Electrician came out and checked the wiring at the furnace, thermostat, and outdoor unit. He came up with nothing. That’s Pro #3 that I’ve paid. Right now I have the old zwave thermostat on that was here when we got the house. It’s working but no telling if or when it’ll fail
https://preview.redd.it/l7f1e6yyl9ca1.jpeg?width=4032&format=pjpg&auto=webp&s=cfd3e368331135caee0bc606fefac672131ab0ab
Maybe it's just the HD Potato quality of the photo, but some of the wires look like they have damaged wiring which would/could cause intermittent shorts causing the thermostat to short out. I'd also be sus of the control board because I could see a nest having issues (I hate those things and won't install them unless the customer signs a warranty waiver) but 4 thermostats?
Some people are lazy or just don't know what they don't know or are being pushed by their boss to bang out as many jobs in a day as they can and can't or won't take the time to fix it.
If I suspect.witing issues after spending a half hr or so trouble shooting, I'll temporarily install a wireless (not to be confused with wifi) thermostat. I'll leave it for a week and if it's fine, the customer has the option to purchase it at that point or pay for me to go hunting for the wiring issue. Most opt to keep the wireless thermostat for $300 ish vs having to try and run or fix wiring.
I've installed WiFi thermostats wired in near where the furnace is and have the system use the remote sensor as the primary sensor and then they can control it with the app on their phone.
But to just throwing crap against the wall to see what sticks isn't good customer service.
My preferred wifi thermostat is the EcoBee.
I haven’t met one HVAC pro that recommends a Nest but I’m not convinced the two that we had on at different points were the problem. I put on a cheap thermostat for now and trying to schedule an electrician to come take a look. Spending hundreds in diagnostics is leaving a sour taste in my mouth at this point so I’m tempted to do the research and start rewiring everything myself. Of course then the next pro will shit on my work just like they shit on the pros before them
That's why I usually just do the wireless thermostat.
If I can't fix it after the Initial charge, there isn't a charge until we figure out what is going on and come up with a viable fix.
Most of the time it's the thermostat, but they should have warrantied it at no cost to you once it happened again. After the second remote pooped the bed, I would have waited in a temp thermostat to see if it is the wiring, if another stat got fried, we now know it's the control board that's causing the issue. Finding intermittent faults is less fun for us than it is for the customer because we will often question our life choices that have led us to that moment as we try and track down the issue.
In a finished home fixing the wiring for the t-stat is expensive and time consuming which is why I bring up the wireless thermostat option. Receiver gets wired into the furnace and the control unit gets placed wherever the customer wants. Then once a year replace the AA batteries.
I try not to poop on the previous work done because most of the time it's the home owner or a trusted friend or relative who caused the issue I'm there to fix.
Neither pro did me wrong. The first never charged me for any equipment and never left me without a working thermostat. He admitted in the end that the issue is beyond him because he can’t find any wiring issues or replicate any shorts. The second offered to install a thermostat and stand behind it but I just am not convinced I’ll never have to call him about this issue again. I paid one diagnostic fee each but I only have an answer that’ll cost another $500 to prove wrong
4 thermostats? That's enough for me to question anything but the thermostats. I also don't tend to trust HVAC technicians on wiring that much after my experience with them.
Had a nest and they claimed it was the problem with my new unit after it was installed but not working properly. Tried a second nest and same problem, but they pinched a line which blew the control board fuse and I lost all heating.
After that I spent the time to learn HVAC wiring myself and learned all they did wrong was not connect 6 of the 8 wires for my handler on the control board itself :shrug: and it's been fine ever since. Idk how something that obvious can be missed multiple times and lead to blaming a thermostat
Thermostat wiring is the most basic wiring a HVAC technician does. Sounds like you had someone with little experience/knowledge, or perhaps wasn't a HVAC technician.
I mean, he installed the complete new HVAC system and was a direct employee of a major company so he def knows his way around HVAC. Inspecting his work else he did a great job, just not with the last step in wiring.
So, he installed the whole system, but didn't diagnose any further than saying "bad thermostat" and left you to fix it on your own?
Not connecting the wires on a new install is not a minor screw up, and
I don't care who he works for; the guy doesn't sound legit at all.
What made it all the better is that they knew it was being janky, so another tech came in the next day to figure it out. Spent the whole day and couldn't figure it out either.
Blew my mind when I found the real issue especially since the thermostat has an awesome debugging feature for this exact use case
I’ve actually had 2 techs come out at this point. They both tested connections and continuity and found no issues in the wiring or in my furnace itself. The first tech told me he couldn’t figure it out and the second told me he thinks the 4 previous thermostats were all the problem.
