It's just a guess without more data but perhaps the core has frozen over and air can't pass through it after running for 45 minutes. The fan continues running and the air that should be passing through the core is forced through cracks/leaks in the the heater box. A qualified AC technician can check the unit (particularly the expansion valve) to determine if it is freezing up.
Dunes!:)
The term of being high is being blown
by being blown
They won't so long as the air is being blown, but if it abruptly stops, air mass carried away by inertia will pull some more air behind it, a rarefication will be created between the two objects for a moment - sort of vacuum - and only this latter may pull the objects together - for a moment.
Dunes.
most often blown meaning supercharged - air being forced into the engine by a belt driven device..look on howstuffworks.com for a bunch of info. or it could also be referring to an engine that has "blown up" - blown a piston or rod etc.
The sentence "trees were being blown over by the wind" is in passive voice because the subject (trees) is receiving the action (being blown over) rather than performing the action.
You can be knocked down but not blown backwards.
Root
Blue smoke out the tailpipe--lots of it. If its a blown ring seal, then the oil is being "blown" into the air cleaner, burned up and out the exhaust. Also, the engine oil level will be next to nothing.
A photograph.
yes