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What are low on freon symptoms?

Avy2004

Full Member
Joined
Jun 10, 2006
Messages
37
Location
Aliso Viejo, CA
I went to the dealer today to have my A/C checked because it was not blowing cold enough. Service said it was working to specs and said I would have to service the A/C, which is not covered by warranty.
What exactly is servicing the A/C? Can my truck just be low on freon?
My A/C just doesn't blow cold enough. Even when moving on highways, it still doesn't get REALLY cold even after setting it on the coldest possible setting.
Has anyone had this similar problem and actually gotten it fixed?
 
If it is "working to specs" why would you have to have it serviced??? Didn't they put a pressure gauge on the system to test high and low pressure??? I'm not a hvac guru, but isn't that is how you test to see if it is low on freon?? ???
 
servicing a a/c system is a suck and refill, blowing out the condenser, connecting the gauges and checking outlet temp.  i bet it is low, gm spec's( i am a gm tech) are on the hot side if the max outlet temp spec is say 45 degrees most will run at 40 degrees for example. a general rule of thumb is 20 degrees off amb. temp.  i would get it serviced(should be about a hour, we charge 89.90 canadian for a service) and i bet it will be cooler for you.
 
a sign of low refrigerant could be the warm air you are experiencing, or constant engaging, and disengaging, of the compressor clutch.
 
rs72camaro said:
Check to make sure that you have it on recirculation and not on vent with the A/C.? ?:rolleyes:


  that too.  however, in "Auto" mode it cycles from "Recirculate" & "Vent" for some reason.  i would rather it did not.  my Trailblazer is the same way.
 
Freon is not consumed during use. If your system is low on freon then there is a leak in the system somewhere.

You can get an AC recharge for under $75 just about anywhere. But this will last only until the new freon escapes through the same hole in the system as the last freon.

Finding the leak and fixing it will likely be substantially more expensive.
 
PUNISHER said:
that too. however, in "Auto" mode it cycles from "Recirculate" & "Vent" for some reason. i would rather it did not. my Trailblazer is the same way.

Safety is the excuse.  Bringing fresh air in to the cabin to keep things safe and not stale.
 
PUNISHER said:
a sign of low refrigerant could be the warm air you are experiencing, or constant engaging, and disengaging, of the compressor clutch.

That was my answer.  It's the most obvious sign. 
 
DougD said:
Safety is the excuse.  Bringing fresh air in to the cabin to keep things safe and not stale.

I called the Volvo dealer because about a half hour after turning the car off, the hvac fan would mysteriously turn on and run at high speed.  As it turns out, that's on purpose to dry out the system to eliminate mold and that nasty smell.  Now that's a smart idea.
 
tclaremont said:
Freon is not consumed during use. If your system is low on freon then there is a leak in the system somewhere.

You can get an AC recharge for under $75 just about anywhere. But this will last only until the new freon escapes through the same hole in the system as the last freon.

Finding the leak and fixing it will likely be substantially more expensive.
good post...

AC systems are what we call closed loop.  that is where what is pumped is coming from the lines and not a tank...

Low freon symptoms..

Compressor does not click on.
Compressor cycles too fast....
Air is not cold.. but the above 2 are a better symptom...

If you are low you were low from the start, or have leak or someone messed with hose or fitting and allowed some freon to escape...

AC not blowing cold could be from other things too...
 
The seals tend to dry out especially over the winter when it's not used as much.  Sometimes adding refrigerant with sealer will help a small leak. 
 
Thanks for all the fast replies. The problem with my A/C is that it never really gets cold. This is my first GM car and I hope this isn't the coldest my A/C gets. My previous Expedition would freeze me out in 5-10 minutes with it on high.
I put it on recirculate, with both temps set to 60 (I have auto climate) and it still doesn't get that cold. Don't get me wrong, it does cool, but compared to other vehicles it is definitely lacking.
The service tech said that they measured the temp of the air coming out and said it was to specs. It was about 84 out and not that humid. I asked the service tech what the "spec" temp should be and he stated that with the weather like it is about 70. :E: He also said that if I wanted it colder, he would have to start by servicing the A/C. Kind of doesn't make sense because he just said it was working to specs.
I tried to explain how compared to other vehicles, my Avy is lacking. They responded by saying that you just cant compare vehicles and pointed out that my vehicle is black.
Oh well, time to go to another dealer.
I'll take it back to the dealer I bought it from (wasn't Chevy) and tell them to service my A/C since its still under a dealer 30 day warranty. Hopefully, that will resolve my problem.
Will keep everyone posted.
 
put thermometer in center dash vent...
drive on interstate at highway speeds..
put AC on coldest setting..

tell me what temp gage says for air coming out of main duct...

should be around 40-45 F in the duct...
 
