Jeff - There are many guys here at XS who run that MCP 355 and claim great results. I, on the other hand have owned 5 of the higher powered DDC 3.2 18w or MCP 3.25 18W pumps and 3 out of 5 have failed. After finally tracing the circuit board last week, I consider the design flawed. The reason on the 355 and 3.25 is that there are two cheap capacitors (from Lin Wuan in China I believe) that are easily effected by either water leaking in from the top, or the strength of the magnetic field generated by the coils. Simply put, on the less expensive MCP 350 (which has a much safer reliability record over many tens of thousands of owners), the strength of the magnetic field, along with the lower current, mean that the cheap Chinese caps dont operate near their limits, as they do on the MCP 355 and MCP 3.25. And in turn, that means, your chance for a melt down, LOL (well, you have seen it, ....literally, ... so you know I am not $hitting you) is much less. The 355s and the 3.25s need to be re-engineered so the space between the PCB and the coil is about 19 mm (this is a result of the Maxwell derivative for field strength affecting charge), and the $hitty Chinese caps need to be upgraded to decent higher charge Japanese caps.

You need to talk to Debbie at Danger Den to get an RMA, and when you do, ask for a MCP 350 replacement.