Welcome to Tesla Motors Club
Discuss Tesla's Model S, Model 3, Model X, Model Y, Cybertruck, Roadster and More.
Register

Hyper Engineering Sure Start in my 3 Ton A/C unit?

This site may earn commission on affiliate links.
On one of my Trane units, my A/C contractor was doing some service work and noticed this installed.

He says it was not installed by Trane so he had no idea how this part got installed.

Did Tesla install this in the unit at Solar and Power Wall installation????????

If they did how come in only one of units, not on the 4 ton.

I made a fuss with the contractor telling him no one has touched the unit but them.

I think I am wrong.

Why did Tesla Install this. It is an expensive hard start kit.


Comments?
 

Attachments

  • IMG_6453 copy.png
    IMG_6453 copy.png
    714.7 KB · Views: 389
Tesla installed one in mine, but I saw them do it and it was part of the procedure when the PWs were installed.

They only had one unit, and I only have one compressor, so maybe they didn't have a second one for you.

Also they only need to be installed on units with a high LRA. It is possible your 4 ton unit doesn't require it.
 
On one of my Trane units, my A/C contractor was doing some service work and noticed this installed.

He says it was not installed by Trane so he had no idea how this part got installed.

Did Tesla install this in the unit at Solar and Power Wall installation????????

If they did how come in only one of units, not on the 4 ton.

I made a fuss with the contractor telling him no one has touched the unit but them.

I think I am wrong.

Why did Tesla Install this. It is an expensive hard start kit.


Comments?

Tesla most likely installed it during your powerwall install, to enable you to actually start your AC up when you are off grid. Start up loads for AC units can be much higher than what is needed to keep them going.

on a complete side note, perhaps this is just me, but when I see a question framed with ???????????????????????????????????????????????????????????

After it, I usually feel less inclined to respond. Using a lot of punctuation, to me at least, may not convey the meaning that the poster is going for (or maybe it does, I dont know???????????????????????

In any case it was almost assuredly installed by tesla during your powerwall install, to enable the unit to work when off grid, and as stated by @power.saver either your other unit doesnt need it, or your other unit isnt backed up (available when off grid).
 
  • Like
Reactions: BGbreeder
Lol I agree with jjrandorin... more ???????? is inversely proportional to how many fuchs people give.

But to answer your question, the device you took a picture of is called a "Soft Start". They are often called "Secure Start" or "Sure Start" by various manufacturers who want to trademark the term for their sales team and confuse the ever living hell out of customers.

Anyway, the reason you may need one of these is that a traditional scroll compressor takes a large inrush of current to start up the compressor. This is called "LRA" or locked rotor amps. You can look at the nameplate of your Bryant or Trane or whatever hell condenser you have and it'll tell you LRA.

The problem people have when they go off grid (when the PoCo power is unavailable) is that Powerwalls may struggle to release the burst of energy required to overcome the LRA of most common air conditioning units. Basically, the AC needs a bunch of amps and one or 2 Powerwalls can't output enough to start the compressor for those precious few milliseconds it takes to get the compressor to turn over.

This same problem happens with people who own RVs who have air conditioners that struggle to start because they take more juice than the on-board alternator and/or batteries can provide.

The "Soft Start" is a bit of kit that learns the exact LRA curve the specific compressor needs. It is able to effectively regulate the juice your compressor needs so when it starts, it reduces the LRA.

Based on numerous TMC posts, Tesla installers often install a soft start on a customer's backed-up AC unit to make sure the thing starts when the power company goes offline. As jjrandorin said... maybe your 4 ton unit is not backed up while your 3 ton unit is. And therefore the backed up unit gets the soft start.

What is super duper annoying is Soft Starts are not normal HVAC equipment. Most HVAC pros know what is a "hard start". This is a capacitor kit that is meant to help an old compressor get enough juice to turn over. But hard starts actually INCREASE LRA. The problem is if you ask a HVAC pro to help a situation involving starting a compressor, their training automatically wires their brain to think "oh man this is what a hard start is for!" Then you get boned because HVAC people don't install Tesla Powerwalls.

But what does all this mean to you?????????????????? Absolutely nothing of value.

Because your system is working fine with the Hyper Sure Start when the power company is online. It means the power company can go dark, and your backed up AC should turn on just fine as well with only your Powerwall(s). Go test it if you have time.

