Yeah, the problem with these industries (solar and HVAC) is that the pros who do it for a living seem to have a feeling that their specialized knowledge is also common knowledge when the situation suits them.
For example, if you ask an HVAC person about soft starts, they're going to tell you how stupid you are for buying normal single or dual stage scroll compressors. Because if it were their money, they'd get a variable speed inverter driven compressor because those are newer/better. They don't like hard starts and soft starts because these are hacks and kind of violate their school of training and experience. So they'll blame you for being stupid and not having a variable speed compressor if you also wanted to have fancy batteries or generators running your home.
And then if you ask solar people about soft starts, they'll say they're not HVAC experts and how they wouldn't be expected to know how your specific HVAC works. So it's your fault for not selecting the right HVAC for a whole home backup solution and informing them of your unique situation with an odd-style outdoor condensing unit.
In the end you have two industry expert groups both blaming the ignorant homeowner for failing to have the foresight to understand how stuff works. It sucks for the average homeowner... who wouldn't reasonably have this type of knowledge unless they were just born with huge amounts of innate knowledge (wwhitney? heh).
In your case you're kind of SOL unless you agree to either move the AC to a non-backup loads panel. Or you upgrade your antiquated outdoor condensing unit with a system that has a lower LRA.
Overhauling an HVAC to get a variable speed outdoor condenser paired with a variable speed air handler and with a new variable speed capable communicating thermostat is expensive though. But in this case I cannot see Tesla stepping up to do anything for you because they have no other options on the energy side. Maybe if Tesla ever started to make heat pumps and HVAC things would be a bit different where they could help you get a new HVAC system for cheaper...
PS. I screwed up and didn't get variable speed condensing units on my house. I am an idiot as I've been made aware numerous times by HVAC people. If anyone reading this ever is in the market for an HVAC replacement... I recommend you only look at variable speed units or go with mini splits.
I'll give a little more background.
First, there are soft start devices available other than SureStart. Soft start devices are common in industrial applications. The problem with the SureStart is it is a learning soft start device and the microprocessor gets confused by the reverse run operation. There are dumb soft start devices available that require manual setup. However, Tesla's policy is they only install SureStart devices.
My Carrier Infinity hybrid (propane and electric) heat pump system is a microprocessor controlled communicating system. When Tesla initially installed the SurStart, the system was throwing all sorts of error codes and would make a big bang when it shut down. When the third tech came out to fix it and couldn't, I told him to just remove the SureStart. When he removed the SureStart my system would no longer work. The tech told me there must be something wrong with my system and to call a HVAC repair place, and then he left to get to another appointment. When I compared the wiring to the schematic on the inside panel I found he had rewired the unit incorrectly. I rewired the unit correctly myself to get the unit operating again.
Tesla was doing nothing to resolve this. I was the one that contacted HyperEngineering, sent them the appropriate information, and they then said SureStart wasn't compatible with my system. They said this is the first time they had encountered this and it must be a very new application (the unit is actually 10 years old).
This got escalated to Tesla Executive Resolutions. I'm not allowed to communicate with the technical people directly. I've got numerous emails and phone calls back and forth with them not answering my questions and, but the responses I get, don't understand my system. They want to use the load shedding terminals on the Gateway and splice into my thermostat wires. However, my thermostat isn't a normal 2 wire connection. It has 4 wires (Data A, Data B, Common, and 24V) and is wired to my inside unit control board which then communicates with the control board outside unit to command how it operates. The frustrating thing about this is my system has a utility saver mode that when connected (simple open/closed command) will prevent the AC from running when commanded. It can also to be set to low stage only which would allow the unit to start off the Powerwalls during a power outage. However, it is not Tesla's policy to use this. Because of my previous experience I don't have confidence they understand my system and refused to proceed until they show me a detailed plan on how they intend to do the wiring. So far, they have refused to do this. I want to make sure my system doesn't throw a bunch of errors, inside unit doesn't continue to run when there is a power outage (it was running full blast during previous problems), my propane furnace will continue to operate during a power outage, etc.
They've stretched this out so long now there are other options available with the Powerwall 2 upgrade. The newer Powerwall 2s support 106 LRA each (I have 2). This would be more than enough to start my compressor during an outage. It may even be possible that a firmware upgrade could address this. But, again, communication with Tesla is frustrating.
At this point I'm so frustrated that I'm digging my heels in. They agreed to a whole home backup with AC and that is what I want. If their internal policies prevent using other soft start devices or my utility curtailment feature then fine. Replace my 2 Powerewall 2s with upgraded units that will do the job.
