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2xPowerwall whole house backup - HVAC sure start problem

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That's not new technology, all this proves is these companies oversell these systems and put high hopes on a "soft start" they have usually not tested on specific AC compressors hoping it works and when it doesn't the customer ends up dealing with the problems like you have. My recommendation is to remove the sure start get Tesla to install a 3rd PW on their dime especially if it is in your contract that the AC will work with the system they promised. I'm in a similar boat and waiting to hear back from my installer. Sadly when these companies know they are in the wrong they seem to drag their feet as long as they can.
 
I thought I'd post a followup to this. I initially thought the SureStart was working correctly after the 2nd installation. But it turns out my AC was working intermittently and started throwing error messages. I won't go into the gory details of going through a heat wave with a malfunctioning AC unit and waiting weeks for Tesla to address it.
I decided to take matters into my own hands and contacted Hyper Engineering directly. It turns out my compressor is wired to allow reverse running and SureStart is not compatible with it. They said this is the first system they've come across with this "fairly recent technology" (my outside unit was installed in 2008).
I've told Tesla this and asked them what their plan forward is but I haven't heard back.
I've attached a description of the system that Hyper Engineering sent to me.
Ah, your compressor is not the common scroll type. If you can live with only have one speed, the reversing circuit could probably be bypassed to allow the sure start to work. Depending on the setup, it might work for dual speed. Can you (re?)post the model and/or wiring diagram?
 
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That's not new technology, all this proves is these companies oversell these systems and put high hopes on a "soft start" they have usually not tested on specific AC compressors hoping it works and when it doesn't the customer ends up dealing with the problems like you have. My recommendation is to remove the sure start get Tesla to install a 3rd PW on their dime especially if it is in your contract that the AC will work with the system they promised. I'm in a similar boat and waiting to hear back from my installer. Sadly when these companies know they are in the wrong they seem to drag their feet as long as they can.
The last technician that came out couldn't get it to work (he wasn't an HVAC guy). I told him to remove the SureStart and rewire the compressor per the factory diagram until they figure it out. Then the AC wouldn't start at all. He said the outside unit must be bad and it could be just a coincidence that problems started happening when they installed the SureStart. He said that I need to call a HVAC repair service and get it fixed. He said the HVAC repair service would have to state that the SureStart caused the problem if I wanted to get reimbursed. I called a local HVAC service and asked them what they would do (while the tech was still here). They said they would diagnose what the bad component(s) was but wouldn't state what caused the problem.

I compared the factory wiring diagram to what the tech rewired and noticed that there was a wire missing going to the start capacitor. I asked the tech why he didn't install that wire. He said he rewired it per a picture that was taken by the first tech prior to installing the SureStart. I looked at the picture and noticed that there was a disconnected wire so it couldn't be before the first tech started the job. The tech said that was all he could do and needed to get to another job. I made a wire up after the tech left and connected per the wiring diagram. The unit now runs like it did before Tesla touched it.

I don't know if I could get Tesla to install a 3rd Powerwall since I'm getting a SGIP incentive and that might not comply with the terms of the agreement.
 
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Seems like Tesla is just as negligent and incompetent as third party companies. Let me guess without even knowing your wiring diagram they forgot to connect the yellow wire that goes from the Contactor(23) to the run capacitor (common).

You got lucky they didn't damage your system, they fried my run capacitor and the HVAC company came out and sure enough the sure start was blown too b/c they miss wired it 3 different times with 3 different crews. I paid the HVAC bills but they owe me and the HVAC company stated it was due to miss wiring so they know they are liable.

I will never recommend PW's to anyone who wants a backup system, get a Generac Generator and problem solved.
 
Seems like Tesla is just as negligent and incompetent as third party companies. Let me guess without even knowing your wiring diagram they forgot to connect the yellow wire that goes from the Contactor(23) to the run capacitor (common).

You got lucky they didn't damage your system, they fried my run capacitor and the HVAC company came out and sure enough the sure start was blown too b/c they miss wired it 3 different times with 3 different crews. I paid the HVAC bills but they owe me and the HVAC company stated it was due to miss wiring so they know they are liable.