You should also confirm what's up with your 4 ton unit. It sounds like it's NOT backed up. If you think otherwise, it seems Tesla forgot to install a soft start on there. Or maybe your 4 ton is a variable speed inverter-driven compressor and doesn't have trouble starting up.

Edit: be glad that they actually installed the Soft Start. One TMC user had the installer just put the soft start in a baggie and throw it into the condenser unit. Too funny. A soft start needs to learn the LRA curve to be useful. You cannot install a soft start after the AC unit is already stalled out and hope to get benefit from the soft start.
 
As mentioned, SureStart is a soft start device installed by Tesla. However, they are not compatible with all AC units. In my case I have a compressor that runs in one direction during low stage operation and the other direction during high stage operation. SureStart is not compatible with this type of operation and caused all sorts of problems.
Tesla and I are at a standoff at this point. They claim that they do not guarantee the AC will work in a whole house backup. My position is a whole house backup should include AC. My frustration is there are other less complicated soft start devices that work with reverse run motors but Tesla refuses to install anything other than Hyper-Engineering Sure start devices. The SureStart is a smart device that learns the start profile but the problem is it doesn't understand the reverse run operation. The more industrial soft start devices that work with reverse run motors require manual setting of the start profile.
 
As mentioned, SureStart is a soft start device installed by Tesla. However, they are not compatible with all AC units. In my case I have a compressor that runs in one direction during low stage operation and the other direction during high stage operation. SureStart is not compatible with this type of operation and caused all sorts of problems.
Tesla and I are at a standoff at this point. They claim that they do not guarantee the AC will work in a whole house backup. My position is a whole house backup should include AC. My frustration is there are other less complicated soft start devices that work with reverse run motors but Tesla refuses to install anything other than Hyper-Engineering Sure start devices. The SureStart is a smart device that learns the start profile but the problem is it doesn't understand the reverse run operation. The more industrial soft start devices that work with reverse run motors require manual setting of the start profile.


Just a random recommendation from a random person online... but your situation seems rather straightforward to resolve with a small claim. If you feel there is...

1) clear documentation as provided by Tesla that you both agreed to stating your air conditioner would be "backed up"
2) some quote/documentation you have from a licensed/authorized personnel to work on your air conditioners stating that the air conditioner does not work due to modifications made by tesla
3) some proposal (hopefully with an estimated total cost less than the small claims limit of $10,000) from a licensed/authorized personnel to execute a repair for your air conditioner to get it to function properly
4) any other damages like out of pocket diagnostic costs or the inability to cool your home that you incurred due to your AC not working after Tesla messed with it.
Edit 5) documentation that shows you attempted to remedy this by working with Tesla, and ideally that they acknowledge there could be some issue. But that Tesla did not deliver a resolution.

It's a few hundred bucks to file, and you are not on the hook for opposing legal fees even if the judgement is not in your favor. However, I feel if you had the above 5 things lined up you should consider this option. The offer to do a "whole home backup" (either expressly stated or inferred) to include your AC likely came from Tesla's own design team... which in my opinion makes this an even stronger case for you. I don't think small claims can compel Tesla to perform a fix. Instead a successful claim will provide cash to the extent you could pay whoever in step #3 to complete the repair for you.

I think Tesla could make an argument that the AC is not part of the "whole house" since the condenser sits outside of your house. Or maybe they buried some asterisk someplace that says they're not actually responsible if they fail to do what they said they would do. But I can't imagine a reasonable person making that inference or allowing that type of disclaimer.
 
Last edited:
I think Tesla could make an argument that the AC is not part of the "whole house" since the condenser sits outside of your house. Or maybe they buried some asterisk someplace that says they're not actually responsible if they fail to do what they said they would do. But I can't imagine a reasonable person making that inference or allowing that type of disclaimer.
I don't think it being outside of the home would likely be an issue - and I expect "whole house" is really just marketing puffery anyway. The more important question is whether Tesla knowingly wired the compressor into the backup panel. If so, then they were essentially saying it is part of the backed up circuits. Of course, they do have exclusions for non-compliant units, which makes sense as a customer could change units later, and Tesla is not responsible for a new unit not working (potentially unless Tesla maintains an "approved" list or compliance specs that the new unit meets.)

So it really gets down to your points above, which I agree with, where it would likely be about the details of whether Tesla represented that they would support the unit in question as part of the agreement but then failed to actually support it.

