tracking down A/C problem

knucklehead27

Member
Joined
Jan 14, 2011
Messages
50
Reaction score
0
Points
6
01 GMC Sierra 5.3L. Low pressure line gets beer can frosty but does not blow cold. any initial thoughts????
 
Throw a set of AC gages on it and let us know what the pressures are. With engine off both the high and low pressure gages should read about 170#. With the engine running and the AC on at idle you should have about 35-40# on the low pressure gage. Whit that pressure and if it 80* outside you should have duct temps around 40-45*.
 
Throw a set of AC gages on it and let us know what the pressures are. With engine off both the high and low pressure gages should read about 170#. With the engine running and the AC on at idle you should have about 35-40# on the low pressure gage. Whit that pressure and if it 80* outside you should have duct temps around 40-45*.

well what you said is not really true. you don't know what the ambiant air temp is or do you know how much free on is in the system and you don't know if the motors hot or cold. All these factor in as to how much pressure is in a None running ac system. Now most of the time a cold motor and a working ac system will have UNDER 100 psi with engine off.

Then when running a correctly working ac system will have 25 to 45 psi on the low side and 190 to 225 psi on the high side.

now knuckle head you say beer can frosty is the line freezing up? Over charged?

When was the last time the ac was serviced? What was done?

Can you tell us what the pressures are?
 


Back
Top