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America's new millionaire class: Plumbers and HVAC entrepreneurs

(www.wsj.com)
185 points hhs | 20 comments | 13 Oct 24 15:35 UTC | HN request time: 1.253s | source | bottom
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elawler24 ◴[13 Oct 24 22:07 UTC] No.41832117[source]▶
My dad bought a failing HVAC business 30+ years ago, then made it profitable over the years and sold it back to his employees last year. He had the option to take a few highly lucrative PE deals, but it was clear they would squeeze the life out of the employees and customers he had worked hard to support over many years. I can’t imagine how low quality this kind of trade work will become if PE owns them all. It will be similar to vet, dentist, and dermatology clinics which now feel like factories that don’t care about the humans on the other end - often employing fear tactics and sales quotas to incentivize upsells.
replies(6): >>41832219 #>>41832220 #>>41832549 #>>41832822 #>>41841303 #>>41842080 #
heymijo ◴[13 Oct 24 23:56 UTC] No.41832822[source]▶
> often employing fear tactics and sales quotas to incentivize upsells

This already happens. The most common AC repair needed is a new capacitor. It's a $20 part.

Call your dad's business, you probably get a quote for $100-ish and it's fixed in ten minutes.

Call a PE owned shop and they are likely to tell you that your entire system needs replaced. Quote $5-$8k.

Reports like this are already common place, and the roll-ups of former small-businesses in industry like HVAC that the PE people celebrate will only make this worse for customers.

replies(5): >>41833242 #>>41833429 #>>41833524 #>>41834933 #>>41838204 #
1. nradov ◴[14 Oct 24 02:03 UTC] No.41833524[source]▶
Could someone ELI5 why AC capacitors are so fragile? I had one fail last year on a unit that was just out of warranty.
replies(5): >>41833841 #>>41833876 #>>41840045 #>>41840246 #>>41897194 #
2. gh02t ◴[14 Oct 24 03:02 UTC] No.41833841[source]▶
Most are electrolytic for practical reasons including cost and available capacity+voltage rating. Electrolytes in the capacitors dry out in the hot weather as well as other things like other components going bad and drawing too much current, both of which cause further overheating. Overheating makes the electrolyte dry even faster (making the capacitance plummet and resistance increase, i.e. stop capacitoring) and generate gasses (=>swell/pop).

Tldr hot weather is hard on them. They have a finite lifetime and suffer most when you need the AC the most.

replies(4): >>41834392 #>>41834931 #>>41836281 #>>41840234 #
3. lazide ◴[14 Oct 24 03:10 UTC] No.41833876[source]▶
It’s not so much that they are fragile, as they’re a part that gets a lot of very heavy duty use and they’re expensive to make invulnerable. Ain’t no residential customer going to pay for a 100mfd 240v tantalum cap (how big would it be even?).

Think of them like a car starter motor or transmission (for old ICE vehicles).

Assuming we’re talking motor start capacitors anyway. For most of them, every time the compressor starts they see a dead short at 240v for a couple milliseconds, typically in the 10,000+ amps range.

And most people use their AC the most when it’s hot and nasty out. Which doesn’t help.

replies(1): >>41833926 #
4. halper ◴[14 Oct 24 03:25 UTC] No.41833926[source]▶
By "mfd", do you mean µF? I have some basic knowledge of electronics and am not familiar with "mfd" in this context but assumed you must mean microfarad.
replies(1): >>41833944 #
5. lazide ◴[14 Oct 24 03:33 UTC] No.41833944{3}[source]▶
Apologies, yeah most motor start caps for some reason use mfd to mean micro farads. [https://www.packardonline.com/electrical/capacitor/motor-sta...]

I guess from before the days of Unicode?

µF == the same thing, but tends to be the ‘more correct’ modifier used in electronics and engineering, rather than industrial parts supplier catalogs.

replies(1): >>41834534 #
6. steve_adams_86 ◴[14 Oct 24 05:12 UTC] No.41834392[source]▶
Are more robust capacitor designs not an option because the capacitive properties of the paper ones are better for the use case?
replies(1): >>41835975 #
7. carlmr ◴[14 Oct 24 05:42 UTC] No.41834534{4}[source]▶
Oh, wow, this is so bad. m usually means "milli" not "micro". At least they could have used u instead of µ, which is a more common replacement when you don't have the keyboard character available.
replies(1): >>41834642 #
8. lazide ◴[14 Oct 24 06:02 UTC] No.41834642{5}[source]▶
Just wait until you see the actual dimensions of a 2x4!
replies(1): >>41835996 #
9. himinlomax ◴[14 Oct 24 06:58 UTC] No.41834931[source]▶
Aren't electrolytic caps polarized? That can't be used for AC. Iirc these capacitors are film types instead.
replies(2): >>41835931 #>>41836260 #
10. ssl-3 ◴[14 Oct 24 09:55 UTC] No.41835931{3}[source]▶
Non-polarized electrolytics are somewhat uncommon, but they definitely do exist. They get used rather frequently in things like crossover networks for loudspeakers[0].

They tend to cost more, and tend to be larger than their polarized kins. They're not advantageous in circuits that always have some DC bias, so they only get used where it is necessary.

0: https://www.bennic.com.tw/en/ec/index.asp

11. ssl-3 ◴[14 Oct 24 10:02 UTC] No.41835975{3}[source]▶
More robust capacitors exist. They just cost more.

In HVAC world, the practical differences between a motor start cap and a motor run cap are price, physical size, and longevity.

A start cap is cheaper, but is meant only for intermittent duty and is unsuitable for use as a run cap.

Meanwhile, a run cap costs more but can serve as a run cap or a start cap.

All things (except for outliers like the McLaren F1) are built down to a price.

12. ssl-3 ◴[14 Oct 24 10:05 UTC] No.41835996{6}[source]▶
I owned a house once that was balloon framed, with 2"x4" black walnut studs in the walls.

They just don't make things like they used to. :)

13. ◴[14 Oct 24 10:47 UTC] No.41836260{3}[source]▶
14. trq01758 ◴[14 Oct 24 10:50 UTC] No.41836281[source]▶
For AC these units use non polarized, oil-filled metallized polypropylene film capacitors. But overheating is a problem for them, as it is for electrolytics.
replies(2): >>41840066 #>>41851279 #
15. Log_out_ ◴[14 Oct 24 17:58 UTC] No.41840045[source]▶
You can control when a capacitor will blow, by placing it at a certain distance to a heat source. They do not like heat and you can thus determine the lifetime of a device on a bell curve around time * times constant average use. Nasty but legal.
16. Log_out_ ◴[14 Oct 24 17:59 UTC] No.41840066{3}[source]▶
Would be neat to have an AC to keep the electronics nice and cool.
17. sidewndr46 ◴[14 Oct 24 18:13 UTC] No.41840234[source]▶
No one uses an electrolytic type capacitor for the 60 Hz winding of a "single-phase" induction motor.
18. sidewndr46 ◴[14 Oct 24 18:14 UTC] No.41840246[source]▶
They aren't. The ones you buy nowadays just aren't engineered to last.
19. gh02t ◴[15 Oct 24 18:05 UTC] No.41851279{3}[source]▶
Indeed, I did some basic double checking before I posted but I guess the info I read was bogus+I was also having a brain fart to not know better because you're definitely right. Thanks for correcting.
20. rasz ◴[20 Oct 24 17:59 UTC] No.41897194[source]▶
Electrolytic capacitors are a perishable good. Age even when sitting on a shelf unused.