The many joys of homeownership

[AkioOhtori]

Yesterday I was attempting to clean the garage last night as the president of the local Alfa Club is coming over to look at my car and I figured if he saw the squalor it usually lives in he'd take it to a shelter or something. Anyway, walking through the house I notice it is gross downstairs. 78 and humid. 78 is a normal setpoint for us, but I'm an adult so I crank it down to 75. Come back a while later and notice I'm only getting tepid air.

Terrific.

Ok so I go over to the unit and it is, in fact, not running. This is somewhat good news as that likely means it hasn't frozen or exploded or whatever. I pull off the side and check the contactor I installed a couple months ago. Working. Cool.

Crap that was like... my only thing.

I guess I should check supply voltage?

My house is a little over 100 years old, so the electrical is a little... eclectic, lets say. The main 200A panel is new, but it has 2 sub-panels, each of which also have sub-panels for no discernable reason other than history and tradition. Anyway, the AC is run off of some fuses next to it, so I didn't think that little tidbit of information would be relevant. Hint: it is.

Pull the fuses and check them. 0.2 Ohms. Good stuff.

Tentatively stick my meter into the (literal) fuse box to check the hot side has power. I am a fairly confident around industrial power systems, but for some reason home wiring always surprises me. And by "surprises" I mean "blows up unexpectedly". Anyway, after some careful prodding I get no voltage. After some less careful prodding, I still get no voltage.

Maybe I'm sticking it in the wrong end? (Heyo)

I check what I would call the load side and still get no love.

Curious.

I go in search of my voltage probe (thing that beeps when there is live AC) and find it out of batteries. Put a new battery in and find that it beeps constantly. Look inside and it has a lot of corrosion. Neato. INTO THE GARBAGE WITH YOU THEN.

Ok. Well I guess I need to find where that fuse box get fed from. Luckily it is fed with conduit, so I follow it into one of the hateful sub-boxes an find an unmarked 50A 2-pole breaker. Seems sus, but looks closed. I pull the panel cover and confirm that yes, that is what is feeding the fuses. I turn it off and back on again and SUCCESS! AC kicks on! All is well! I fixed the problem! Nevermind why it tripped that is in the past!

I button everything up, pat myself on the back, and go back to working in the garage. (I think we all know where this is going.) About a half-hour later I go inside and... AC isn't running.

Cock.

Remembering that I bought a clamp-meter this year, I fish that out, re-remove the panel cover, reset the breaker, and put a clamp on one of the phases.

13.9A

Seems... reasonable? Certainly well under 40A and 50A. I leave it run for a while and it holds steady.

Other phase was similar. Crap. So.... bad breaker? Is that even a thing!?

Oh wait! I have a thermal camera in my phone!

Uhh.

Ok yeah. This is my first "breaker thermal photo" but one of those seems A LOT hotter than the others. Certainly couldn't hurt (much) to replace. What even type of breaker is this? It doesn't look normal and I seem to recall that last time I looked it... isn't.

TINY little sticker on the breakers say Z-something. Maybe google will help.

Zinsco. Huh. The first hit is a wikipedia article. That seems... bad.

The copper shortage of the 1960s was primarily caused by the US government, which had huge contracts out, many of which were for air-conditioning, requiring over a million new copper coils. This action depressed the market of available copper for other manufacturing needs and promoted the first real demand for aluminum NM cable. When Zinsco changed to an aluminum bus, the aluminum selected was Alloy 6061

Oh dear. I think I know where this is going...

Currently, Zinsco electrical equipment is considered obsolete due to a design flaw in which the circuit breaker's connection to the bus bar becomes loose, causing arcing and subsequent overheating. Long-term exposure to this heat can cause the breaker to fuse to the bus bar, making it impossible to remove. Even worse, it can cause the breaker's contacts to fuse together, thus preventing the breaker from tripping even in an overcurrent situation, thereby causing a potential fire hazard.

Terrific.

Well... while I WILL (eventually) replace these panels, today is not that day. A quick trip to Home Depot says I'm SOL, so my good friend Amazon has three breakers on the way. (One for each AC unit plus the garage apartment, which are the three large loads on those panels.)

So TIL I have a little bit of history (that I never wanted) in my house and yet another thing to worry about. On the bright side, new breakers (or new breaker boxes even) are way cheaper than a new AC unit!

[pyroholtz]

@akioohtori great write up, I felt like I was right there with you the whole time, certainly laughing with you (at you?) during the comical parts.

Old electrical is like old plumbing; always exciting, hardly predicable and when it works, you leave it completely alone and hope for the best.

[HoustonRunner]

@akioohtori Those FLIR cameras are so cool! Don't have one yet but want one.

I've wanted one for a while for pheasant hunting. Not to track them to shoot, but to find them after being shot. We lose 20-30% of downed birds with a dog, and 50% when we don't have a good dog with us.

But generally the ground is cold and the bird should still be warm, so I've always thought it would be a great way to find a downed bird.