I would also note that with Tesla, arbitration may be an option as well, which is no cost to the customer. I do not know which path might be a better option.
 
Just a random recommendation from a random person online... but your situation seems rather straightforward to resolve with a small claim. If you feel there is...

1) clear documentation as provided by Tesla that you both agreed to stating your air conditioner would be "backed up"
2) some quote/documentation you have from a licensed/authorized personnel to work on your air conditioners stating that the air conditioner does not work due to modifications made by tesla
3) some proposal (hopefully with an estimated total cost less than the small claims limit of $10,000) from a licensed/authorized personnel to execute a repair for your air conditioner to get it to function properly
4) any other damages like out of pocket diagnostic costs or the inability to cool your home that you incurred due to your AC not working after Tesla messed with it.

It's a few hundred bucks to file, and you are not on the hook for opposing legal fees even if the judgement is not in your favor. However, I feel if you had the above 4 things lined up. The offer to do a backup that included your AC likely came from Tesla's own design team... which in my opinion makes this an even stronger case for you. I don't think small claims can compel Tesla to perform a fix. Instead the claim will provide cash to the extent you could pay whoever in step #3 to complete the repair for you.

I think Tesla could make an argument that the AC is not part of the "whole house" since the condenser sits outside of your house. But I can't imagine a reasonable person making that inference.
It's a little more complicated than that.

1) If you look at the contract there is nothing that explicitly states what devices will be backed up in a whole home backup configuration. Their position is that since it isn't explicitly stated that the AC will be backed up it isn't guaranteed. In fact, they don't even use the term whole home backup in their contract. You have to rely on the schematic that you approved prior to installation to show the intent was to have everything backed up.

2) When the SureStart was first installed the AC (actually a hybrid heat pump/gas furnace system) the system would sometimes start, sometimes not start. And when it stopped it made this big bang. It has a computerized control system that is connected to the internet. I had nearly 100 email messages that there were problems with my system and error messages would show on the thermostat display. Tesla sent another tech out to correct the problem. He couldn't get the AC to work correctly and removed the SureStart device. However, the AC would no longer function after the device was removed. The tech said there must be something wrong with my system and need to call a HVAC repair service. And then he left. I pulled of the panel on the outside unit and saw that the tech hadn't rewired the unit correctly per the schematic on the inside panel. I rewired the unit per the schematic to get the HVAC working again.

3) I can't find any HVAC contractors that will install a soft start device. And honestly, it is probably beyond their capability. They just want to replace my system with a variable speed system so they can make some money.

4) This has been going on since June of 2020 when the Powerwalls were installed. I was the one that contacted Hyper-Engineering and found out the SureStart device wasn't compatible with my compressor. I can currently get my AC to work during a power outage by locking out high stage and timing the compressor start to coincide with the window when my solar is producing. However, if the AC tries to start after the Gateway has commanded the solar off or if the compressor is running when the power goes down, the Powerwalls will trip for a few seconds and then restart. The problem with this is if I'm not home the system will get into an endless cycle of restarts until the the temperature is low enough that the HVAC no longer calls for cooling.

Tesla has given me 2 options:

1) Have them install a 3rd Powerwall 2 (what they call Series 3 Powerwall 2's). The newer Powerwall 2's have a greater surge capacity and this will provide more than enough current to start my compressor. They want me to pay for this but will give me a discounted price of $5K which I agree is a good price but I feel I shouldn't have to pay additional money for something that is their responsibility. And in my situation the 3rd Powerwall won't have much benefit other than starting my HVAC compressor. I suggested they replace my current older Powerwall 2's with the Series 3 units (I would accept refurbished units) which would provide sufficient surge capacity but they won't do that.

