Mine has a filter screen as well, but all kinds of "crap" gets through anyhow. The most annoying are little pieces of plastic film that go through and clog the exit holes of the top/bottom rotating sprayers. Can't complain though - its going on 14-15 years and still does the job as long as it gets a routine clean-out.
@jmillion: Yes, like the "warm hidey-holes" in my swimming pool pump motor! The thing is black, of course, sitting in the sun, and close to the ground. It started making an awful racket, so I brought it down to my workshop to see if I could fix it. I hadn't gotten much more than the back cover off when out comes an 8-inch long garter snake! Boy, did I jump! Fortunately, all I screamed was "AHHH!" and it only took a moment to grab "Gregory" (as my son has since named "him") with a pair of pliers, run upstairs, and deposit him in the woods.
I put a piece of vectorboard over the vent holes after that.
Squirrels seem to love to chew on vinyl. They've gnawed through a heavy vinyl birdseed container. Far worse was when they gnawed the insulation from the low-voltage wiring to my heat pump, causing continuous compressor start-stop cycling. The compressor wasn't designed for that and failed, necessitating replacement of the entire unit, costing a few thousand dollars.
Needless to say, the current unit has the low-voltage wiring run inside steel-jacketed "Greenfield" tubing.
Good comments, John. Kudos for attributing "debug" properly to Grace Hopper.
My company makes electronic equipment for use throughout the world. The gear used particularly in the more tropical climates is often assailed by various and sundry "vermin". It's often a design consideration; water ingress is one thing, but is it vermin-proof? Ha! Maybe the most unusual incident occurred when we brought a pallet of gear into the factory for rework from the field. A lady opened up the housing of one unit to find a 6" long snake! True, it was dessicated and no threat, but still quite shocking (pun intended). Critters always seem to seek out warm hidey-holes.
I know this is a little off topic, but I heard a story of a grizzly bear getting into a high voltage power line. The story turns out to be true and with a little surfing you can find pictures of a grizzly bear that dug up a high voltage power line. I always wondered if the hum made him think the cable was somehow linked to a bee hive.
Another interesting critter is the ant. When I lived "out in the country", ants swarmed the contactor on my air conditioning unit, rendering it useless. Also got into the telephone junction box outside and disrupted it, too.
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