Cadillac Owners Forum banner

21 - 35 of 35 Posts

·
2002 Deville
Joined
·
16 Posts
Discussion Starter #21
I felt the ac lines going through the firewall and one was very cold, the other was only very slightly cool.
If I need gauges, is there a place with decent prices for decent quality that you know of?
 

·
Master of the Dark Art of Diagnostics
2003 DHS - two-2002 DHS, 2003 SLS, 1995 Sedan DeVille, 1989 Coupe DeVille
Joined
·
19,509 Posts
I felt the ac lines going through the firewall and one was very cold, the other was only very slightly cool.
If I need gauges, is there a place with decent prices for decent quality that you know of?
==========================
If I need gauges, is there a place with decent prices for decent quality that you know of?
ABSOLUTELY!
MOUNTAIN 8205 gauge set - $39 - with free shipping -

you'll also need a can tap - to dispense freon - $5.50 -

and possibly some 134a freon -
 

·
2002 Deville
Joined
·
16 Posts
Discussion Starter #25
Regarding the two ac lines going through the firewall. What does that reveal if one line is cold and the other isn't?
 

·
Registered
2000 Deville Base, 2019 Corvette Grand Sport
Joined
·
1,037 Posts
It reveals that you are low on refrigerant.
Being that the op is going thru all this stuff with still no resolution, me personally I would start from scratch and go for $25 bucks and be sure. Empty what you put in the system so far by pushing in the schrader valve until the system has nothing coming out and zero pressure. Go buy 3 cans of freon (12oz each) and put them in. You only can get out of each can about 10.5-11.00 ozs. That would put you very close to the system capacity of 35.2 ozs. That would give you a great idea of how your system is performing with the correct amount of freon. This is a relatively archaic way of filling the car with the correct amount of freon but it is effective for diagnostic purposes and it's cheap.
 

·
2002 Deville
Joined
·
16 Posts
Discussion Starter #28
Well, I ordered a set of gauges from Amazon and will check the pressures on high side and low side. Should be more accurate than the gauge on the can of refrigerant that I used.
They'll be here in a few days. I'll update when I have more info. Probably Friday.

Appreciate all the input.
 

·
Super Moderator
White Diamond '03 DHS (with DTS floor shift)
Joined
·
86,975 Posts
One word of caution with the gauges. You will have two red and blue valves. One each on the manifold and one each one the end of the hoses. NEVER open the red high side valve on the manifold unless you are pulling a vacuum. Opening it will open the can to the high pressure side of the system. As you can see from the table that Sefiro posted, you could be putting 200 psi into the can . I don't know what the can bursting point is, but I wouldn't want to be holding it or be near it with that kind of pressure in it. Read up and watch some videos before recharging the system.
 

·
Master of the Dark Art of Diagnostics
2003 DHS - two-2002 DHS, 2003 SLS, 1995 Sedan DeVille, 1989 Coupe DeVille
Joined
·
19,509 Posts
One word of caution with the gauges. You will have two red and blue valves. One each on the manifold and one each one the end of the hoses. NEVER open the red high side valve on the manifold unless you are pulling a vacuum. Opening it will open the can to the high pressure side of the system. As you can see from the table that Sefiro posted, you could be putting 200 psi into the can . I don't know what the can bursting point is, but I wouldn't want to be holding it or be near it with that kind of pressure in it. Read up and watch some videos before recharging the system.
==================
EXCELLENT POINT -
 

·
2002 Deville
Joined
·
16 Posts
Discussion Starter #31
One word of caution with the gauges. You will have two red and blue valves. One each on the manifold and one each one the end of the hoses. NEVER open the red high side valve on the manifold unless you are pulling a vacuum. Opening it will open the can to the high pressure side of the system. As you can see from the table that Sefiro posted, you could be putting 200 psi into the can . I don't know what the can bursting point is, but I wouldn't want to be holding it or be near it with that kind of pressure in it. Read up and watch some videos before recharging the system.
Makes sense. Appreciate the heads up!
 

·
2002 Deville
Joined
·
16 Posts
Discussion Starter #32
Well, I got my gauges and sure enough, the refrigerant was low.
I added r134a until the low side stabilized at around 37 psi and now the car cools nicely on both drivers side and passenger side.

There are a couple of minor concerns I have though;
The high side pressure is only at 125 to 130. I even tried adding some more refrigerant to see if it would go up, and it stayed at 125 to 130 so I bled it off again.
The other thing is, when I have the temp control set to auto, the ac compressor seems to run constantly, even when the temp is turned up all the way to 90f.
When I turn off the ac though, the compressor does stop running as it should.
 

·
Master of the Dark Art of Diagnostics
2003 DHS - two-2002 DHS, 2003 SLS, 1995 Sedan DeVille, 1989 Coupe DeVille
Joined
·
19,509 Posts
Well, I got my gauges and sure enough, the refrigerant was low.
I added r134a until the low side stabilized at around 37 psi and now the car cools nicely on both drivers side and passenger side.

There are a couple of minor concerns I have though;
The high side pressure is only at 125 to 130. I even tried adding some more refrigerant to see if it would go up, and it stayed at 125 to 130 so I bled it off again.
The other thing is, when I have the temp control set to auto, the ac compressor seems to run constantly, even when the temp is turned up all the way to 90f.
When I turn off the ac though, the compressor does stop running as it should.
======================
ac operating pressures - especially the high side - are directly related to ambient temperature -
the hotter it is - the higher the pressure -
 

·
Registered
92 Fleetwood 2dr cpe - FWD, 96 Seville SLS, 02 Seville
Joined
·
909 Posts
If you are in a dry environment, then your hi side measurements are fine.

If humid, then:
  • you might have water in the system. The moisture is displacing Freon and the compressor is not tuned for pumping moisture.
  • orifice is cracked blown other
  • compressor falling.
Try again when the ambient temps get high.
 
21 - 35 of 35 Posts
Top