2) Use load shedding to lock out my HVAC system during a power outage. Initially I told them I would be open to this if they put a switch in to allow me to manually override the lock out so I can continue to use the AC when the solar is producing. But they won't do that. And they said doing nothing isn't an option. They will void my Powerwall warranty if I don't do either of the options. So I told them I would proceed with load shedding but I wanted some assurances since I believe they don't comprehend the complexity of my system.
They keep talking about splicing into my thermostat wires at the outside unit to do the load shedding. To begin with, my thermostat wires do not go to the outside unit. I have a communicating system with smart thermostats that use Data A, Data B, 24V, and common wires. My main thermostat uses these signals to communicate with the control board on the air handler. The air handler then communicates with the outside unit through a separate set of wires that go to a control board on the outside unit. So I'm concerned that any splicing into this system will cause system errors. The most frustrating part about this is my system has a utility curtailment feature with terminals on the outside unit SPECIFICALLY for load shedding but Tesla refuses to use these.
I told them I wouldn't agree to proceed with load shedding unless:
a) They will confirm to their satisfaction that my system is working properly before they begin work and they don't leave unless my system is working properly after they do their work.
b) As I mentioned I have a hybrid system that can either run in heat pump mode or gas furnace mode. The gas furnace can run during a power outage with a minimal power requirement. This is how I heated my house using a generator during a power outage before I got the Powerwalls. I want Tesla to confirm that I will still be able to use the gas furnace during a power outage if they incorporate load shedding.

I'm still waiting for Tesla's response.
 
@RKCRLR, your situation is like wacky as hell. But I think there is enough to get a resolution.

Do you have...
a) some evidence to support a claim that someone involved with the research/design Team either personally inspected or otherwise obtained your AC brand/nameplate data?
b) In the schematic (presumably the one that has the Tesla logo on it)... that clearly shows the AC circuit is on the "backup loads" side?
c) the confidence that nobody at Tesla informed you during the design/planning phase that your AC unit may not be compatible with the proposed design?

I think it is possible to literally delete the entirety of the attempt to resolve with Tesla and initially say your claim is to get a new condenser with a variable speed compressor per a 3rd party quote. Presumably, the 3rd party installer is willing to support a statement that the new condenser will remedy the situation of your AC not starting properly.

I think you should leave it up to Tesla to say another solution is a $5,000 Powerwall; and let the dispute resolution gravitate to Tesla's "option" if Tesla could make a case that their solution is better. I think you've demonstrated that you've attempted to resolve this in good faith, so you might as well go with what you know. And we know a reputable variable speed compressor doesn't have a high LRA.


@wjgjr , I personally feel small claims is better simply because lawyers are typically not allowed in small claims dispute resolution. My opinion here is that RKCRLR should have documentation literally provided by Tesla showing their intent was to back up the AC. And similarly, Tesla designers/installers (who presumably know their own AC exclusion criteria) seemed to have failed to alert RKCRLR in a reasonable way that his AC unit may not work.

I wonder, if Tesla ever sent an email to RKCRLR like "we'll try to get your AC to work, but it's a weird dual stage monster... who the heck knows!".

To your point about puffery... when I did my 3 Powerwall "whole home" backup through Sunrun, I learned "whole home" didn't actually mean the AC's. Sunrun's designers told their sales guy... ACs should never be backed up. If the customer wants AC on the backup side, then the salesman needed to clearly confirm that the customer understood the risks. But based on RKCRLR's posting here, I get the feeling at no point in time during the installation did he feel AC's were out of scope.

Edit, I don't know what the Tesla contract looks like, but it's possible RKCRLR waived his right to pursue small claims as a resolution path. So I guess he could be stuck with the process that lets Tesla lawyer RKCRLR to death. Sad.
 
@RKCRLR,

Do you have...
a) some evidence to support a claim that someone involved with the research/design Team either personally inspected or otherwise obtained your AC brand/nameplate data?
b) In the schematic (presumably the one that has the Tesla logo on it)... that clearly shows the AC circuit is on the "backup loads" side?
c) the confidence that nobody at Tesla informed you during the design/planning phase that your AC unit may not be compatible with the proposed design?

I think it is possible to literally delete the entirety of the attempt to resolve with Tesla and initially say your claim is to get a new condenser with a variable speed compressor per a 3rd party quote. Presumably, the 3rd party installer is willing to support a statement that the new condenser will remedy the situation of your AC not starting properly.

I think you should leave it up to Tesla to say another solution is a $5,000 Powerwall; and let the dispute resolution gravitate to Tesla's "option" if Tesla could make a case that their solution is better. I think you've demonstrated that you've attempted to resolve this in good faith, so you might as well go with what you know. And we know a reputable variable speed compressor doesn't have a high LRA.


@wjgjr , I personally feel small claims is better simply because lawyers are typically not allowed in small claims dispute resolution. My opinion here is that RKCRLR should have documentation literally provided by Tesla showing their intent was to back up the AC. And similarly, Tesla designers/installers (who presumably know their own AC exclusion criteria) seemed to have failed to alert RKCRLR in a reasonable way that his AC unit may not work.

