A fuse blows if it is drawing more amps then the fuse is rated to handle, or if there is a short. I suspect your fuel pump is starting to develop a problem, BUT DON'T USE A HIGHER RATED FUSE BECAUSE YOU CAN CAUSE AN ELECTRICAL FIRE !
the blend door is stuck open
A broken blower fan. Had that on my Ford Explorer. Not a big deal to have a mechanic fix it, under $200
low freon or none
Sounds like it is low on coolant.
cracked oil ring on piston
I know that my ( 1995 ) Ford Explorer has " a wide open throttle A/C relay " that shuts of the air conditioning compressor when I floor the gas pedal
Fuses blow when there is a short circuit or an over current condition.
The fluid can foam and cause slippage and/or blow out seals.
if its winter first check coolant lenvel and check coolant system for leaks. then check thermostat
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my 94 explorer wont blow heat
Has the engine ever been overheated ? That will do it !