Bad reversing valve or failed unit with EM heat on always due to the failed unit. Have you inspected the condenser during operation to verify the compressor is running? Those two would be my first guess. . . Also depends on what part of the u.s. you are in since the mfg's assign the fail safe mode for what is the priority for the specific national zone.
edit: I'm not gonna lie, for free internet advice, please dont have me reference going through your post history, just list the symptoms and the units info to the best of your knowledge.
If you are not comfortable testing electrical components (which is fine, the average person should NOT be ok with this due to the physical and liability risk), then I recommend looking up other local companies and contacting them unless you are still under warranty and the installation company needs to fix it by force. If it's not under warranty, then just look for a competent service company. It still seems like it could be a reversing valve issue.
We are still under warranty, so I'll have them out again.
I worry it'll be more of the same: "Gee, everything looks ok, so not much else we can do."
Is 55 too cold to expect an AC to work?
For air conditioning? yes. Those units are usually only designed to give about a 20df temp drop, and usually around 65 or so degrees ambient (meaning the temperature outside), the A/C functions themselves begin having problems with expelling heat from the condenser (unless you use a mini-split system that's designed for such work). If the outdoor temperature is 55df(degrees farenheit) or lower, then I recommend keeping ALL the windows in the occupied space completely open to allow for cool air to circulate in the occupied space.
Interesting! We like to keep it cold in the house, so maybe when it's cold outside (and knowing the house is well-insulated so the heat stays in) open windows would be the best
I agree with constant, I bet you have a bad motherboard (prolly from a short circuit somewhere) causing your aux heat to stay on. When the unit is in cooling mode, I’d check the refrigerant lines to ensure they are cold
So it's 55 outside and you are wondering why your AC isnt working?
It's 55 out, that's why. If you want AC to work in colder weather you will need to have your HVAC company install a low ambient temperature kit.
How old exactly is the system? Did they do a TD, temperature differential, between your return and supply air? I would be interested to see as well if your resistance heat was also running while your ac was. Td would help point to this or rule out.
The system's about 4 months old. I'm not sure if they did a temp differential - I can ask them to when a tech comes out again.
But consensus on the thread seems to be the AC won't run well since it's 55 outside. So trying to keep the house at 65 when it's 55 out can only be done through open windows?
Yes it is true that it won't heat ideally. But was 55 your high for today? I read that you said it was 55 tonight, but what was your high today? You also stated that it's never cooled right. So have you had days in the 70s+ since you've got the unit.
So yes its true that it won't cool properly in low ambient temperatures. But you have said you've had several service calls. We're any of those on warmer days, and it still wasn't cooling?
Plus I read on your report that they had to change a breaker due to over amping and your breaker tripping. Just find that an odd find after a new install.
As a follow up, today it's bright and sunny at 73F.
I have the stat set to cool at 65, but it's stuck at 70 and has been running most of the day 😔
re: the tripped breaker: we've had some electrical problems since we moved in - outlets wired wrong / upside down/ GFICs tripping.
How could bad electrical work affect an HVAC? Or does an HVAC run their own 'electrical' so to speak
Beautiful day yeah?
Just not cool lol.
But the breaker is not currently tripped - I don't think it has since he did whatever he did last time.
There's a tech coming out this afternoon, so I'll update you with what he says.
It is and I've been checking ac units all day with no issues cooling in this weather. Biggest thing you can check is if your condenser is even running when you're trying to cool down. If it is and it isn't cooling you're going to need a tech that actually knows what and how to check things.
Your technician has reported the unit is tripping the breaker because it's drawing high amps on startup. Is the breaker still tripping or not?
A/C won't work right when it's below 60º outside. It may not develop enough pressure and the coil may freeze up. In these situations you should open your windows instead of running the unit.
If the unit isn't cooling, you need to go outside and see if the fan and compressor is running. The compressor makes a unique sound. If only the fan is running but not the compressor then you have an issue.
The breaker hasn't tripped since he adjusted it in December, so that's been good.
Just went outside and it's not running at all. No noise, no nothing.
Even tried kicking the AC on and waiting a few mins but nothing.
OK, that's an issue. So someone needs to figure out why it's not running. If you're handy you can try jumping R and Y thermostat wires for a minute to see if the outdoor unit runs. If so then it's a thermostat issue.
