2010 forester blowing hot air only even with AC button on . Thought it might be low level issue with refrigerant. When I hooked the kit up with the can and gauge the system was a little low but wouldn't accept any of the can. Not a drop. Is something stuck closed?? I tested the kit on another car and it worked, I guess that rules out a problem with the kit . HELP!

Is the compressor hub turning? It may not take any refrigerant if the compressor isn't running.

 

If the compressor is turning, quickly touch the lines coming off the top of the compressor. One will be very hot, the other should be cold. If it's humid out you should see condensation forming on the outside of the cold line.

If both are hot, there is likely a charge issue.

If the line is cold like its supposed to be, the problem may be with the blend door actuator or the control head in the dash.

When I start the car with everything off, then hit the ac button, I can hear something engaging. Then if I hit the button to "off" then back to "on" , I can hear it engaging again. You mentioned both lines being hot , and the sure are hot , one a little less than the other . Like I said when I tried to charge it , it wouldn't take a drop. No condensation on lines at all. Like there was a blockage or something .

You may just be hearing the radiator fans turn on, which is what they should do when the AC is On. But that doesn't mean the compressor is turning. If there is a cover over the compressor, remove it so you can see the hub and be sure that the compressor is actually turning when the AC is switched on.

 

If the compressor is running, the charge is probably just low. Try hooking up the can again, but be sure the quick connect engages the fitting all the way. They can be tricky sometimes and not seat all the way.

I believe the owner manual tells you that under heavy loads computer turns the AC off.

 

Could it be your issue?

If your refrigerant is really low the AC compressor won't come on. This is one thing on the car you may want to take to a shop to get leak tested and serviced. Those cans suck as far as gauges and you need a proper gauge set.