Is there a problem when you're parked and after a few minutes the air starts blowing HOTTT?? Was in Mexico over the weekend and AC was a MUST down there, the rear view mirror temp was reading 125+ the entire time we were there.  Whenever we'd park within minutes we either had to bail from the truck since the air was hot or start driving around again. 

Yndio
 
ygmn,
I put a thermometer earlier in the morning outside temp was mid 70 and the coldest reading I got was 50. That was with passenger vents closed, recirc on, temp set to 60 on both. Tried it also on Auto as well as manually.
I will drive on the freeway later today and take another reading then. I will post the results later.
BTW, the service manager I spoke to insist that 20 under ambient temps are normal??
If that holds true, then in places such as Vegas, Arizona, and California deserts where the temps reach 120, 100 inside would be normal?
 
50 is not bad.. but not good either...

it is semi related to ambient but cannot say it is an absolute as it is a exponential...as there is a point where it cannot cool any more when cool out and high out...

ask him if it is 40 out I will get 20 degree air out of vents?? NO....


could be the heater core door not fully closing... or box is not sealing to firewall and letting in outside air.. this would mix more hot air with cool air and raise temp...

best? bet is to find a friend who is mechanic and have him check hi/lo pressures in system... to see if it is low...

if low.. then the question is where did it go or was it always low..

and when temp testing keep all front vents open to allow for maximum airflow across evaporator has this is part of the thermodynamic equation as well... when you close vents you create more head pressure for blower which reduces output air which reduces speed of air across evaporator which decreases cooling...

My suggestions..:
test on highway for mile or so... check temp..
have someone check pressures on high and low side (need to know ambient when this is done.) if it seems low...then do as KGT suggests and have it evacuated and put on vacuum pump to remove everything from system... then recharge to proper levels...

inspect hoses, compressor, dryer etc..for for dirt accumlating on an oil film...this would be signs of a leak

check belt to ensure it is at proper tension..

clean condensor and grill in front of bugs and debris.. heck run a hose on it to clear dust off as that reduces heat transfer greatly...

Drop lower duct work and clean out any debris that may have entered from outside like dead bugs leaves etc... (if you do not beleive it happens check the 2002 Cabin air filter thread....) this stuff blocks evaporator which again reduces heat transfer...

most you can do yourself except the evac and pressure test without proper equipment...

Ps...mine gets to 40 on highway when it is 95F & humid ....(2002 avy)

 
Edmunds.com Tech Center Air Conditioning


Above is a link to understanding how your AC works made easy

Insufficient Cool Air

Low refrigerant charge

Loose drive belt

Slipping compressor clutch

Clogged condenser

Clogged evaporator

Slow leak in system

Partially clogged filter or expansion valve

 
ygmn said:
Ps...mine gets to 40 on highway when it is 95F & humid ....(2002 avy)

After I just redid mine, I was seeing 30 degree air when the outside temp was reading 97.
 
OK, here are the readings I got:
1. When traveling on the freeway, all vents closed except drivers, recirc on, set at 60, the lowest I got was 48. Outside temp was 80.
2. While traveling in traffic, with all the same settings, the lowest I got was 54. Outside temp was 95.
While driving at a constant speed over 40, the A/C works fine, however, when driving on city streets the A/C temp seems to get warmer. Is this normal?
 
seems tad warm...

have level checked...
 
Hmmmm, My Av doesn't use Freon(r).

I would focus more on the fan/clutch & shrowd. It sounds as if you aren't moving sufficient cooling air through the condenser at the lower vehicle speeds.

On the flip side, does your HVAC fan and air movement remain steady? The pressure switch is set at a point to minimize ice-up conditions of the evap coil. It, and the HVAC fan need to be within the proper operating parameters or that icing-up condition can occur.

Ice-up:
Blockage/restriction of cabin air movement. (Do you have an 02 with the cabin air filter?)
Fan motor operation impaired?
Low pressure (compressor clutch) switch stuck on or set too low?
High humidity with the above conditions.
 
sperry said:
Hmmmm, My Av doesn't use Freon(r).
nitpicky.. hehehe

134 then...hehehe
 
`I just had to..

Lets see..
R134a
HFC134.... Whatever. :)

Boiling point -15?F yada yada...
 
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