No voltage to A/C compressor clutch
#21
OK, I put my gauges on the system and let it stabilize and the low readings indicated low charge to I added almost 2 cans and now readings are about 30psi low side and 275 high side. This was in 92 F deg. high humidity and squirrel cage fan in front of radiator. A/C blower on medium speed, temp. control on cold and the best temp reading I could get was 50 F deg. at center fascia outlet.
The system refrigerant capacity is 950g +/- 50g
Not sure if your system is the same but hope this helps.
Cheers,
Allan
#22
The "point" is that at 92 degrees out R134 at idle will produce a duct temp of about 50 degrees...which is what you have which is "normal". At "speed" the condensor can get rid of heat better and you'll get a duct temp of aroud 46 degrees or so which again is "normal" I think the point is you're thinking you can get it lower and I'm trying to tell you that you won't, recirc or no recirc there doesn't seem to be anything wrong. Try spraying some water over the condensor at idle and see if the duct temp doesn't come down a tad as if you were at speed. The OAT affects the gas/liquid because it is affected by it in the condensor outside of the cabin and its ability to get rid of built up heat....windows up, 92 out, 50 to 45 at the fascia is plenty cool enough...I just drove home in mine in NE Florida with an R134 conversion and mine was plenty cool inside and I'll bet the center duct temp was no lower the 48 at best.
#23
Bob,
My car was built 3/94. I'm very surprised that your car has the older control system. I thought they changed it in tandem with going to R134A refrigerant. Although it's not unusual for Jag to slowly roll out changes during a MY
The only other thing is to be careful how much refrigerant you put into the system, I know that if you have too much, cooling efficiency is deminished.
I live in NC so 92F temps and high humidity are not uncommon. My A/C works fine in normal (non-recirc) mode which I almost never use. However, as I mentioned above if I'm just idling or creeping in traffic for 20-30 mins or so the cooling system can't keep up. As soon as I start moving at normal speed normal service resumes.
One other thought is the receiver/dryer? Maybe the filter is blocked or the desiccant has lost some of it's effectiveness?
Cheers,
Allan
My car was built 3/94. I'm very surprised that your car has the older control system. I thought they changed it in tandem with going to R134A refrigerant. Although it's not unusual for Jag to slowly roll out changes during a MY
The only other thing is to be careful how much refrigerant you put into the system, I know that if you have too much, cooling efficiency is deminished.
I live in NC so 92F temps and high humidity are not uncommon. My A/C works fine in normal (non-recirc) mode which I almost never use. However, as I mentioned above if I'm just idling or creeping in traffic for 20-30 mins or so the cooling system can't keep up. As soon as I start moving at normal speed normal service resumes.
One other thought is the receiver/dryer? Maybe the filter is blocked or the desiccant has lost some of it's effectiveness?
Cheers,
Allan
I believe the '93 model year for XJS's was a big change for Jag......the first 6-litre engine and new body work on the windows, the 4-speed automatic with the V12's, etc. Was this the year they went to the A/C system that I have without the recirc. button? Did the previous years of 5.3 litre V12's have a recirc. button?
When they made the change in early "94 to the system you have, they must have done this resulting from complaints and poor cooling performance from cars without the recirc. button.
I checked in my Jag Parts microfiche and they do show both of the A/C control panels, the one for my type is listed as "Clarion E950"
Do you thiink it would be worth my time to write Jaguar asking them if there is a kit or some other fix for this problem?
Regarding your warning about over-charging the system, this would show up in the manifold gauge readings being too high and my readings are normal.
Thanks again Allan, you have given me a lot of helpful information for my problem.
Take care,
Bob
'94 XJS-V12
#24
1992 Major facelift, new body work, lights, windows. New instrument panel, new center console controls (trip computer/radio/AC) Only engine available in the US 5.3L V12 w/3spd auto.
1993 5.3L V12 dropped, 4.0L I6 introduced with 4 spd auto or 5 spd man. There were 100 of the XJR-S imported that had a special 6.0L V12 that is a different beast to yours but still had 3 spd auto box.
1994 6.0L V12 with 4 spd auto introduced. Rear brake discs moved to outboard, new a/c system with R134A refrigerant and (after VIN 190528) new control panel.
1995 AJ16 engine replaces AJ6
"Bob I just checked the pressure graphs in my manual and it shows the high side pressure should be between 200-250 PSI at 95F (bit less for 92F). For an evaporator temp of 50F the low side pressure should be about 45 PSI.
The system refrigerant capacity is 950g +/- 50g"
Cheers,
Allan
The following users liked this post:
Spillwaybob (07-29-2013)
#25
'94 XJS V12 Insufficient cooling from A/C in hot weather
Going to have to take a few days off.....I've had an equipment failure. When this is fixed, I'm going to evacuate and recharge the system with the exact amount specified and will record the manifold gauge readings.
