I have a 1995 ford escort lx the air conditioner does

You either have a clogged ac line or you have a vacuum problem that will prevent the correct vent doors to open to allow the air to enter

You need a new blower motor resistor (about $19.95). It goes in the blower motor housing under the passenger side dash. The resistor controls the motor speed, and will begin to work intermittently on certain positions, and then cease working altogether. I've had to replace them. Not hard.