it's been that warm in my shed, anotherpy with no issues with the equipment at all..if it's 85 plus outside, i don't run my heater any warm..don't need to but think about it being 83 and my heater will run to maintain my 85. it feels about as hot as standing in the sun on an 90 degree day. i've worked in the shed when it's that hot with stuff running and while hot, it's not so hot that i can't stand it, if you know what i mean.(and i'm not a fan of weather over about 85 the way my wife is) i did nothing special to ventilate the pump motor..the only things i did were:

-put the double plastic vents according to spec for fresh air intake to the heater which is required by codes in canada. i would say they are 1.5 times the required square footage needed for proper intake. i was going to put one but it was so easy to do, i thought better safe than sorry.

-whirlybird- i was prepared to buy a powered whirly bird if necessary. i haven't needed it but if i did, easy to swap in. fyi, i have a powered whirly bird in the roof of my house..it's amazing how much heat it removes. unbearably stifling hot in the attic on an 85 degree day if it isn't running. comparably, the shed is nowhere near to being that hot..just comfortably hot. i do get a bit of shade from some mature trees all around it, but the face of the shed you see gets a lot of sun for half the day with no protection. i really think the key is the height of the shed. the shed dimensions by the way are 8 x 10 and i believe it's 10 ft to the peak. i put in double 120 watt bubbles for lighting which is not super bright given the height of the shed but bright enough to work in. i intentionally redid my plumbing to give the pump breathing room from the heater and the filter. the original pump was kind of squeezed between the 2. the way the pump is now plumbed, i have it set back so that the end connected to plumbing sits about 6 inches back from the edge of the heater i think and there's about a foot clearance all around. i'll take a few more pics so you can see more specifically how i've got that stuff arranged and post shortly.

-and so you know, i have no end air vents at all..again, was something i could have considered doing but wasn't necessary.