Until then,
Take Care and thanks,
Bob
Until then,
Take Care and thanks,
Bob
#26
The "point" is that at 92 degrees out R134 at idle will produce a duct temp of about 50 degrees...which is what you have which is "normal". At "speed" the condensor can get rid of heat better and you'll get a duct temp of aroud 46 degrees or so which again is "normal" I think the point is you're thinking you can get it lower and I'm trying to tell you that you won't, recirc or no recirc there doesn't seem to be anything wrong. Try spraying some water over the condensor at idle and see if the duct temp doesn't come down a tad as if you were at speed. The OAT affects the gas/liquid because it is affected by it in the condensor outside of the cabin and its ability to get rid of built up heat....windows up, 92 out, 50 to 45 at the fascia is plenty cool enough...I just drove home in mine in NE Florida with an R134 conversion and mine was plenty cool inside and I'll bet the center duct temp was no lower the 48 at best.
Bob
#27
Allan,
Since you are the only one with a '94 with a recirc. button in this thread, when you get a chance would you do a little test for me. Measure the duct temp. with all other conditions being the same, in both outside air and recirc. modes Blower speed medium and temp. control at max. cold.. Don't expect any temp. changes right away, I think you should give
the unit at least 5 minutes to react. If possible, do the test at a hot time in the afternoon. I'm curious to see how much difference there is.
Thanks again for your help.
Bob
Since you are the only one with a '94 with a recirc. button in this thread, when you get a chance would you do a little test for me. Measure the duct temp. with all other conditions being the same, in both outside air and recirc. modes Blower speed medium and temp. control at max. cold.. Don't expect any temp. changes right away, I think you should give
the unit at least 5 minutes to react. If possible, do the test at a hot time in the afternoon. I'm curious to see how much difference there is.
Thanks again for your help.
Bob
#28
The following users liked this post:
Spillwaybob (07-30-2013)
#29
I never said "recirc" wouldn't change the duct temp, just that the duct temp you're getting is "normal" for r134 and your conditions. If you had recirc I would expect maybe a 2 degree drop in duct temp as your cooling already cooled air. The OAT will impact the duct temp based on its effect on the condenser so duct temps will change based on OAT recirc or no recirc. The "auto" mode IIRC will adjust between norm/recirc/heat/evap based on the cabin temp which is why the "recirc" button may not be present...IIRC it shifts things as it feels necessary too maintain the desired temp in the cabin.
#30
I never said "recirc" wouldn't change the duct temp, just that the duct temp you're getting is "normal" for r134 and your conditions. If you had recirc I would expect maybe a 2 degree drop in duct temp as your cooling already cooled air. The OAT will impact the duct temp based on its effect on the condenser so duct temps will change based on OAT recirc or no recirc. The "auto" mode IIRC will adjust between norm/recirc/heat/evap based on the cabin temp which is why the "recirc" button may not be present...IIRC it shifts things as it feels necessary too maintain the desired temp in the cabin.
Bob
#32
Bob, my 86 has no "recirc" switch but does switch between inside and outside air as deemed by heat vs cool and by the "auto" function. Some luxury cars don't carry a "recirc" function as too long in that constant operation will "stale" the air. Sounds like yours is up to snuff and will perform just fine. My 99 Explorer Limited had a "manual" "recirc max" or "auto" I ran it in "auto" and the blend doors and blowers would do as they needed between recirc, outside, evap or heat core to keep that temp, humidity at a constant level as selected by the temp knob.....similar to the Delanair in "auto"
#33
Ok Bob, I just got home and these are my findings.
When I left the house this morning it was 75F ambient and 67% rel humidity. On the highway after 30 mins of driving, I set cruise control at 75mph which on my car is 2500rpm. I set the climate control to manual, A/C on, fan speed position 2, face level slider at mid point and temp dial set at coldest (65F).
After 10 mins I measured the center duct temp and got a reading of 42.1F.
I then pressed the recirc button, waited another 10mins and got a reading of 40.4F
After lunch with ambient temp now at 86F and 56 rel humidity, I drove around town in typical stop/go fashion with speeds varying from 0-45mph. With recirc off I measured 48.6F and 46.4F with recirc on.
On the way home on the highway, still at 86F ambient and same conditions as before, I measured 45.2F without recirc and 44.1F with.
Just for giggles I increased fan speed to 3 and that improved non-recirc to 44.6F though the temp with recirc on stayed at 44.1F
At all times my auxiliary electric fan was off (it does not come on in my car unless coolant temps get above about 212F) which probably affected the ability of the system in stop/go traffic.
So it sounds as though your system is pretty much spot on, now I just need to go warm my toes up!!
