My heater wire has burned up twice. I trimmed the wire, cleaned it up the first time. Couple of months later, bam, burned again. I haven't touched it in about 6 weeks so the corrosion is starting to build on it a bit. What is causing this? A bad connection? Faulty wiring? How can I go about fixing it?

It worked fine for 2+ years and now seems to have trouble.

Here's what I have. If more info is needed, let me know.

Hydro-Quip ES-1001 Heater (or HQ-1001E?)
Model # RLFJA2C-AKB0G0R
220V elec heat

After looking at that picture, I would say you need to seriously REPLACE that buss strip. That corosion can not be cleaned enough to prevent an increase in resistance, and thus heat, which is causing your failure. I see situations like this many times in my field.

Charger you have a lot of good advice to give here. I appreciate your contributions to the board.

In the field normally what I do is just cut off the burned ends of the wires, (eliminating the strip altogether) and then use a big wire nut to connect the them back.

Wire nuts are cheap too!

This is a classic example of a situation where the connection is at fault, and not the spa equipment. It happens ALL THE TIME, and so many techs and people look to accuse the equipment first.

There's a lot of other examples of 'bad connections' here:
http://spasupport.com/electrical/main/burnedwires.html

This topic is moved to top of the line.

This also happened to mine. The others are correct about replacing the terminal strip. Mine was like yours in it had rivets holding the different layers together. In my case, I believe over time they loosened and caused the overheating as you are seeing. I did not replace the terminal strip with another, I installed a distribution block, which is much more robust, allows for more terminations, and it uses a hex wrench to tighten wires, not a slotted screw. But I also had a problem exactly like yours in the disconnect, where water corroded one of the lines and again resulted in a melt down.

I just went throught the burnt wire syndrome over the weekend. I noticed tha the tub temp had dropped off and when I got around to checking it, I found a heater wire had burnt through. The wire had also melted through my light air switch tube which explained why my light had been getting harder to switch on. I had some 10AWG braided wire lying around, so I cut wire for both sides of the heater element, got some crimp terminals and crimped them on. then I soldered the terminals to prevent future oxidation. I installed the wires and then liberally coated the connections with vaseline, also to prevent future oxidation. I'm back in business.

I have a similar situation I am dealing with, but the heater wires are bunt at the relay switch's. It looks like water entered the control box and arc'd and melted the wires. I'm thinking that new wires, and relay's will fix the problem. Any other suggestions?

Without photos, one can only take a guess.