’t turn off the switch in the basement
Oh yes that should be the first thing to rule out :P
Ll
I have 8 zones…7 of the thermostats are working…one doesn’t work…e74 code…no power to Rh wire…what do you think it is…I don’t see a drain pan outside by the HVAC system…
Is the E74 all the time or just comes and goes?
Thanks for the video. Headed straight to the auto store got the fuse. Good to go. 🫡
Glad that it’s helpful for you :)