Proven Again - H2O & Electrons Don't Mix

[markpj23]

As a network guy I always try to determine root cause of a problem, lest it come back to haunt me later in life. Y'all may have seen my smoke-tested A/C unit controller in another thread.

Now for Root Cause:
When we got back to the boat I noticed that the broker had shut down nearly all of the 12V switches on the panel. Didn't think much of it as I fired things up again. I also confirmed that the FWD A/C was tripping the breaker immediately, as he had told me.

Ran through my standard checks - bilge pumps working, no water where it shouldn't be etc. Switched on the shower drain sumps and the FWD pump ran for a bit longer than normal. Didn't think much of it.

Next day I started to tackle the FWD A/C unit problem. Visual inspection seemed normal. That's when I started my successful smoke test of the logic board.

Yesterday as I removed the old unit, I noticed the rusty bath tub ring around it. Hmm, dry under the berth where it is, no issue there. Then it hit me.... The condensate drain is routed to the FWD shower sump - which had of course been switched off.

The logic board is mounted outside of the drain pan, but the compressor wiring lays in the pan and is probably the reason for all the smoke. I won't know for sure until I can bench test it during the refurb. It did run (apparently) normally just prior to the smoke coming out.

Lesson Learned: Running the condensate drain to the shower sump IS a good idea. BUT you should have an "overflow" exit hole at the right level in the pan so that water can spillover into the bilge as a last resort. A wet bilge is less expensive than a wet A/C unit.....

[Lancerbye]

Too bad about your A/C , However H2O is not the problem because pure distilled H2O does not conduct electricity well. The conductivity increases as the mineral content increases. So blame the bloody salt. It works for me. Plus all the other trace elemts found in water.

[hellosailor]

Can't blame the salt. You can stick wires in salt piles all day long, and without the water there's no problem.<G>