Because the comment is just a copy/paste of the content at the URL at the top of the comment; which doesn’t add anything to the discussion, because it’s not discussion at all. It’s just a wall of text, it’s not clear to me why you’re posting it as a comment (vs linking to it), and simply regurgitating copy/pasted external information isn’t helpful or interesting.
Next time, write a sentence or two of context about what you’re going to link to — who wrote it and when, why it’s interesting, and how/why it’s relevant to the topic at hand.
There’s almost never a need to copy/paste wholesale external content into an HN comment. Especially true when said content is literally linkable, and actually linked, from your comment!
I'd probably suggest checking out Reddit (r/hvac for pros, and r/hvacadvice for homeowners) -- you'll generally get really good advice, often from professionals, if you provide good inputs/context.
If you have 2+ floors, you probably need (or have) zones, and it may be worth paying a professional to engineer a solution that meet your requirements. I recall finding some small businesses online that do exactly this for a nominal fee (<$500 IIRC).
You might also consider looking for residential HVAC companies that also do commercial refrigeration; the conceptual physics for commercial refrigeration aren't much different from residential HVAC, just specialized refrigerants & components that are tailored to those use-cases (ie labs often require extra-cold freezers, etc).
FWIW, my gut is you'd be happy with most variable-speed offerings, if sized appropriately. Low humidity here makes it easier, but I'm sure you can do what you want, but it may not be cheap.
If you remove the service panel there's a screen that displays what capacity they're running at. My installer had some issues initially, and Bosch actually had 2 regional reps (corporate) visit the site themselves. I'm sure the protocol exists somewhere, but the guys they sent wouldn't have known and I don't believe they connected anything to the board -- the Bosch reps couldn't even correctly explain to me how/what logic controls the speed of the interior blower fan (two speed).
I actually never really did get an answer to that question -- what/when will the interior fan go to it's "second speed" (when only sending 1 cooling signal & letting the Bosch board have 100% control over capacity), so we ended up wiring my units to be "remote" controlled, like a 2-stage system - though it's then critical to enable an extra setting ("Reverse Staging" on Ecobee), otherwise you'll just end up with short-cycling when stage2 cooling calls are made. If you search the topic you'll probably stumble on my Reddit thread which has quite a bit of detail on the topic. =D
I wish you luck; I do think it's the future. FWIW I think your product's ideal audience/target market is probably not here/us, but I think a relatively large addressable market does exist. How you can best reach & tap into that market, at a price point that make sense & while providing a (sales) UX that actually converts -- I think those are the main challenges you'll have to solve.
Sounds like you may have had a whole-home energy audit done already -- including a blower door test? If not, I'd highly recommend it; I paid ~$500 for one a few years back which included thermal imaging, blower door tests, airflow measurements & calcs, current/draw measurements for all energy-consuming devices, thermal load calcs, etc. You may find better pricing even -- ours included a detached structure/office, and house is relatively large, multiple HVAC units/solar/pool/servers/etc...
In my case, I didn't end up with any super directly-actionable insights -- but it was still very well worth the money IMO. Even just to confirm that we weren't losing/"leaking" energy egregiously. The reality was, our household simply uses a lot of energy - hah.
I mention this all because, at the time, we were just about to replace our HVAC units & we had just installed solar + storage.
I'm located in Las Vegas -- summers are HOT (!) -- but our units (2x 5-ton Bosch heat pumps) can near-trivially keep us at 70F (or cooler), even on the hottest of days. I try to "push" the thermostats up a bit (we leverage a ToU energy plan), but there are days when the battle isn't worth having & the wife needs it at 69F -- and, even on the hottest Vegas days, we're able to hit it (can be expensive to do so, depending on time of day -- but is totally doable).
Edit to add -- Oversizing a system can very easily lead to issues; short-cycling, humidity control, etc. The ideal system will run nearly non-stop on "design" temperature days.
See if you can find any highly-rated Bosch installers locally; they'd likely be willing to "oversize" a system since the Bosch units are "variable capacity" (inverter-driven), which means you're less susceptible to hitting some of the common issues/concerns when oversizing traditional systems. Alternatively, the high-end variable-speed options from major brands are generally well-regarded though they can be extremely expensive (the price segmentation, and resultant value propositions, are bordering on dubious IMO).
Wish you had been around a few years ago, before I took the plunge on two 5-ton Bosch "BOVA 2.0" heat pump units -- I'd have seriously considered your product.
The Bosch units are inverter driven and contain some interesting tech; we've had some issues with them, unfortunately I'm not sure that the HVAC industry is ready for such tech, but I do generally think it's the future.
I continually wish (and search Github bi-annually for) there was a way to see what frequency ("capacity") my BOVA units are running at -- aside from just being able to see the "staging" (purely controlled by temperature delta via Ecobee). There's a USB port on the board, but I can't find any info/data on it & obviously I don't want to take chances on >$15k -worth of HVAC units. But it'd sure be nice to see, at the very least, what the capacity/frequency is -- without having to physically take screws out to remove the panel covering the board.
Alas, maybe some day -- perhaps once my units are out of warranty I'll be daring enough to try and get something from that (very tantalizing) USB port.
Me too. Usually the pilots will mention it if they receive an RA, though. I think TCAS might even be disabled (or nerfed?) at low altitudes like this -- not positive, though.
From what I've read, it sounds like this airport is not equipped with the ATC-equivalent of TCAS -- which I think would have been sounding all kinds of alarms (how early?) in the tower for a scenario like this.