I will never recommend PW's to anyone who wants a backup system, get a Generac Generator and problem solved.
That is a particularly harsh statement. I would say it differently - If you absolutely must have A/C backed up on Powerwalls, plan on upgrading to a variable speed A/C compressor.
 
You can't understand the frustration until you have had my experience. I stand by my statement about PW, from the absurd phase shifting with a PV system, buggy gateway software, and lack of info from Tesla on details to name a few it is a system I can never recommend to anyone moving forward.

Also you can't just upgrade from a single stage compressor to a variable stage or 2-stage without replacing the whole system which averages about $30K. You also can't just upgrade to a more efficient SEER single stage compressor and expect the RLA/LRA to drop enough to make a difference.

The reality is these companies including Tesla need to stop falsely advertising and making promises to customers for a quick buck. The industry and these companies have no checks and balances or accountability. Coincidentally customers need to do their own due diligence, but when the "experts" tell you it should work what is the average customer expected to do. The only saving grace I have is all my communication is documented and it's in my contract.

Save yourself the headache and get a tried and true proven generator or else know what you will get with a PW as your backup system.
 
Boy, I'm glad Tesla does not install here. I'd have gone with Tesla because I loved my Roadster and I love my Model 3. I even wrote to Tesla when I was planning my move, asking for information about getting solar here, and got no reply. So I used a local solar installer recommended by my realtor. The installer told me my A/C probably wouldn't start without grid power. He told me he'd heard of soft-start adapters but didn't know if that would work or not. After the installation, when I tried to get a soft-start adapter, the air conditioner people told me to talk to an electrician and the electrician told me to talk to an air conditioner outfit. Nobody wanted to touch it.

Now, thanks to you guys, I know why.

My Powerwalls are working perfectly as advertised and promised. I draw a tiny amount of power from the grid each time the A/C starts and when the power is down my A/C won't start. All what I was told to expect.
 
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I'll go ahead and rant about the first part of my HVAC experience. I have gotten very soured on the way Tesla handles things.

I didn't realize my AC wasn't working correctly until the following Friday afternoon during a heat advisory. It was too late to call Tesla so I waited until Monday morning since someone was supposed to come Monday morning anyway to support the county inspection. Even though I called first thing Monday morning they couldn't guarantee the person that showed up could do anything. Sure enough, the guy the showed up wasn't even an electrician (not sure what he was supposed to do if the inspector found something he didn't like). As soon as I found that out I called Tesla and was on hold for about an hour (I was multitasking). I decided to do the callback option and got a callback early in the afternoon. They told me they needed to connect me to a different department and was put on a long hold again. I decided to leave a message (that line didn't have a callback option). I was transferred to a mailbox that was full with no way to get back to where I was in line so I had to start over. I finally got through late in the afternoon.
The person said I needed to sign a service agreement since the job had been "completed". I objected since my inspection hadn't been signed off, I don't have PTO, and my AC really wasn't working correctly from day one but they said that was the only way. I agreed and they said the form would show up under my account for me to digitally sign. There wasn't anything there Tuesday so I called Tesla again. They couldn't get the form to show up under my account so they said they would send me an Adobe Sign document. They said that would take a special person to send it to me. I finally got the document Wednesday morning and promptly signed it. I called them after that to make sure they got it (they didn't - I had to sign it again even though I got an email acknowledging I approved the first one) and to find out what happens next. They said it will take 24 hours for the "department" to review the form and approve it (it's their one page form - all I did was sign it in one place) and then they can get me transferred to scheduling. I called scheduling on Thursday. They said they didn't have the form yet so they couldn't schedule me. I called again on Friday and they said they still didn't have the form. After a while they determined they did have the form but couldn't see it in their system. I finally got an acknowledgement Friday evening that they could see the form and would work on getting me on the schedule. I got an email notice Monday morning that they would send a tech out the following Monday morning. This was the tech that wasn't a HVAC specialist and left with the AC completely inoperable.
 