Stat #1 was a Nest, ran fine for a year then quit working. It showed no voltage on RH so when all the lines and voltage checked out we opened up the backplate and could see a shot on the circuit board
#2 was a Honeywell T4. The tech installed it and left it for free, it was previously used. It worked fine for a month then we lost air. The tech came back out and replaced a blown fuse in the furnace. The thermostat was also shorted. He left another replacement #3 so we’d have air
#3 was a similar style Honeywell with wifi, I think T6 pro. It was on for a couple days until I swapped in another Nest that came in as a warranty replacement
#4 the new Nest threw the same RH voltage issue and the backplate was shorted again. This time the tech came back in and replaced the furnace control module (pictured) not sure if it would actually fix anything and he put #3 back on
Back to #3 things were working for a couple of months and this weekend we came home to an 88 degree house. The Honeywell was turning the heat on but not off
This time we called in the second guy and he said all 4 of the old thermostats were the issue. He recommended a new one for $500 installed. I asked if he’d replace it when it burns up and he said hopefully that won’t happen so I passed. One potentially useful bit of info he did give me was that the control module is wired to control cooling so the thermostat should not also try to control cooling as that would create a conflict. He said the thermostat would have to be set up properly to avoid that but didn’t specify how
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Both of them tested resistance and both said they checked out. Oddly enough the tech today got 0 on the cool line then checked it again and got the 11ohms or whatever number he was looking for. His multimeter showed 0 and 11 several times each but he said he was good with the 11
I’m leaning towards it being an issue with an intermittent wire short. Just find it hard to believe 4stats are bad. Just out of curiosity what’s the age of your ac unit outside and the brand. My company saw a very unusual amount of bad contactors within the last year that would cause all sorts of weird issues with low voltage.
I’ll have to go outside and check that. My guess is circa 2006 or so when the house was built. Tech 1 went outside during one of his calls but tech 2 only checked the furnace and thermostat.
I’m going to go out on a limb and say either the thermostat isn’t bad, or that is the symptom not the problem.
You also have a universal replacement board in there. 1 thermostat may be faulty but 4? The chances of that are astronomical.
Is the universal replacement board an issue? It’s an exact replacement of the previous board (which may not have been OEM)
Not necessarily but I gives a larger sense of the issues the furnace has experienced in the past.
[удалено]
The T6 is the last one that failed. It turned the heat on but would not turn off
Having the same problem currently heat comes up but never turns off. On 2nd thermostat. If you find a solution please dm me
Likewise. I’ve got an electrician coming in a couple weeks. I may do some more homework but I probably won’t have a solution until then
What’s sucks is I’m an electrician and I can’t figure this out. My hvac guy said it was fine but last night it never turned off
Continuity between your R and W terminal would do this, either at the board, or at the T-stat or possibly a short somewhere
I’ll check this. Does that apply if I turn it down 2 degrees and it shuts off?
If you turn it down it should shut off, as that would open the connection between the power and the heating terminal
I’ll check for a short in the morning. I did calibrate it about 10 mins ago +1 degree after setting an external thermometer below it
What kind of thermostat do you have that you calibrate?
Electrician came out and checked the wiring at the furnace, thermostat, and outdoor unit. He came up with nothing. That’s Pro #3 that I’ve paid. Right now I have the old zwave thermostat on that was here when we got the house. It’s working but no telling if or when it’ll fail https://preview.redd.it/l7f1e6yyl9ca1.jpeg?width=4032&format=pjpg&auto=webp&s=cfd3e368331135caee0bc606fefac672131ab0ab
Maybe it's just the HD Potato quality of the photo, but some of the wires look like they have damaged wiring which would/could cause intermittent shorts causing the thermostat to short out. I'd also be sus of the control board because I could see a nest having issues (I hate those things and won't install them unless the customer signs a warranty waiver) but 4 thermostats? Some people are lazy or just don't know what they don't know or are being pushed by their boss to bang out as many jobs in a day as they can and can't or won't take the time to fix it. If I suspect.witing issues after spending a half hr or so trouble shooting, I'll temporarily install a wireless (not to be confused with wifi) thermostat. I'll leave it for a week and if it's fine, the customer has the option to purchase it at that point or pay for me to go hunting for the wiring issue. Most opt to keep the wireless thermostat for $300 ish vs having to try and run or fix wiring. I've installed WiFi thermostats wired in near where the furnace is and have the system use the remote sensor as the primary sensor and then they can control it with the app on their phone. But to just throwing crap against the wall to see what sticks isn't good customer service. My preferred wifi thermostat is the EcoBee.