I wonder, if Tesla ever sent an email to RKCRLR like "we'll try to get your AC to work, but it's a weird dual stage monster... who the heck knows!".

To your point about puffery... when I did my 3 Powerwall "whole home" backup through Sunrun, I learned "whole home" didn't actually mean the AC's. Sunrun's designers told their sales guy... ACs should never be backed up. If the customer wants AC on the backup side, then the salesman needed to clearly confirm that the customer understood the risks. But based on RKCRLR's posting here, I get the feeling at no point in time during the installation did he feel AC's were out of scope.

Edit, I don't know what the Tesla contract looks like, but it's possible RKCRLR waived his right to pursue small claims as a resolution path. So I guess he could be stuck with the process that lets Tesla lawyer RKCRLR to death. Sad.
a) Yes, in fact Tesla initially said I didn't have a reverse run compressor and sent the photo of the nameplate that I provided prior to the install. I sent them a data sheet for my outside unit showing it was a specific compressor that was reverse run. They then admitted they pulled the wrong version of the data sheet.

b) Yes.

c) I initially had concerns about the setup for different reason and tried to communicate with Tesla. However, technical communication isn't in Tesla's wheelhouse. If they would let me talk to someone technical we could probably come to a resolution. But Tesla never voiced any concerns about the AC not working. And, after talking with Hyper-Engineering, they probably weren't aware of a problem. Hyper-Engineering said they have never seen a reverse run compressor and that it must be something new. However, my unit was installed in 2008. And I don't think revers run AC compressors are even used anymore.

There is an arbitration clause in the contract so that would be the first step. The problem with paying for a fix myself and then sending a bill is that I could lose. Been there, done that.
 
a) Yes, in fact Tesla initially said I didn't have a reverse run compressor and sent the photo of the nameplate that I provided prior to the install. I sent them a data sheet for my outside unit showing it was a specific compressor that was reverse run. They then admitted they pulled the wrong version of the data sheet.

b) Yes.

c) I initially had concerns about the setup for different reason and tried to communicate with Tesla. However, technical communication isn't in Tesla's wheelhouse. If they would let me talk to someone technical we could probably come to a resolution. But Tesla never voiced any concerns about the AC not working. And, after talking with Hyper-Engineering, they probably weren't aware of a problem. Hyper-Engineering said they have never seen a reverse run compressor and that it must be something new. However, my unit was installed in 2008. And I don't think revers run AC compressors are even used anymore.

There is an arbitration clause in the contract so that would be the first step. The problem with paying for a fix myself and then sending a bill is that I could lose. Been there, done that.


You may want to reach out to the SEIA first. Tesla Energy is a SEIA member and has placed a member of Tesla Energy on the SEIA board. There should be resources that the SEIA may be able to provide resources to you with regard to your situation with Tesla Energy. Worth a consideration.

If you don't make progress with the SEIA, I don't think you need to come out of pocket first then then arbitrate. I think having a bid from a reputable contractor with a proposed solution is enough to quantify the amount of your claim. But that's just me...

1633543483827.png


[email protected]
 
I don't think it being outside of the home would likely be an issue - and I expect "whole house" is really just marketing puffery anyway. The more important question is whether Tesla knowingly wired the compressor into the backup panel. If so, then they were essentially saying it is part of the backed up circuits. Of course, they do have exclusions for non-compliant units, which makes sense as a customer could change units later, and Tesla is not responsible for a new unit not working (potentially unless Tesla maintains an "approved" list or compliance specs that the new unit meets.)

So it really gets down to your points above, which I agree with, where it would likely be about the details of whether Tesla represented that they would support the unit in question as part of the agreement but then failed to actually support it.

I would also note that with Tesla, arbitration may be an option as well, which is no cost to the customer. I do not know which path might be a better option.
The only breaker in my backup panel is the 200 amp breaker for my house. Between the schematic and the attempted installation of the SureStart if is obvious that the intent was to have the AC backed up. But I can't fault Tesla for not knowing that my AC compressor wasn't compatible with the SureStart. Hyper-Engineering wasn't even aware of reverse run compressors in HVAC units until I talked to them. That is when they investigated my problem and told me the SureStart wasn't compatible with reverse run compressors.

The question here is who is financially responsible to correct the problem in a situation like this.
 