Cheers,
Allan
When I left the house this morning it was 75F ambient and 67% rel humidity. On the highway after 30 mins of driving, I set cruise control at 75mph which on my car is 2500rpm. I set the climate control to manual, A/C on, fan speed position 2, face level slider at mid point and temp dial set at coldest (65F).
After 10 mins I measured the center duct temp and got a reading of 42.1F.
I then pressed the recirc button, waited another 10mins and got a reading of 40.4F
After lunch with ambient temp now at 86F and 56 rel humidity, I drove around town in typical stop/go fashion with speeds varying from 0-45mph. With recirc off I measured 48.6F and 46.4F with recirc on.
On the way home on the highway, still at 86F ambient and same conditions as before, I measured 45.2F without recirc and 44.1F with.
Just for giggles I increased fan speed to 3 and that improved non-recirc to 44.6F though the temp with recirc on stayed at 44.1F
At all times my auxiliary electric fan was off (it does not come on in my car unless coolant temps get above about 212F) which probably affected the ability of the system in stop/go traffic.
So it sounds as though your system is pretty much spot on, now I just need to go warm my toes up!!
Cheers,
Allan
#35
Fan speeds don't effect temperature for the most part except that they do provide some evaporative/expansion effect and therefore will drop it some but very little...little that a temp gauge will pick up but running the fan at low speed will provide better mositure removal which will make one feel more comfortable at a higher temperature once the temperature has stabilized (think how the low speed blower takes over in the auto mode once the high speed blower has stabilized/brought down the temp) also "wind chill" when blown over you will make one feel cooler by evaporating sweat at higher rate...it's why dogs hang out there tounge out a car window with their face exposed to the breeze!
#36
Allan,
You sure went to a lot of trouble to do the test and I really appreciate it. I thought the temp. difference between outside and recirc. would be more like 5-8 degrees but your figures don't lie. And yes, my system seems to be working normally. Some of my problem was I did not fully understand how my system works.....I was not aware that I had a recirc. mode which is chosen automatically by the ACECU according to what is needed to accomplish the driver's request. JTsmks was a big help in providing me with a detailed description of the system function. For this I thank the both of you.
This thread is well worn so let's put it to sleep.
Now I'll see if I can open another can of worms!!
Take Care,
Bob (Spillwaybob)
You sure went to a lot of trouble to do the test and I really appreciate it. I thought the temp. difference between outside and recirc. would be more like 5-8 degrees but your figures don't lie. And yes, my system seems to be working normally. Some of my problem was I did not fully understand how my system works.....I was not aware that I had a recirc. mode which is chosen automatically by the ACECU according to what is needed to accomplish the driver's request. JTsmks was a big help in providing me with a detailed description of the system function. For this I thank the both of you.
This thread is well worn so let's put it to sleep.
Now I'll see if I can open another can of worms!!
Take Care,
Bob (Spillwaybob)
#37
Fan speeds don't effect temperature for the most part except that they do provide some evaporative/expansion effect and therefore will drop it some but very little...little that a temp gauge will pick up but running the fan at low speed will provide better mositure removal which will make one feel more comfortable at a higher temperature once the temperature has stabilized (think how the low speed blower takes over in the auto mode once the high speed blower has stabilized/brought down the temp) also "wind chill" when blown over you will make one feel cooler by evaporating sweat at higher rate...it's why dogs hang out there tounge out a car window with their face exposed to the breeze!
See my reply (#36) to Allan.
Off Subject, why do your wiper blades park on the right side and mine park on the left??
All of these little subtle differences between 20 years of XJS production have yet to be discovered!
Bob
#38
#39
Hey all you A/C Sperts!
My A/C has been working fine, especially now that our ambients are below 90F and I learned how to use it.
BUT, yesterday a new wierd problem has occured. The system won't turn off with the blower switch in Off. The blower and Compressor clutch cycle rapidly----about every 3 seconds, the blower and the clutch click on just for a fraction of a second, a 3 second pause and then it repeats. Ignition switch in run position, engine on or off. Moving the blower switch to the other positions work fine as it should, the problem is only in OFF.
Anybody ever hear of this problem????
I need help again>
Bob (Spillwaybob)
My A/C has been working fine, especially now that our ambients are below 90F and I learned how to use it.
BUT, yesterday a new wierd problem has occured. The system won't turn off with the blower switch in Off. The blower and Compressor clutch cycle rapidly----about every 3 seconds, the blower and the clutch click on just for a fraction of a second, a 3 second pause and then it repeats. Ignition switch in run position, engine on or off. Moving the blower switch to the other positions work fine as it should, the problem is only in OFF.
Anybody ever hear of this problem????
I need help again>
Bob (Spillwaybob)
#40