Opened up my machine today, to do a descale, and found this:


The lead to the heating element looks cooked! Two black wires from this lead, looks like one goes to the power switch and the other to the electronics / controller box.

The machine seems to have been working fine- pulling normal temps and pressures. One reason I wanted to descale, is that my hot water tap has never really worked right (very low output). I know low water levels can cause this, I'm wondering if that could also be related to the cooked lead (too much heat).

Any thoughts on what I should do about this?

Thanks for the help, as always!

That melt can be caused by high resistance in the terminal connector (corrosion, loose connection, etc.).

When you say that the hot water tap has low output- do you mean pressure or volume?
Low pressure could be an obstruction anywhere in the hot water line all the way from the boiler to the spout. It could also be low pressure in the boiler. If the pressurestat is set low for better espresso temperature it will affect the pressure which is used to dispense not only the steam but hot water as well. Scale can also cause problems.

One suggestion; when you get this cleaned up use a good quality female quick-connect for the repair. This connection has a lot of current through it so any looseness will result in lots of heat as the picture shows. Don't have a figure for you but the new female terminal should take a good push to slip on and it wouldn't hurt to re-examine this after the repair +5 or 10 operating hours for signs of overheating.
KDM

Good advice from duke-one. DO not use an aluminum connector. Find a heavy-duty brass one. The ones found in most chain auto parts stores are nut sufficient for the task. Go to an electical supply store (not Radio Shack). A high end automotive sound installer might have them as they ar used on high wattage sound systems.

Thanks all. After adding decalcifier/descaler to the boiler and powering the machine up, I saw a spark at that particular connection when the heating element came on. So I'm guessing that particular connection was loose or corroded- I'll replace.

I'm still perplexed by my hot water tap. The feed comes from the bottom of one side of the boiler.... I pulled the water probe out a good 3/4", but still get only 1-2oz of hot water from the hot water tap, after that it's just steam and drips. It doesn't seem clogged, just behaves as if the water level is low, no matter how far out I pull the probe. By the way, I pulled the probe completely out to check and it was free of scale. The boiler is running at 1.1 bar, and the grouphead is at 210 (erics thermometer). Everything else seems fine.

Maybe this is normal?

Another observation- now that my water level probe is pulled out 3/4", I'm also getting 1-2oz HW through the steam wand when I first open it up, then steam. Makes sense, but obviously I'll need to set the water level lower so the steam wand behaves as it should.

I don't understand how I'm getting so much steam through the HW wand, when the feed is at the very bottom corner of the boiler. Is there possibly a "stand pipe" or something inside the boiler for the HW feed?

By the way, this is an Isomac Millenium.
Thanks for the tips on the HD brass connector- will find one tomorrow.

On the Faston-style terminals, the higher quality ones are often brass (or bronze) and then tin (or nickel) plated.

I think you have a restriction at the boiler & when you open the water wand you get the water that's in the connecting tubing forced out and the rest flashes off to steam as it passes through the restriction from 1.2 bar dropping to atmospheric pressure.

I ended up taking the whole hot water feed line apart, including the valve. The elbow coming off the boiler was filled with soft crud, which was too thick to pass on through the copper plumbing line. The valve was also feeling pretty gritty. Disassembly of the whole thing took maybe 10-15 minutes and I'm now getting PLENTY of hot water off the tap- I've gone from 4oz in 15 minutes to 4oz in :10.

I also crimped the bad eletrical lead, which seems to have elmininated the sparking & shorting, but I'll replace the connection completely tomorrow.

Thanks to the tips and second opinions!