@wjgjr , I personally feel small claims is better simply because lawyers are typically not allowed in small claims dispute resolution. My opinion here is that RKCRLR should have documentation literally provided by Tesla showing their intent was to back up the AC. And similarly, Tesla designers/installers (who presumably know their own AC exclusion criteria) seemed to have failed to alert RKCRLR in a reasonable way that his AC unit may not work.

I wonder, if Tesla ever sent an email to RKCRLR like "we'll try to get your AC to work, but it's a weird dual stage monster... who the heck knows!".

To your point about puffery... when I did my 3 Powerwall "whole home" backup through Sunrun, I learned "whole home" didn't actually mean the AC's. Sunrun's designers told their sales guy... ACs should never be backed up. If the customer wants AC on the backup side, then the salesman needed to clearly confirm that the customer understood the risks. But based on RKCRLR's posting here, I get the feeling at no point in time during the installation did he feel AC's were out of scope.

Edit, I don't know what the Tesla contract looks like, but it's possible RKCRLR waived his right to pursue small claims as a resolution path. So I guess he could be stuck with the process that lets Tesla lawyer RKCRLR to death. Sad.
Regarding small claims vs arbitration, at least my contract with Tesla provided within the arbitration clause that I also had the option to file in small claims court. Not sure if that is in the current contract, but both might be options. Not disagreeing that small claims might be best - just that both options exist.

Regarding "whole home", I think that illustrates the point about it just being a marketing term - "whole home" is just a way to promote their backup solution. It does not convey any legal commitments as far as what, specifically, will be included/excluded. That should be documented in the agreement.
 
You may want to reach out to the SEIA first. Tesla Energy is a SEIA member and has placed a member of Tesla Energy on the SEIA board. There should be resources that the SEIA may be able to provide resources to you with regard to your situation with Tesla Energy. Worth a consideration.

If you don't make progress with the SEIA, I don't think you need to come out of pocket first then then arbitrate. I think having a bid from a reputable contractor with a proposed solution is enough to quantify the amount of your claim. But that's just me...

View attachment 718441

[email protected]
My approach is to see how Tesla responds to my concerns. If they agree then I will probably let them do the load shedding and then put a switch in the wire after they leave so I can manually override it, assuming it works. And possibly connect the load shedding wires to the load shedding terminals on my system that are INTENDED TO BE FOR LOAD SHEDDING if they don't come to their senses.

If they disagree or their load shedding approach causes problems then I will probably take them to arbitration.
 
Regarding small claims vs arbitration, at least my contract with Tesla provided within the arbitration clause that I also had the option to file in small claims court. Not sure if that is in the current contract, but both might be options. Not disagreeing that small claims might be best - just that both options exist.

Regarding "whole home", I think that illustrates the point about it just being a marketing term - "whole home" is just a way to promote their backup solution. It does not convey any legal commitments as far as what, specifically, will be included/excluded. That should be documented in the agreement.


IMO, the installer is responsible for informing the customer of the limits of "whole home" at some point in time during the install. Sunrun introduced the problem by initially refusing to do a design that was a "whole home" backup that included the AC.

By producing a design diagram the way they did; I feel Tesla just reinforced the false inference that "whole home" includes the ACs. And since Tesla knew his model/type of AC, up front, I would hope a reasonable/neutral arbitrator would see Tesla would be responsible to deliver a "whole home" in a manner that a normal person would interpret "whole home."

But I agree about puffery... it's widely used in almost all advertising. It presents a really annoying grey area to be in with regard to an emerging technology of solar + batteries.
 
The only breaker in my backup panel is the 200 amp breaker for my house. Between the schematic and the attempted installation of the SureStart if is obvious that the intent was to have the AC backed up. But I can't fault Tesla for not knowing that my AC compressor wasn't compatible with the SureStart. Hyper-Engineering wasn't even aware of reverse run compressors in HVAC units until I talked to them. That is when they investigated my problem and told me the SureStart wasn't compatible with reverse run compressors.

The question here is who is financially responsible to correct the problem in a situation like this.
It seems to me the answer is Tesla, who could then take it up with Hyper-Engineering, depending on the agreements those companies have in place. In this situation Tesla is the expert, and it is their responsibility if they are committing to supporting the A/C to ensure that it is compatible. That is exactly what they did in our case (installed before yours.) If they failed - even if it is because they didn't know about the technology - it is still their responsibility since they knew what you had and accepted the work.
 
