Twice this summer my attic AC has shut off because the condensation pan has filled with water, triggering the emergency shutoff. The emergency shutoff is barely visible in the bottom center of the picture. So I figure my drain line must be clogged. Except that I can’t find the drain line! I’ve checked all four sides of the pan to look for a pipe leading out. Nothing. What you see in this picture is what I’ve got. Two pipes lead from the upper half of the furnace. One pipe leads away from the unit, the other extends down into the condensate pan. But I can’t find any pipe draining from the condensate pan. Shouldn’t there be one? Or is the water that collects in the pan supposed to evaporate and I’ve got a problem causing too much condensate? Had this furnace 6 years and this is the first summer we’ve experienced this.

Is an annual service on an HVAC air handler and condenser worthwhile? When I bought my home 5+ years ago, I was told the air handler is very simple, with only a few parts, so annual maintenance wasn't necessary. I've only had a service on the condenser once, when mice got in and chewed up wires. I change filters regularly, make certain the condensation line doesn't clog, and rodent-proofed the condenser. I have no issues but am wondering if an annual service would be beneficial. Thanks.