If you're going to pour a small slab anyway, make it big enough that you can frame around the compressor to isolate it from the weather. IMHO if the manufacturer says to keep it out of the weather, it probably should be kept out of the weather. Also, before you fasten it to the floor, lay it on it's side and replace the draincock with an elbow & enough line to clear the bottom of the compressor then put the drain there. That is unless you like crawling around on the ground/floor to drain water off.
Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.
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