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Just an inexcusable experience, I've had similar experience calling Tesla trying to get through. Their level one customer service is no better than calling offshore support for some of these other companies who try to squeeze profits. Just waste your time and have no clue what they are talking about even L2 is clueless most of the time. when a level 2 Tesla rep tells you to look at Reddit for an answer that's pathetic.

Would love to see Elon call up with his own tech support as a regular customer and see how he gets treated.
 
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Save yourself the headache and get a tried and true proven generator or else know what you will get with a PW as your backup system.

This is not quite correct. The issue remains with generators. Just as you may need additional PWs to start your AC, you'll need a more powerful generator to start your AC. Your house may only need a 15kW generator without AC, but with AC, might need a 22kW generator. The big difference is the generator will cost a fraction of the price.
 
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It is very true what I stated, and you are correct in your assessment. Obviously you have to compare apples to apples in terms of KWh comparing generator vs PW. The cost is not even comparable. A 22KWh Honeywell/Generac from Costco goes on sale for $4200 time to time. I bought one had it ready to go but my solar company convinced me to go the battery route promising the AC will work. The PWs more than double the cost after rebate and tax credit. Only reason I opted to go the battery route personally is in Cali there is quakes, if they shut the gas down than you are out of luck unless you have propane backup and that is not an option with HOAs.

All the 20KWh+ Generators come with a ATS designed specifically to handle AC inrush loads, a soft start built into the transfer switch. That generator would have ran the whole house with AC no problem and more and it cost less than one PW.

Again people need to do their own due diligence and not fall for the sales pitch no matter what Tesla or anyone says, same with Generators, there is some minor maintenance like oil changes and valve lash adjustment, if you are handy it's not a big deal you can do it yourself or pay your installer. At the end of the day there is trade offs. If you have the luxury of buying either for just emergencies which was my need you have to honestly ask yourself several questions about the use case and look at the pros and cons.
 
That is a particularly harsh statement. I would say it differently - If you absolutely must have A/C backed up on Powerwalls, plan on upgrading to a variable speed A/C compressor.
It looks like the Copeland SecureStart is a rebranded HyperEngineering SureStart. On the product's website, it shows a list of compatible compressors. Is there any reason the SecureStart with a compatible compressor wouldn't be able to handle being backed up by Powerwalls?
SecureStart™ for Copeland Compressors | Emerson US
 
It is very true what I stated, and you are correct in your assessment. Obviously you have to compare apples to apples in terms of KWh comparing generator vs PW. The cost is not even comparable. A 22KWh Honeywell/Generac from Costco goes on sale for $4200 time to time. I bought one had it ready to go but my solar company convinced me to go the battery route promising the AC will work. The PWs more than double the cost after rebate and tax credit. Only reason I opted to go the battery route personally is in Cali there is quakes, if they shut the gas down than you are out of luck unless you have propane backup and that is not an option with HOAs.

All the 20KWh+ Generators come with a ATS designed specifically to handle AC inrush loads, a soft start built into the transfer switch. That generator would have ran the whole house with AC no problem and more and it cost less than one PW.

Again people need to do their own due diligence and not fall for the sales pitch no matter what Tesla or anyone says, same with Generators, there is some minor maintenance like oil changes and valve lash adjustment, if you are handy it's not a big deal you can do it yourself or pay your installer. At the end of the day there is trade offs. If you have the luxury of buying either for just emergencies which was my need you have to honestly ask yourself several questions about the use case and look at the pros and cons.

I had a Generac 11kW on my old house. Installed about six years ago, it had a load shedding capability for two AC (I only had one) but no soft-start. Never really needed the backup over that period so don't know if the AC would have worked. As I look back on specs, probably would not have worked. I didn't understand that before now.

I looked on Generac web site and called them. No answer to your point about 20kW+ ATS having soft-start built in. Can you post link for that? Thanks.
 
I'll go ahead and rant about the first part of my HVAC experience. I have gotten very soured on the way Tesla handles things.

