Thursday, December 16, 2010

Teching And Bodging

The previous post and some of the comments got me to thinking about what I will and won't do, technology-wise.

The trade-offs are time, skill, tools and trouble. We needed a new garbage disposal last week; I hired it done. It's not that hard to replace the things and it'll save almost $300, but I was very busy with work and it is a royal pain wrestling 'em into position; I paid a plumber to do it. For other plumbing, it depends on the pipe; all the half-inch copper accepts those nifty push-together fittings. There's some plastic pipe with crimped fittings in the system, though, and I don't trust it nearly as much. I'll probably end up paying a plumber to change out critical bits to copper, when it needs it, and finish it up myself.

I paid an electrician to install new receptacles in my bedroom and the washroom, plus a vent fan in the latter. I could have done it but I don't like opening up a panelboard when I'm by myself, plus he did a much neater job than I could have. On the other hand, I had to point out where he could install the new breakers by removing an unusable range circuit.

On my MGB, I would do everything but adjust the carburettors and valves and major engine work. The first takes experience to do well and the second, well, the procedure is insane, not to mention messy; the tiny engine has to be warmed up, shut off, valve cover yanked and everything set quickly before it cools off; a really cautious mechanic slaps the valve cover back on and has you drive it around the block after he's got halfway so it stays warmed up. I let the shop (gone now and much missed) change it over to electronic ignition, too. (The old distributor conked out and that particular version wasn't available -- they had several different curves for the vacuum advance, to match the carb needle valves. Electronic retrofits can fake it). On the other hand, I've installed new gas tanks and gauge sending units, thermostats, a clutch master cylinder, even changed out a driveshaft U-joint and replaced the front disc brake pads and flexible lines. Newer cars, I'm done at plugs, filters and driveway oil changes -- and it is so much easier to drive through for the latter now.

So it depends. But I still think one ought to at least know enough to see if the hired help is doing a good job or not.

A local HVAC outfit managed to put themselves on my "never hire" list when I was buying this house. On inspection, there was a crummy so-called permanent filter in the furnace, gummed up and flapping in the airflow, too small for the opening. The inspector and I requested it be changed to a proper-sized pleated filter and sure enough, the seller had his long-term HVAC guys do that and included the receipt in the paperwork, showing the work had been done. The first time I went to change the filter? You guessed it. The very same lousy filter. They'd done nothing. And been paid for it.

The basics are not that complicated -- hot on the left, cold on the right and drains run downhill; live wire is the narrow blade, black wire; neutral is wide blade, white wire; ground is the green or bare and the U-shaped pin.* Flues gotta connect, filters need to be tight all the way round and if you can't see light through them, they're probably toast. Reader's Digest turned out a "home handyman" type book and it (or a similar tome) is worth owning even if you never do any of the fixing yourself, because it will tell you how the fixing should be done. You don't need to be an expert, you only need to be able to read and to think -- and to know what your own limits are.
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* Unless you don't happen to live in North America. Elsewhere, if you are lucky, you'll find the new "universal" color coding: hot wire is brown, toasty brown; the neutral is blue, cool blue; the ground or earth wire will be green with a yellow stripe. But older homes? Could be anything, check your local codes and practices and ditto on how to wire up sockets. UK and Commonwealth counties with 220-240V mains may find red for hot, black for neutral and clear for earth but do NOT take my word for it. Adjacent countries used the same or similar colors for different functions; way back when, they didn't compare notes and there were only so many colors available. The U.S. practice of using white for neutral supposedly comes from electricians marking the return wire with chalk back when black rubber and cloth insulation was common.

12 comments:

og said...

I'm not smart enough to shy away from anything.

There are things I don't like to do, like auto body repair, or drywall mud, or trans repair. Those things give me the biggest trouble. I still get called on to do them anyway. I ended up mudding the walls of our hunting cabin just because everyone else was 100 times more inept than I. I like doing woodwork because I'm good at it, having been a cabinetmakers apprentice some years ago; I also like weld and fab, but don't get to do as often as I'd prefer.

John Peddie (Toronto) said...

Cardinal rule: You're not likely to drown by DIY plumbing; serious electrical stuff, however...well, there's a reason they call them electric chairs.

Nathan said...

I will say that when the A/C went west on the last day of the cooling season this fall, I said, "I'm not going to fix it, I'm going to hire it done." Even though I have the skills, at my age and girth I simply don't feel like climbing around in the attic running new refrigerant lines and suchlike.

Plus, I want somebody else to hold the warranty. That will be a first.

(Remind me Sunday to ask you who your HVAC people are...I remember you saying you used a family-owned company, and I figure I'll give them a shot at quoting the replacement.)

Stranger said...

Spark plugs are a snap - until you must either pull the engine or drill holes in panels, or the firewall, for access. Then they become a major pain - for the repair shop.

