On Friday, September 26, 2014 8:38:39 AM UTC-4, TimR wrote:
On Thursday, September 25, 2014 11:50:36 PM UTC-4, Cheryl wrote:



Guy opened the panel and the coils were rusted, and the water in the



condensation drain pan and circulating pipe was orangeish and was



clearly the reason why condensation wasn't draining and instead leaking



onto the floor.



Cheryl



This doesn't make sense. Coils are aluminum and won't rust. They have to be, they are wet all the time, that's how they work when cooling.



There should not be water in the condensate pan. It should be draining. But these clog all the time, partly because dust gets past the filters but mostly because biological stuff grows in dark moist conditions.



When the condensate pan clogs, and they all do eventually, you have to snake or blow the drain out - when it clogs, you still shouldn't get water on the floor. There is supposed to be a secondary pan that catches it. Then that pan is supposed to have a float switch that shuts off the air handler so you know you have to fix it.



There is no circulating pipe in this system, just a drain pipe. If there's water in the drain, it is clogged.

+1

There are probably some metal parts in there that can rust, but not the coils themselves. The box for example that holds the coils, maybe some brackets, etc.
And even if there is some rust, unless it's structurally compromised, I don't
see the compelling need to replace it. At least not for the customer....
These backup and leak water frequently, due to the drains getting clogged.
Clean the drain, and keep on trucking.....