It's fairly obvious your HVAC tech did not use any diagnostic procedure to
triage your furnace. Contact a reliable CARRIER dealer and try again. This
time, tell the tech the fan won't shut down.
Several possibilities, probably the most likely one is that you have
no idea what you're doing. Keep at it until you've fried everything
in the unit, then call Some Guy back out and blame it on him. Sue him
for a new furnace.
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