Yes, agreed to all the comments about heat drying, etc. for electronic
assemblies.
I have had fairly good success with flood recoveries by removing as much of the
cabinetry as possible, removing any tubes, and IC chips and components that are
socketed, spraying out the "guts", sockets, etc. with fresh spray water to
remove silt and flood water sand, grit, etc.
If panel meters and their movements are involved, they will have to be
disassembled and cleaned independently.
Remove as much plastic as possible (cabinet parts, dial indicators, knobs,
etc.) for the follow up baking process.
After fresh water spray cleaning as much as possible, move quickly to remove as
much standing water by using an air compressor. If you are lucky to have a tank
of Nitrogen Gas, this is even better to evaporate moisture quickly in tight
areas.
Then the oven bake (120-140 degrees) to evaporate remaining water in areas not
previously removed by compressed air (coils, transformers, etc.). After about
40 minutes in the oven, remove unit and again spray with compressed air to
removed beaded up water in areas. If you are timid about the oven you can still
use a high quality hair dryer, although it won't be as effective in beading up
water.
The key to recovery is to remove all moisture pockets before any component with
a tin plated steel lead (resistors, caps, coils, ICs, almost any soldered
component with part of the lead exposed) has a chance to begin the oxidation
(RUST) process. As soon as possible after moisture removal, take a can of
Potentiometer Cleaner-Lube and spray into all openings of Pots, rotary
switches, etc. to lubricate and displace any remaining moisture.
DO NOT leave unit standing around in natural air for very long (definitely not
a week) because the rust process will begin quickly. Once rust begins, it is
just a matter of time before individual components begin to fail. That's when
your problems begin and the electronic unit may then be considered scrap.
Ron
WW8RR
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