The other day I turned on my heater and I wasn't getting much out on the first 3 settings. On high, it came out normal? This was the same for my A/C. I thought a vacuum leak might cause this but couldn't find or hear one. I did have long tubes instaled last week if that helps???
replace your blower motor resistor, the thermal fuse is blown.
might want to check if the blower motor shows any signs of water entry, if so that'll cause the fuse to blow
He's not talking about the fuse inside the fuse panel but a resistor inside the motor itself. You will have to open up the motor cover and change the resistor inside it.