Otherwise, I just make time and do it. Of course, that is much easier since I sign the paychecks.

Stranger

Old Grouch said...

Re: Color codes

Brings to mind the tech-geek joke in the Beatles' Help about "Earth's green in America." (If you don't recall it, ask me Sunday.)

Anonymous said...

I remember a certain group of office equipment made by a former employer of mine that, save green for grounds, had every wire in it black. One had no choice but dig out the meter and schematic and do point-to-point to figure out which was what. Hemorrhoid surgery with a butter knife would have been more pleasant. And probably faster...

Nathan said...

We had an electrician come in one time at work (a long time ago and the wench is dead...probably) to wire up a single-phase 208 volt outlet for a very odd UPS we'd purchased along with a certain piece of DEC equipment.

So this guy wires it with a red wire and a black wire and no ground.

He had left the office (but not the building) when I discovered this, and I lit out after him and dragged him back. He said, "Well, the Greenfield [the flexible metal conduit for the uninitiated] is the ground. That's according to code."

I said, "Son, I've been an electrician for half my life [I think I actually had been at that point] and that's not according to any code I ever read."

He said, "Well, it doesn't need a green ground wire."

I said, "Well, I'm the customer, I'm paying the bill, and I say it does."

So he grumbled and unpacked and ran a green ground wire through the Greenfield six whole feet to the panel on the other side of the wall.

I'm sure he thought I was an old grump (or worse, but this is Bobbi's site), but in my life I've seen too much Greenfield break loose from its moorings to ever trust it as an equipment ground.

My guess is that this guy subsequently electrocuted himself at some point on a piece of equipment that wasn't grounded because the Greenfield had come loose and there was no ground wire in the bundle. But of course I have no idea.

Wayne Conrad said...

I had a big-box hardware clerk tell me you could run two 20-amp circuits on a 12-3 cable, using one wire for a common neutral, and each of the two hots going to a separate leg on a two-phase panel. I'm no genius when it comes to house wiring, but it seems like that would ask the neutral to carry 40 amps under full load. Worse, the two 20 amp breakers would be quite happy with that. Am I wrong?

A friend once told me that you can run 20 amp circuits on 14 gauge wire. I don't know, but I thought you needed 12 guage. His reasoning is that house wiring is overspec'd. My reasoning is that engineering margins are there as... well, margins. So that material and manufacturing variations, among other things, don't cause your house to burn down--not so that you can spend a little less on wiring.

Besides--If your house burns due to something you did out of code, what will the insurance adjuster do when you submit that claim?

Ritchie said...

I once worked at a SoCal company that was webwired over the suspended ceiling in at least 2 color systems, and plumbed for compressed air, vacuum, nitrogen, chilled water and hydrogen. I did try to be careful.

Roberta X said...

Rithcie, batter you than me. Way better. :)

Wayne: Actually, that trick is pretty common and -- prior to modern computer-type power supplies -- it works great. In household wiring, the two "hot" sides are 180 degrees out of phase and the worst-case neutral current is only 20 amps. With balanced loads on each side, say 100W lamps one each one, neutral current is zero. Neutral same size as phase wires is still standard practice.

The rub is harmonic currents, which you get from some switchmode and linear supplies as found in modern electronic devices. They may not be exactly out of phase and if so, will add rather than cancel. The rule of thumb if sharing neutral is to go to the next larger standard size; if the circuit used #12 for the phase wires (20 Amps), then use #10 for the neutral. Or just run a same-size neutral for every branch circuit, which is SOP where I work.

Nathan: Greenfield! I hate that stuff. Armorflex is fine (and easy), sealtight is AOK, but frikkin' greenfield...! I'm with you, never ever rely on the conduit for ground. Sometimes I have had to in old, old homes but it's a bad idea.

Douglas2 said...

No one told the previous owner of my last house about that "drains run downhill" thing.
Current place has NM cloth romex with ground, but the ground wire was just connected to the box with a little clippy thing.
I had an electrician firm do a service upgrade, new circuit panel, and grounded outlets (shuttered) everywhere, and only months later noticed that they didn't bother to pigtail the ground to the ground screw on the outlets, it is still only grounded via the clippy thing to the box.
I suspect it's to code, but wouldn't you choose to connect something to that green screw if it's sitting there in front of you?

Roberta X said...

Douglas, AFAIK, the current practice would be run a green wire from the green screw on the socket to a (green) bolt in a tapped hole on the box. If the box is recent enough to have the magic tapped ground-screw hole, that is.

As for the "clippy thing," some of the quick-connect ideas are good and some aren't....

The preceding is just talk, not professional advice; I am not a licensed electrician (not that they license them in Marion Co). Consult local codes. YMMV. Dealer prep and destination charge not included.