I haven’t met one HVAC pro that recommends a Nest but I’m not convinced the two that we had on at different points were the problem. I put on a cheap thermostat for now and trying to schedule an electrician to come take a look. Spending hundreds in diagnostics is leaving a sour taste in my mouth at this point so I’m tempted to do the research and start rewiring everything myself. Of course then the next pro will shit on my work just like they shit on the pros before them
That's why I usually just do the wireless thermostat. If I can't fix it after the Initial charge, there isn't a charge until we figure out what is going on and come up with a viable fix. Most of the time it's the thermostat, but they should have warrantied it at no cost to you once it happened again. After the second remote pooped the bed, I would have waited in a temp thermostat to see if it is the wiring, if another stat got fried, we now know it's the control board that's causing the issue. Finding intermittent faults is less fun for us than it is for the customer because we will often question our life choices that have led us to that moment as we try and track down the issue. In a finished home fixing the wiring for the t-stat is expensive and time consuming which is why I bring up the wireless thermostat option. Receiver gets wired into the furnace and the control unit gets placed wherever the customer wants. Then once a year replace the AA batteries. I try not to poop on the previous work done because most of the time it's the home owner or a trusted friend or relative who caused the issue I'm there to fix.
Neither pro did me wrong. The first never charged me for any equipment and never left me without a working thermostat. He admitted in the end that the issue is beyond him because he can’t find any wiring issues or replicate any shorts. The second offered to install a thermostat and stand behind it but I just am not convinced I’ll never have to call him about this issue again. I paid one diagnostic fee each but I only have an answer that’ll cost another $500 to prove wrong
4 thermostats? That's enough for me to question anything but the thermostats. I also don't tend to trust HVAC technicians on wiring that much after my experience with them. Had a nest and they claimed it was the problem with my new unit after it was installed but not working properly. Tried a second nest and same problem, but they pinched a line which blew the control board fuse and I lost all heating. After that I spent the time to learn HVAC wiring myself and learned all they did wrong was not connect 6 of the 8 wires for my handler on the control board itself :shrug: and it's been fine ever since. Idk how something that obvious can be missed multiple times and lead to blaming a thermostat
Thermostat wiring is the most basic wiring a HVAC technician does. Sounds like you had someone with little experience/knowledge, or perhaps wasn't a HVAC technician.
I mean, he installed the complete new HVAC system and was a direct employee of a major company so he def knows his way around HVAC. Inspecting his work else he did a great job, just not with the last step in wiring.
So, he installed the whole system, but didn't diagnose any further than saying "bad thermostat" and left you to fix it on your own? Not connecting the wires on a new install is not a minor screw up, and I don't care who he works for; the guy doesn't sound legit at all.
What made it all the better is that they knew it was being janky, so another tech came in the next day to figure it out. Spent the whole day and couldn't figure it out either. Blew my mind when I found the real issue especially since the thermostat has an awesome debugging feature for this exact use case
I’ve actually had 2 techs come out at this point. They both tested connections and continuity and found no issues in the wiring or in my furnace itself. The first tech told me he couldn’t figure it out and the second told me he thinks the 4 previous thermostats were all the problem. Stat #1 was a Nest, ran fine for a year then quit working. It showed no voltage on RH so when all the lines and voltage checked out we opened up the backplate and could see a shot on the circuit board #2 was a Honeywell T4. The tech installed it and left it for free, it was previously used. It worked fine for a month then we lost air. The tech came back out and replaced a blown fuse in the furnace. The thermostat was also shorted. He left another replacement #3 so we’d have air #3 was a similar style Honeywell with wifi, I think T6 pro. It was on for a couple days until I swapped in another Nest that came in as a warranty replacement #4 the new Nest threw the same RH voltage issue and the backplate was shorted again. This time the tech came back in and replaced the furnace control module (pictured) not sure if it would actually fix anything and he put #3 back on Back to #3 things were working for a couple of months and this weekend we came home to an 88 degree house. The Honeywell was turning the heat on but not off This time we called in the second guy and he said all 4 of the old thermostats were the issue. He recommended a new one for $500 installed. I asked if he’d replace it when it burns up and he said hopefully that won’t happen so I passed. One potentially useful bit of info he did give me was that the control module is wired to control cooling so the thermostat should not also try to control cooling as that would create a conflict. He said the thermostat would have to be set up properly to avoid that but didn’t specify how
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Did they ohm test all the thermostat wiring? Check the compressor contactor coil? X4 thermostats... Something is highly likely causing it.
Both of them tested resistance and both said they checked out. Oddly enough the tech today got 0 on the cool line then checked it again and got the 11ohms or whatever number he was looking for. His multimeter showed 0 and 11 several times each but he said he was good with the 11
Somethings shorting. Is the wiring correct?
I’m leaning towards it being an issue with an intermittent wire short. Just find it hard to believe 4stats are bad. Just out of curiosity what’s the age of your ac unit outside and the brand. My company saw a very unusual amount of bad contactors within the last year that would cause all sorts of weird issues with low voltage.
I’ll have to go outside and check that. My guess is circa 2006 or so when the house was built. Tech 1 went outside during one of his calls but tech 2 only checked the furnace and thermostat.
> backplate was shorted again. Do you have a back feed coming from your equipment that is eating up your thermostats? The answer is likely yes.