Upon arrival I found that the system was incorrectly wired. Gave customer estimate so I have system wired correctly and he agreed to have work done at this time. Replace thermostat wiring and fuse and found that the thermostat had failed causing it to kick the fan on and pop the fuse bleeding 14 V to the fan terminal. Recommended replacing thermostat customer wanted to do it on his ownthanks for having me out today, Eli