Help with Expobar wiring short

Equipment doesn't work? Troubleshooting? If you're handy, members can help.
Jtr71

#1: Post by Jtr71 »

So my Expobar thankfully set off my breaker before it started a fire but the two wires that connect to the on off switch burnt up. Should I be concerned about what caused or should I just try to replace the wires?


JRising
Team HB

#2: Post by JRising »

Those wires have been over-heating for a while and the insulation hardened, cracked and fell apart at some point a long time ago. The steamy, possibly acidic environment has been oxidizing the exposed copper for a while, reducing it's capacity and making the heat issue worse over time until this result.

Replace the obviously bad wires with high-temp, 14 gauge. (I know your old ones look like 16 gauge, they probably are, but improve on the things that have proven to fall apart sooner than you'd like). Check other high current wiring throughout the machine, for example at the pressostat and at the element. If the insulation is hardened it will crack soon. if it's already cracked, now's the time to replace the wires before they become... Well, see above picture.

Lastly: The corrosion makes me suspect a very humid and possibly acidic environment. Check the vacuum breaker, is it spitting up on the boiler-top components right before it closes? Is the boiler maybe overfilling, allowing too much liquid water to get out through the vacuum valve? Once closed is it a good seal or does it allow a constant steam leak? And/or anything else on the boiler showing a water-trace line that may have been or still be leaking even just a little steam?

Jtr71 (original poster)

#3: Post by Jtr71 (original poster) »

I actually had a bad pressure stat for a long time and the machine kept overheating and setting off the pressure relief valve and steamed everything. It was bad for like 6 months and just started acting up again so I'm guessing that's what started the problem

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cafeIKE
Supporter ❤

#4: Post by cafeIKE »

IMO, the water ingress likely preceded the insulation failure. When the connections corrode, the resistance and hence temperatures rise at double the rate of the resistance increase. I=V/R and P = 1²R.

If self-repairing, get proper insulated terminals, a proper crimper and replace items to which the wires connect if they are also corroded.


Jtr71 (original poster)

#5: Post by Jtr71 (original poster) »

I actually replaced one wire in the past I'm just not sure how to replace this because the last wire I did was two connectors like your picture. This is the outlet plug feeding into two wires with connectors and one ground. I'm not sure where I can find that wiring assembly.

JRising
Team HB

#6: Post by JRising »

Oh. How happy would you be if your plug was 8 to 12 inches shorter? I didn't notice that it was your power-cord until you mentioned it. You could probably get away with cutting off 6 to 8 inches of the damaged conductors and crimping on the new connectors, you can get them from whatever hobby stores have sprung up since the demise of Radio Shack in your area.
Or, take it to any place that repairs any appliances, they'll be able to repair or replace your power cord. If you don't already have a crimping tool and a big box of assorted crimp-terminals, ask your hobbyist friends if they want to earn a beer helping you put new ends on the power-cord. It's barely a half-hour job and that includes the time it takes to drink the beer.
My quick search of Digikey Canada's power-cords didn't reveal anything with the insulated push-on fittings already attached.
https://www.digikey.ca/en/products/deta ... -R/8597827
If you want to try searching Digikey in the U.S. remember that "Connector A" has to be a "NEMA 6-15", that's the end going to a North-American outlet, and then scroll through seeing what's available... But your cord is probably okay except for the last 8 inches.

Jtr71 (original poster)

#7: Post by Jtr71 (original poster) »

Thank you! I'm probably going to cut it when I get home and connect it cause I have no idea what cord to order and I have no experience wiring stuff lol if I can't find it on YouTube I'm out haha