So the lower floor AC unit has been non-operating for six years? What exactly is happening?

Is your step-dad merely unable to handle the situation, or is he also unwilling to let others handle the situation?

What does the HVAC service company say exactly is the reason the unit won’t start back up or whatever is going on? Do they have a proposal to fix it? I’d start there.

You can make calls and figure that out, even schedule the HVAC company to come out and look at the unit, from your location. Assuming step-dad is not obstructionist.

I'd contact another hvac contractor and have them come out for a service call. After that, post all the findings here for review. Your previous checks don't say anything about what the two groups each found performing correctly and what was not. We need info on the system.

Info- The DIY HVAC Guy - YouTube

Your "long story" left out many facts and by the time they pass from stepdad to you then from you to us I seriously doubt they can be established. ANY COMPITENT hvac tech should be able to answer your questions. The most important fact is whether elect company controls power to equipment or do they control equipment control system. That makes a huge difference in how to go about resolving problem.

Thank you all for your comments. And I certainly realize that there are huge holes in my story. I guess I'm looking for two things: first, the unicorn, "this exact same thing happened to me and here's what happened...." and the more likely choices "here are some things that it might be" or "here are some questions to ask"

Klem1....your question about where the power company's control is actually a pretty helpful start.

I will definitely be making phone calls on Monday. In the meantime, if anyone has suggestions on some questions to ask, please feel free. I am usually a reasonably competent person, but as noted, filtering through the original service professionals, through my step dad, over time makes me less sure of my ability to deal with this.

My step-dad is not really an obstruction, but it is a challenge. When I suggest a possible solution to the problem, he will say that it won't help, but is unable to express why it won't or clearly express/remember what has already been said and tried.

Based on this brief conversation I honestly believe you are either incapable of handling it or you are not being candid. You want us to give you questions to ask but you evade our questions.

Kleenex, oh, excuse me, autocorrect....klem, pray tell, what questions am I evading? I am passing along all the information I have from a wonderful person I love who is going into serious cognitive decline.

I have not started my phone calls, so I really don't know what HVac said besides "it's the electric company". I don't know what the electrician said besides "it's the electric company", and I don't know what the electric company said besides "it's not us". I may certainly have jumped the gun on coming here for advice before I had more information. However, this is a situation that has never been in my hands before.

I've been a homeowner for 25 years and this isn't the first system challenge I've had, but it certainly is the most complicated. Add in the emotional and distance components, and I do appreciate any help I can get in handling this expeditiously.

Charles Ross Homes, I certainly admit that may be the end result. I will need to find out more about DTE'S program to ensure that will solve the problem. If their control is at the panel, I imagine it might complicate matters.

You can start here.

https://www.dteenergy.com/us/en/residential/save-money-energy/get-started-with/demand-response.html

Thank you mad_gallica. That was going to be a starting point after I get the kids to bed. You've saved me a little searching.  

I think the question to ask is: ”Dear HVAC company, when can you come out to fix our AC?”

I wouldn’t waste time trying to find whoever looked at it six years ago and asking them to rehash whatever the debate was back then. If they even remember, or are even still at the company.

If you’re serious about getting this fixed and your stepdad is as befuddled as you say, you need to make the drive and be there when the HVAC company is, to give them instructions so that he doesn’t.

The next question, of course, will be ”how much will it cost”.

Probably a fair bit more than it would have cost six years ago . . . but it has to be done.

Also, maybe withdraw your folks from the program (that lets the power company shut things off).

Is there some reason your parents can't cancel participation in that demand-control program with the electric provider? They probably receive a small monthly bill credit for participating but seems it's not worth the years of unresolved headache.

The electric cooperative here has a similar (voluntary) program for air conditioning and electric water heaters. They can shed (deactivate) them if necessary during times of peak power demand, on rotating cycles (participating customers are not all shut off the same time) of 7.5 mins off twice per hour, typically between 3 and 8 PM ... but only during the months of June, July, and August. A $25 bill credit is applied during those months for each enrolled device in a household. A device is wired-in at each unit, controlled by a signal sent over the power line.

I don't participate in the program so I can't say how the air conditioning control interfaces to the system ... if it interrupts the 240v power supply to the unit or if it interrupts the low-voltage thermostat control. Many air conditioners have a 5-minute delay before the compressor starts after a both a thermostat shut-off or a power outage so a 7.5 min shut-off would entail an additional 5 mins wait.

I'm not auguring dadoes, just offering advice folks on this program need to know. Delays are available for delay on break or delay on make. On break version time begins when power fails so it's over before utility restores power. 90% my career involved property which I had financial interest so if not factory installed I always added one.

HVAC pro is primarily for electrical problems with the unit in question. Typically power company control for bill credit is primarily (old days) a box that it attached on the outside condenser to control control voltage to the unit. There were visual indicactors on the one's I worked on back when HP&L was the only game in town, before de-regulation. During that time we were told as techs not to disconnect them... (it's fairly simple, any tech with common sense could disconnect them and restore the unit to turn on again.)

After deregulation here there was a pretty good stream of calls to disconnect these boxes, remove them etc. (This story is a part of the great Houston metropolitan area -- I service the west side about 3 clicks west of this gates of hell area.)

If you are in some sort of program, pay the tech to disable it (IF that is what the problem is - I say this because we don't fix things remotely in the HVAC industry) If you are under contract with some provider and you disable it, you may get fined, or ?? read your contract.

If you're no longer under that contract? pay the tech to disable it. Tell them in advance before they come... if they say they can't do it have them explain why. (They may say it is up to your electrical provider to disable their box.)

It may not be a box? in recent years some providers control your unit(s) via a smart thermostat provided by them. (people love their nests for strange reasons, until the HVAC stops blowing cold... then they proclaim it's not the nest the pro nest people want you to remain a nest person so they get a trouble call.)

If the electrical problem is inside the HVAC unit itself, you are typically going to need an HVAC guy. Electricians are primarily used for connecting to the electrical panel, unless they hold an HVAC license besides an electrician license.

I service the Katy, Texas area.

Hi all,

Just an update. My meddling prompted my parents to make an appointment with their electrician, who confirmed the unit DID have power, according to my mom. My step-dad did not seem convinced. The electrician recommended their HVAC tech come out, so he did. And this time, they found the problem. It was an HVAC problem. So, glad the problem is fixed. Time for another family talk about future plans. 

DTE may not cover themselves with glory on a regular basis, but this time it really wasn't their fault.

If your HVAC contractor doesn't have the ability to confirm or deny that the equipment does or doesn't have power, it might be time to use a new HVAC contractor.

Certain power issues could require an electrician, it's note worthy in your response that the electrician couldn't fix the problem, recommened HVAC come out.

Just appears to me from this distance that your HVAC guy may be the weak link.

I've had issues of missing leg from the pole, this isn't that difficult to figure out and I am not an electrician.

Power problems from the pole is going to require utility people.

You can't come to conclusions of this nature by just checking for power at the equipment itself. Then you have to identify sub panels (if any) from main panel.

From the phone conversations with my mom, it sounded like there were two weak links....the HVAC company (they have previously said there was no trouble with their equipment, and it turns out there was), and my step dad (my mom had just finished telling me that the electrician was confident that there was no trouble with the electrical supply to the HVAC system when he said he wasn't so sure about that).

It certainly seems like a problem that could have been solved a long time ago.

It sounds that way to me too.