I didn't realize my AC wasn't working correctly until the following Friday afternoon during a heat advisory. It was too late to call Tesla so I waited until Monday morning since someone was supposed to come Monday morning anyway to support the county inspection. Even though I called first thing Monday morning they couldn't guarantee the person that showed up could do anything. Sure enough, the guy the showed up wasn't even an electrician (not sure what he was supposed to do if the inspector found something he didn't like). As soon as I found that out I called Tesla and was on hold for about an hour (I was multitasking). I decided to do the callback option and got a callback early in the afternoon. They told me they needed to connect me to a different department and was put on a long hold again. I decided to leave a message (that line didn't have a callback option). I was transferred to a mailbox that was full with no way to get back to where I was in line so I had to start over. I finally got through late in the afternoon.
The person said I needed to sign a service agreement since the job had been "completed". I objected since my inspection hadn't been signed off, I don't have PTO, and my AC really wasn't working correctly from day one but they said that was the only way. I agreed and they said the form would show up under my account for me to digitally sign. There wasn't anything there Tuesday so I called Tesla again. They couldn't get the form to show up under my account so they said they would send me an Adobe Sign document. They said that would take a special person to send it to me. I finally got the document Wednesday morning and promptly signed it. I called them after that to make sure they got it (they didn't - I had to sign it again even though I got an email acknowledging I approved the first one) and to find out what happens next. They said it will take 24 hours for the "department" to review the form and approve it (it's their one page form - all I did was sign it in one place) and then they can get me transferred to scheduling. I called scheduling on Thursday. They said they didn't have the form yet so they couldn't schedule me. I called again on Friday and they said they still didn't have the form. After a while they determined they did have the form but couldn't see it in their system. I finally got an acknowledgement Friday evening that they could see the form and would work on getting me on the schedule. I got an email notice Monday morning that they would send a tech out the following Monday morning. This was the tech that wasn't a HVAC specialist and left with the AC completely inoperable.

By contrast, I twice had minor issues with my solar installation. I called my independent contractor and he took care of it the same day each time. Once he had to come over, and once he was able to talk me through a re-boot. A couple of times early on when I just had questions he got back to me in a reasonable time.

When I had the Roadster, Testa service was absolutely stellar. Based on what I read here on TMC, their service has declined terribly, depending on where you are. Clearly, they need far more service personnel.
 
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What they need is competent customer service and better after sale support. Transparency also goes a long way which is severely lacking across the board for PV installers, now throw in the PW and its just a money grab rather than proper training and educating their sales staff and engineers how to properly sell and size a system based on a candid QA with the customer ahead of time.
 
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What they need is competent customer service and better after sale support. Transparency also goes a long way which is severely lacking across the board for PV installers, now throw in the PW and its just a money grab rather than proper training and educating their sales staff and engineers how to properly sell and size a system based on a candid QA with the customer ahead of time.
When you get what you’re asking for, let me know. It seems easy, but you’d be surprised.
 
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I'm in a waiting pattern for the Gateway 2 to arrive (end of july) at the same time I'm pushing for them to install a 3rd PW on their dime b/c of my contract and all the correspondence. The PV system I did all my research and I'm happy with it, no complaints, but I also told them what I wanted and picked my own equipment and sized it myself. The PW debacle and dealing with Tesla is another story.

Hopefully you get your issue resolved as well.
 
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It looks like the Copeland SecureStart is a rebranded HyperEngineering SureStart. On the product's website, it shows a list of compatible compressors. Is there any reason the SecureStart with a compatible compressor wouldn't be able to handle being backed up by Powerwalls?
SecureStart™ for Copeland Compressors | Emerson US

Compatibility alone is just one issue, you need to have an understanding of the aggregate load during the times you want or expect the AC to run in backup mode. PW put out about ~30A realistically 28.5A, the sure start also varies, if you base the reduction on the maximum value they advertise you will be in for trouble. This all comes with experience and testing on different compressors and I don't think most of these companies have done their own due diligence so they make a lot of assumptions and put a bad taste in customers mouth when it does not work.
 
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