[facw]

@akioohtori said in The many joys of homeownership:

I turn it off and back on again and SUCCESS! AC kicks on! All is well! I fixed the problem! Nevermind why it tripped that is in the past!

I had this experience with my bedroom AC in my apartment in NYC. After two failed resets, I decided I really did need to get maintenance up there, and it turned out something was arcing in the enclosure.

Also one 1970s subdivision I lived in as a kid has widespread use of aluminum in the electrical panels, and yeah I watched a house burn to the ground because of it. We got our remediated...

[AkioOhtori]

@houstonrunner They're a lot of fun! Depending on what you're hunting it that might work, but might not. One thing is they can't read through things, so if there is grass, shrubs, etc in the way it'll just read that (sort of...). Also a lot of FLIRs are shockingly low resolution. I don't remember the exact numbers, but this one is something like 40x60px or maybe even less. It uses a normal optical camera and interpolation to make a reasonably high quality photo. The net effect, however, is you can't really see very far with them. We tried it while hiking and the humans disappeared from thermal view after about ~50 feet, though they were still VERY clear in optical.

[ibRAD]

@houstonrunner I considered one before. A good FLIR scope is in the order of a couple grand though. Also potentially very illegal depending where you are. I decided I didn't like eating rodents that much.

[AkioOhtori]

@ibrad @HoustonRunner Oh hey yeah I forgot you could buy hunting specific ones... That makes more sense.

[Roadkilled]

@akioohtori My last house had a Sylvania panel with the same design as the Zinsco breakers. In my nonprofessional opinion, it's worth replacing that panel. It's not as bad as Federal Pacific panels, but it isn't worth keeping.

My house had a copper water line running horizontally over the Sylvania panel. The electrician upgraded the panel to 200 A service, which meant a taller panel. I got home on a hot August day in St. Louis to find the new panel installed, the air conditioner breaker off, the door closed and the water line running over the door. The electrician installed the taller panel behind the water line. There was a note taped to the panel saying that the plumber would be by tomorrow to reroute the water line. I was able to open the door just enough to turn on the breaker for the air conditioner.

[AkioOhtori]

@roadkilled Oh yeah for sure it'll get done when the garage remodel happens. Basically paying $150 to kick this can down the road for a year.

[LooseonExit]

@akioohtori said in The many joys of homeownership:

Currently, Zinsco electrical equipment is considered obsolete due to a design flaw in which the circuit breaker's connection to the bus bar becomes loose, causing arcing and subsequent overheating. Long-term exposure to this heat can cause the breaker to fuse to the bus bar, making it impossible to remove. Even worse, it can cause the breaker's contacts to fuse together, thus preventing the breaker from tripping even in an overcurrent situation, thereby causing a potential fire hazard.

LOL. That's definitely very very very extremely bad ideal in case of overcurrent.

Also, good read. Well done.

[2 Jeeps and a Mustang wants a Fiata]

@akioohtori Everytime I see your FLIR camera I wonder why I dont have a CAT phone despite working for them.

[Shop-Teacher]

@akioohtori Wow, what fun! Bad breakers are indeed a thing, but obviously you have more to deal with there too.

[HoustonRunner]

@akioohtori @ibRAD I was definitely spoiled early - internship in college was for Texas Instruments back before they sold the defense business to Raytheon. I worked in the group that made the infrared detectors for the fire and forget anti-tank missile and the FLIR pods on the Apaches. Those things were amazing, and working there gave me some appreciation for military costs.

[rctothefuture]

Gotta love AC units!

Ours was working this summer, until the fan stopped working. I went out and found the fuse from 1986 for the fan finally popped. Had to scour ebay for a suitable replacement and $50 later it was back up and running. Home ownership is just the best!

[MM54]

Mmmm, one step up from a federal pacific box. Worth replacing before it decides to, at best, stop working (or burn the place down, at worst).

[VincentMalamute]

@akioohtori That's very lucky the breaker did that before fusing itself to the buss bar. This completely justifies the cost of buying the camera! You're persuading me to buy a FLIR phone attachment.

[AkioOhtori]

@vincentmalamute Well... I haven't tried to remove it yet so... TBD if it is removable. On the bright side there is a ton of room in both boxes (I think they used to be the main boxes) so I can always just disconnect it and move the load down the line.

[ranwhenparked]

@akioohtori My cousins' mid 60s house in Pennsylvania had that stuff, they specifically bought it vs their second choice, an 18th century farmhouse, because they figured 1960s would be modern enough to avoid unexpected troubles. Nope. I think I'd gladly take a well maintained 1920s knob and tube system over that, at least K&T wasn't essentially defective on the day it was installed.

[pip bip]

@akioohtori that's not good.

[Engineer In Motion]

@roadkilled oh dear god, definitely need PSA on Federal Pacific panels especially the really old ones. If anyone sees one DO NOT TOUCH IT, stay the hell away from it unless it is your job to work on it.