A/C blowing hot air

Tiny
KELLY030
  • MEMBER
  • 2005 NISSAN ALTIMA
  • 160,000 MILES
My freon is full but when I turn my a/c on it blows warm air. Then it may kick on to cold after a while, then kick back to warm. Someone told me it sounds like it is short cycling. What do I need to check and replace? I have already replace the low pressure valve.
Tuesday, April 30th, 2013 AT 12:44 PM

6 Replies

Tiny
KHLOW2008
  • MECHANIC
  • 41,814 POSTS
This sounds like a classic compressor clutch problem. Here are a guide to help you confirm the problem.

https://www.2carpros.com/articles/car-air-conditioner-not-working-or-is-weak

and if so

https://www.2carpros.com/articles/replace-air-conditioner-compressor

Please let us know what happens.

Cheers,
Was this
answer
helpful?
Yes
No
+2
Tuesday, May 25th, 2021 AT 11:28 AM
Tiny
KELLY030
  • MEMBER
  • 2 POSTS
The a/c compressor is disengaging, and it is not switching to heat. Thanks for the guide I tested for power at the compressor and there was. Then replaced the compressor and it is all fixed, I love this site!
Was this
answer
helpful?
Yes
No
+4
Tuesday, May 25th, 2021 AT 11:28 AM
Tiny
BOULDER40MMA
  • MEMBER
  • 2 POSTS
I am having this issue with my wife’s 2006 Nissan Altima. 2.5liter. The compressor clutch is engaging and it shows it has Freon. The valve shows red and the can says that means there’s an issue. It won’t take any Freon and it’s not freezing up. It worked for her in the morning then she left after a couple of hours and it only blew hot air. Is there any fuses I should check?
Was this
answer
helpful?
Yes
No
Tuesday, May 25th, 2021 AT 11:28 AM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 51,628 POSTS
The clutch is turning on can you tell? Here is a guide to help you see if the clutch is turning on:

https://www.2carpros.com/articles/car-air-conditioner-not-working-or-is-weak

Please run down this guide and report back.
Was this
answer
helpful?
Yes
No
Tuesday, May 25th, 2021 AT 11:28 AM
Tiny
BOULDER40MMA
  • MEMBER
  • 2 POSTS
My clutch is spinning and engaging.
Was this
answer
helpful?
Yes
No
Tuesday, May 25th, 2021 AT 11:28 AM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 51,628 POSTS
Okay, now we need the high side pressure reading when the system is running. here is a guide to help you see how the system should be working:

https://www.2carpros.com/articles/re-charge-an-air-conditioner-system

High side should be about 235 psi.
Was this
answer
helpful?
Yes
No
Tuesday, May 25th, 2021 AT 11:28 AM

Please login or register to post a reply.

Related Air Conditioner Blows Hot Content

VIEW MORE