What Causes Compressor Leads to Burn Off of Terminals?

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For the 12 years we've had this condenser unit the compressor leads have burned off at the terminals once or twice a year. These events burn the insulation off the wires back about 3 inches from the connection, and seem to char the wire itself to the same point but it may just be the burned insulation making it look like the wires were burned.
For the 10 years my unit was under warranty I simply called the people who installed it, they'd come out, cut off the burned wire ends add some inadequate crimped on connectors and it would work for 6-12 more months. Now that the warranty has run out this has become my job. This summer it's begun doing this more frequently and the events seem to be getting closer and closer together. I'm pretty sure this even happen upon startup because I've heard the breakers snap a couple of times shortly after the indoor fan comes on, and when I go out and look the leads are burned.
Based on advice I got here I installed a set of Term-Loc leads about 6 weeks ago. A week ago these leads burned (just like the old ones). The connectors stayed on but one lead burned completely off its Term-Loc connector. The event melted/burned up the plastic terminal separator that comes in the Term-Loc kit. I wasn't able to attach the burned off lead to the Term-Loc connector again, so I went back to my old method that used to last 6 months to a year. Night before last the same lead burned off again.
My question is, what causes compressor leads to burn off of terminals repeatedly like this? Remember it has been happening fairly regularly for 12 years so it isn't a condition caused by age.
This unit has a black cylindrical thing connected to the run capacitor. It has the name Supco Super-Boost. [See picture
http://img150.imageshack.us/img150/8528/supcop7315937gi9.jpg] It has words on it that sound like it's a compressor start booster. Suggesting it gives the compressor a big current hit on startup to kick the motor into motion. Could this be causing the wires to burn? If so, why do I need it and can I remove it? If I can remove it, do I just disconnect it from the start capacitor?
-- Ken
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On Fri, 29 Sep 2006 23:33:44 -0500, Ken Hall

Your thermostat is causing "high voltage crossover" at the contactor where the two wires come into the condenser from the indoor circuit board. Replace the thermostat and all will be well. Such a simple fix, you must of had an idiot working on it.
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I see a pattern here: you are the anti-stormy.
Stormy tried to fit it by being nice and offering poor help. you try to fit in by being a prick and offering Bubba-ish help.
Bubba wins, but you are his protιgι, I guess? Bubba at least seems to know what he talks about. You are years away from that. If you think his compressor is bad, why don't you mention that?
Dimwit (at least I admit it) sprinkler system armed
wrote:

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wrote:

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Ken, The answer to your problem at: http://americanhvacparts.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=REL20171&Category_Code Jabs
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http://americanhvacparts.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=REL20171&Category_Code =
Damn... how can they sell them so cheap? LOL
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They not HVAC contractors! They're a real business!
Jabs

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If they were a "real" business, they would charge enough, at this point they are only charging a 4times mark-up.
wrote: >

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Steve, .....for 1.6’ worth of plastic & 5.4’ worth of electrinics? Try 62,485 times mark-up! Steve, I know you're an excellent HVAC Technician, just a dumb-ass businessman!
Jabs

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Actually I do carry "rescue wires"(Term-Lok wires) on the truck and they are only $51 each *installed* :-) They cost a bit more than you proported 6 cents per wire.
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Noon-Air wrote:

I've used term-loks for other motor applications as well... a decent design and a real brass alloy lug... nice....
$51 bucks installed ain't bad, Steve.
Jake
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Is your name spelled correctly at the end?

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wrote:

So you mean I won a prize? Just forward the money to my PayPal acct. Bubba

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the prize committee budget is poorly funded; best we can do is send you a slightly used 5 cent cigar that was used by some porno queen showing off one of her many talents. Just saved up enough bottles and cans to get enough cash to fine dine at Burger King.
I love this group. ( hey!, but only in a plutonic way).
snipped for; cause I want to
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The initial problem may have happened because the connections were not tight enough. That causes resistance that generates a lot of heat that turns the terminal on the compressor into resistive poor conductors therefore the scenario keeps repeating.
They need to take some emery paper and tire to get down to a better conduction surface. Also, is the compressor running too hot?
If the compressor terminals appear to be too burnt & emery or filing does not help along with special screw tight terminal clamps, then eventually it will get to hot & blow a hole in the terminal plug, resulting in the loss of all the refrigerant. - udarrell
--
Air Conditioning\'s Affordable Path to the "Human Comfort Zone Goal"
http://www.udarrell.com/airconditioning_eer_ratings_over_seer_ratings_central_systems.html
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That was a terrific photo of the boost kit in the connection box. I wonder if the gentleman with the unit would be kind enough to post anohter pic, this one of the terminals.
That's something I'd not thought of, bad connection inside the compressor. Of course, where the terminal block ataches to the internal wiring may be high resistance.
And my favorite reccomendation -- clean the condensor.
--

Christopher A. Young
You can\'t shout down a troll.
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Thanks for your reply.
wrote:

When I installed the Term-Loc connectors I used sandpaper to try to clean the terminals, but they're pretty burnt after all these incidents. I considered filing them but the location is too awkward for that.

I don't know how to judge too hot. I can put my hand on it be I can't leave it there.

That's what the Term-Loc connectors are. They have a set screw that screws down onto the terminals.
-- Ken
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Sounds too hot.
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Christopher A. Young
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Sounds like a bad or improper thermostat is being used. What make/model thermostat do you have?
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wrote:

That's baffling to me. How can a thermostat cause this? As far as I know all the thermostat does is supply 24v to energize the contactor when cooling is called for.
My thermostat is a Honeywell Chronotherm III.
Incidentally if you're thinking the contactor is chattering when energized, it's not. There's just one solid clack.
-- Ken
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