My approach is to see how Tesla responds to my concerns. If they agree then I will probably let them do the load shedding and then put a switch in the wire after they leave so I can manually override it, assuming it works. And possibly connect the load shedding wires to the load shedding terminals on my system that are INTENDED TO BE FOR LOAD SHEDDING if they don't come to their senses.

If they disagree or their load shedding approach causes problems then I will probably take them to arbitration.


IMO, I think this load shedding solution is DOA for your situation. Assuming you have an old two-stage unit, you have two separate 24v control wires to send a signal to the compressor to run at either stage 1 or 2. The TEG2 diagram shows only one 24v trigger wire circuit can be "opened" when the utility power is unavailable.

At this point, I think you should stick with solutions that work per the recommendation of an external HVAC expert. The more you try to find a funky/wonky fix the more this feels like it heads off the rails.
 
IMO, the installer is responsible for informing the customer of the limits of "whole home" at some point in time during the install. Sunrun introduced the problem by initially refusing to do a design that was a "whole home" backup that included the AC.

By producing a design diagram the way they did; I feel Tesla just reinforced the false inference that "whole home" includes the ACs. And since Tesla knew his model/type of AC, up front, I would hope a reasonable/neutral arbitrator would see Tesla would be responsible to deliver a "whole home" in a manner that a normal person would interpret "whole home."

But I agree about puffery... it's widely used in almost all advertising. It presents a really annoying grey area to be in with regard to an emerging technology of solar + batteries.
I think we generally agree - my initial point was Tesla couldn't hide behind "whole home" - as you suggested Tesla might try - by excluding a compressor because it is technically outside the 4+ walls of the home since it means nothing. In the end, "whole home" is to me not particularly relevant to this discussion. The real question is whether, in the technical design and agreement, Tesla committed to including the A/C in the contracted backup solution. If so, then they have a responsibility to deliver that or pay appropriate damages.
 
IMO, I think this load shedding solution is DOA for your situation. Assuming you have an old two-stage unit, you have two separate 24v control wires to send a signal to the compressor to run at either stage 1 or 2. The TEG2 diagram shows only one 24v trigger wire circuit can be "opened" when the utility power is unavailable.

At this point, I think you should stick with solutions that work per the recommendation of an external HVAC expert. The more you try to find a funky/wonky fix the more this feels like it heads off the rails.
There is no way a variable speed 5 ton AC unit would be less than the $5K that Tesla is proposing for a 3rd Powerwall, which would address the problem. So I'm not sure that getting an estimate for that would be of much benefit. It likely would require replacement of my air handler also. And I have a zoned system with 3 zones. It would probably be close to $20K if the whole system had to be upgraded.

There aren't 2 separate 24v wires going to my outside unit. There is Data A, Data B, 24V, and common that come from the air handler and communicate with the control board on the outside unit. The outside unit control board then activates the appropriate relays to run the compressor at the right settings.

However, the main thermostat has settings for the utility curtailment feature. I can lockout the high or both stages on both the AC and heat pump. I could set the default for heat pump and AC disabled and then manually switch to low stage AC only if I want to run the AC during a power outage. When the utility curtailment feature is enabled the system will invoke the curtailment settings when the utility curtailment terminals on the outside unit go open. My understanding is the TEG load shedding terminals go open during a power outage. But Tesla is insisting on splicing into the thermostat wires instead of using the utility curtailment terminals.
 
Sometimes I think you’re working against yourself. Like in one hand you’ll say you’re harmed then in the other you make the situation seem like a possible misunderstanding.

Don’t outsmart the system. Stick with facts and things you know.

You entered into agreement for a product that contractually promised to give you solar and a whole home backup.

You allowed Tesla full access to whatever they needed to understand your home.

You received from Tesla a design proposal that was a whole home backup to your understanding.

You attempted to discus your air conditioner with Tesla during the process, lending support to a claim that AC was of importance to you.

Tesla delivered their diagramed solution as they drew up.

The diagramed solution does not backup an important part of your home.

You can either say your damage is either …

1) the diminished value of your system since it’s not working as it should and never will within reason.

2) the cost / repair to make it work as it should in a way that seems realistic and possible. Focus on ideas that will work instead of ideas that may work.

Lay out these points clearly and go find someone who can help you. Arbitration, the SEIA, California consumer protection groups, small claims, etc. good luck!
 
Last edited: