"Hey, kids, fancy some legionnaires' disease?"
In actual fact, that'd be perfectly safe. Don't know about anything else living in the water though. Anyways, wer'e talking about condensate from a compressor aircon here, aren't we - Out of the cooled air, into the bucket, not a cooling tower for an evaporative cooler?
Leigonella ingested is harmless. It's only dangerous when it's breathed in as an aerosol. - like the fine spray from a shower rose. It multiplies rapidly in warm water.
I gather that before we knew exactly what it was and exactly how to test for it the standard test was to sniff the culture in the Petri disk. Apparently it has a characteristic odour.
The beast can survive in water up to near 60 degrees C, which is why the greenie advice to turn your water cylinder stat down to 50 or 55 degrees to save energy was quietly dropped. (AFAIK no one from the greenie camp publicised that they'd dropped another Bo**ock, so there's probably lots of water cylinders running dangerously cool.)
My worry is that many condensing boiler flues can run way below 60 degrees, and if the system is not used to generate stored hot water, or the boiler stat’s wrong, or the system is a combi with hot water on demand set to well below 60 degrees (which should be safe, since any legionella in the cold main doesn’t get stored at nice cosy breeding temperatures) that flue could never get to sterilising temperatures.
The water produced when methane or propane burns, which you see as a plume of condensed water droplets from the flue of a condensing boiler, "has a ph similar to tomato juice" and has strict disposal rules - you aren't supposed to run it untreated to a fresh water drain, feed it into a cast iron system that does not have other water regularly running through it or let it contact concrete or brickwork. (The condensate can dissolve more than half an inch of mortar / pointing in a year.)
I wonder what ph is necessary to kill leigonella, and whether the bug can evolve to cope.
I've asked the question at training and assessment courses but never had a satisfactory answer. Sand, meet head.