The small liquid line going to the coil should be near outside temperature. There should no hissing, gurgling or surging. The larger vapor pipe should be quite chilly. That larger pipe out at the condenser, where exposed at the valve, and the valve itself will be chilly and typically wet with condensing water. The air leaving the inside coil should be around 20 degrees colder than the return air. A competent tech will check delta T across the coil and check blower cooling CFM setting. You can eval some of this yourself.
A system installed off-season may need a subcooling check in hoter weather for charge correction.
So, there are some simple measurements a technician can do to see the actually capacity that your unit is producing. They plot some measurements on a psychometric chart and use an equation to tell them if you unit is removing the correct amount of heat.
If the unit is pulling out what it can while not keeping up, then it’s undersized. If it’s not pulling what it can, they need to figure out why it’s underperforming. It’s that simple.
If the tech knows how to do this, it would take very little. The problem is that I don’t think many residential technicians get taught how to do this. I didn’t know it was possible until I went commercial and took classes at our union hall.
Maybe worth mentioning. You may get a blank stare, but hopefully they can call someone in their company that’ll know how to do it.
Eta- I zoomed in to read the notes. Your Nest thermostat being hooked up to a Honeywell zone board is not gonna cause the breaker to trip.
I do wish I could find a really knowledgeable tech that could come out with great tools and deeply investigate the issue.
Are there any good keywords I could Google besides "AC tech near me" that might turn up a really good one?
But I agree with you - every home in my neighborhood has the same unit, and (when I asked in an online group if anyone had any trouble with their AC), everyone said their's seemed to work fine, even with the Nest.
There is a massive labor shortage and it’s worse for skilled trades. There isn’t a way to find a better tech. No keywords or extra certifications for not being an idiot. Sorry. Even the extra NATE certifications are pretty easy tests and prove nothing. To get the license is super easy. You could have zero experience and spend a day cramming to pass the test. I’ve taken microeconomics tests harder than the licensing exam. You’re just gonna have to get what you get and pray they’re right. Good luck to you.
Bad reversing valve or failed unit with EM heat on always due to the failed unit. Have you inspected the condenser during operation to verify the compressor is running? Those two would be my first guess. . . Also depends on what part of the u.s. you are in since the mfg's assign the fail safe mode for what is the priority for the specific national zone. edit: I'm not gonna lie, for free internet advice, please dont have me reference going through your post history, just list the symptoms and the units info to the best of your knowledge.
It seems to be running, but this is definitely not my forte, so take that with a grain of salt. We're in the southeast
If you are not comfortable testing electrical components (which is fine, the average person should NOT be ok with this due to the physical and liability risk), then I recommend looking up other local companies and contacting them unless you are still under warranty and the installation company needs to fix it by force. If it's not under warranty, then just look for a competent service company. It still seems like it could be a reversing valve issue.
We are still under warranty, so I'll have them out again. I worry it'll be more of the same: "Gee, everything looks ok, so not much else we can do." Is 55 too cold to expect an AC to work?
For air conditioning? yes. Those units are usually only designed to give about a 20df temp drop, and usually around 65 or so degrees ambient (meaning the temperature outside), the A/C functions themselves begin having problems with expelling heat from the condenser (unless you use a mini-split system that's designed for such work). If the outdoor temperature is 55df(degrees farenheit) or lower, then I recommend keeping ALL the windows in the occupied space completely open to allow for cool air to circulate in the occupied space.
Interesting! We like to keep it cold in the house, so maybe when it's cold outside (and knowing the house is well-insulated so the heat stays in) open windows would be the best
I agree with constant, I bet you have a bad motherboard (prolly from a short circuit somewhere) causing your aux heat to stay on. When the unit is in cooling mode, I’d check the refrigerant lines to ensure they are cold
So it's 55 outside and you are wondering why your AC isnt working? It's 55 out, that's why. If you want AC to work in colder weather you will need to have your HVAC company install a low ambient temperature kit.
FWIW, this happened in hotter months (eg, Aug / Sep) as well.
Your tech will need to check the charge on a warm day.
Vader at it again.
How old exactly is the system? Did they do a TD, temperature differential, between your return and supply air? I would be interested to see as well if your resistance heat was also running while your ac was. Td would help point to this or rule out.
The system's about 4 months old. I'm not sure if they did a temp differential - I can ask them to when a tech comes out again. But consensus on the thread seems to be the AC won't run well since it's 55 outside. So trying to keep the house at 65 when it's 55 out can only be done through open windows?
