You have to first diagnose and correctly identify the issue causing the problem before you can repair it. There are several reasons why AC systems can blow hot - to know how to repair it you need to know that reason.
it is a vacuum leak-replace the vacuum line from the right side along the right front-tiny vacuum line probably split
you have to by pass the heater core. get a 3/4 heater connection piece just one way trim your hoses down and then plug off your heater coe connections on your fie wall might try to take out fuse for blower motor if that dont work.you have to bypass heater core very simple thing
TRANSMISSION MODULATOR SEE IF IT BLOWS SMOKE OUT THE EXHAUST
May need a refrigerant charge Buy a kit at Wal-Mart or auto parts comes with instructions
Possibly needs recharged with refrigerant. You can check low pressure side with a guage.
the heater blows warm air when fan is on low but blows cold air when fan is turn to higher setting
A shorted wire in the console or the brake circuit. Does the car still have brake lights? If there are no children in your household then it is possible to defeat the lockmechanically.
where do I start? help? it is getting close to the cold season and I would like to repair my house before the wind blows.
AnswerReplace the blower resistor.
I have a 2006 Altima and it is doing the same thing.
that is bad... go get it checked up on!
check you thermostat for the temp setting