AC Blowing Hot With No DCCV Codes

[CMac455]

I'm having a problem with my AC not blowing cold. Whenever I last used it (which was last summer), the AC worked well. I had to change one of the thermistors in the center plenum in order to get the compressor to kick on.

The compressor is kicking on and I notice that there is a hissing in the dash whenever I turn the AC on. Otherwise the noise isn't there. I ran the self-diagnosis and I didn't get any codes.

Thank you for your help!

 

[joegr]

Is it blowing hot (heated) air?
If so, then it is almost certainly the DCCV. The self test only detects electrical problems. If the solenoid coils of the DCCV open or short out, the self test will catch that. If the solenoids are okay, but the valve is gunk'd up and stuck open, then the self test won't catch that, but the DCCV is still the problem.

Is the air just not cooled instead of heated?
If so, then your R-134a refrigerant level is low. If it's been correctly topped off in the last couple of years, then you have a leak that will need to be fixed. If no R-134a has been added in a few years, then it is just normal out-gassing and it just needs to be refilled. Note that the hissing sound you hear is the refrigerant flowing through the expansion valve. Normally, you don't hear this, but when the refrigerant level is low, you will hear the hissing sound.

 

[tireman]

Low refrigerant, recharge. +1 Joegr

 

[epikls]

My ac was blowing heated air also
I wasn't the dccv since I had just replaced it 4 days ago
My ac kicked on and off too frequently
I had air in the ac lines
Which I read online is had for an ac system
I took out the excess air and now my ac works great