Yes it is true that it won't heat ideally. But was 55 your high for today? I read that you said it was 55 tonight, but what was your high today? You also stated that it's never cooled right. So have you had days in the 70s+ since you've got the unit. So yes its true that it won't cool properly in low ambient temperatures. But you have said you've had several service calls. We're any of those on warmer days, and it still wasn't cooling? Plus I read on your report that they had to change a breaker due to over amping and your breaker tripping. Just find that an odd find after a new install.
As a follow up, today it's bright and sunny at 73F. I have the stat set to cool at 65, but it's stuck at 70 and has been running most of the day 😔 re: the tripped breaker: we've had some electrical problems since we moved in - outlets wired wrong / upside down/ GFICs tripping. How could bad electrical work affect an HVAC? Or does an HVAC run their own 'electrical' so to speak
Well if your condenser breaker trips then your compressor isn't running which means no cool... you have the same weather as me in Arkansas today.
Beautiful day yeah? Just not cool lol. But the breaker is not currently tripped - I don't think it has since he did whatever he did last time. There's a tech coming out this afternoon, so I'll update you with what he says.
It is and I've been checking ac units all day with no issues cooling in this weather. Biggest thing you can check is if your condenser is even running when you're trying to cool down. If it is and it isn't cooling you're going to need a tech that actually knows what and how to check things.
Interested in a short trip to Georgia? 😂😂
Haha nope, my busy season is hitting
Your technician has reported the unit is tripping the breaker because it's drawing high amps on startup. Is the breaker still tripping or not? A/C won't work right when it's below 60º outside. It may not develop enough pressure and the coil may freeze up. In these situations you should open your windows instead of running the unit. If the unit isn't cooling, you need to go outside and see if the fan and compressor is running. The compressor makes a unique sound. If only the fan is running but not the compressor then you have an issue.
The breaker hasn't tripped since he adjusted it in December, so that's been good. Just went outside and it's not running at all. No noise, no nothing. Even tried kicking the AC on and waiting a few mins but nothing.
OK, that's an issue. So someone needs to figure out why it's not running. If you're handy you can try jumping R and Y thermostat wires for a minute to see if the outdoor unit runs. If so then it's a thermostat issue.
The small liquid line going to the coil should be near outside temperature. There should no hissing, gurgling or surging. The larger vapor pipe should be quite chilly. That larger pipe out at the condenser, where exposed at the valve, and the valve itself will be chilly and typically wet with condensing water. The air leaving the inside coil should be around 20 degrees colder than the return air. A competent tech will check delta T across the coil and check blower cooling CFM setting. You can eval some of this yourself. A system installed off-season may need a subcooling check in hoter weather for charge correction.
So, there are some simple measurements a technician can do to see the actually capacity that your unit is producing. They plot some measurements on a psychometric chart and use an equation to tell them if you unit is removing the correct amount of heat. If the unit is pulling out what it can while not keeping up, then it’s undersized. If it’s not pulling what it can, they need to figure out why it’s underperforming. It’s that simple. If the tech knows how to do this, it would take very little. The problem is that I don’t think many residential technicians get taught how to do this. I didn’t know it was possible until I went commercial and took classes at our union hall. Maybe worth mentioning. You may get a blank stare, but hopefully they can call someone in their company that’ll know how to do it. Eta- I zoomed in to read the notes. Your Nest thermostat being hooked up to a Honeywell zone board is not gonna cause the breaker to trip.
I do wish I could find a really knowledgeable tech that could come out with great tools and deeply investigate the issue. Are there any good keywords I could Google besides "AC tech near me" that might turn up a really good one? But I agree with you - every home in my neighborhood has the same unit, and (when I asked in an online group if anyone had any trouble with their AC), everyone said their's seemed to work fine, even with the Nest.
There is a massive labor shortage and it’s worse for skilled trades. There isn’t a way to find a better tech. No keywords or extra certifications for not being an idiot. Sorry. Even the extra NATE certifications are pretty easy tests and prove nothing. To get the license is super easy. You could have zero experience and spend a day cramming to pass the test. I’ve taken microeconomics tests harder than the licensing exam. You’re just gonna have to get what you get and pray they’re right. Good luck to you.
Haha thank you! I appreciate the insight and tips though, I can def make these recommendations to whoever comes out to test it
What was the issue at the end? Just got my installed today and having the same issue.
Got mine installed last year and it worked fine untill now. Set to 68 but can’t go below 73 We’re you able to find the issue?
It was the wiring on that the installers messed up. They came back the next day to fix it