Doug580l
Senior Member
Yes, the door and windows are closed.I read through this thread last night and had to let it stew a bit on the burning inside my head. I do have a couple of questions and observations based on what little I've had to do for operator complaints about air conditioning. I'll play the levels advocate here for a minute or two.
My first question is do you shut the door and all the windows while running the AC? Do you have it recirculating the air inside the cab. The reason I bring it up is because you keep getting water being blown out the vents. Water would be a normal occurrence in a humid and hot climate because cooling the air would drop the water out. Cool air won't hold as much water. But if you are recirculating the air in the cab, the air will get dryer over time and the water will go away. We had tremendous complaints about AC when the weather would warm up in this area. The reason would be obvious when we drove out and saw the machine from half a mile away. The front window and door was open along with the side window. The cab filters would be found to be plugged and the air mix door was stuck. The training for the operator was that fact that the AC unit only had the capacity to cool the cab, and not whole outdoors. Basically they had a choice, close things up or forget about the AC.
I also keep seeing a reference to a TXV or what is known as a thermal expansion valve. I worked quite a bit with those kinds of valves when I was in the navy. We had huge chill water units and a couple of big freezers that used them. When I got out and started working with auto and equipment units like Red Dots and such, I found out that they didn't use TXVs. All they had was an orifice and the switching worked purely on pressure.
I don't mean to be blunt but if I were the service manager and it was found that the compressor is working properly, the pressures are at specification, the evaporator and condensers are clean and the receiver dryer wasn't plugged, then there is nothing wrong with the system. The more likely issue is the interpretation of how the system is supposed to work. Interpretations and opinions are not a warranty issue.
As far as the air recirculating, there is no switch for that but there is foam panel on the hvac side cover.
This machine does use and expansion valve and they say that they checked it and it's working properly.
If you go by the service manual, the vent temps and the compressor pressure is not within specs. In the videos I sent the link to the vent temp is about 55 at around 86 degrees outside. Specs are 36 to 53. I haven't checked the compressor pressures since I got it back this time but after the first service it was about 20 on the low side and 165 on the high side and the vents were at 60 degrees. After the second service at 98 degrees out, humid and running for over 30 minutes at full throttle the low averaged about 24 and the high 200. The pressures were better for the first few minutes, L-29 and H-225, that's probably what the dealer is going by. The service manual says that between 86 and 101 degrees the Low should be 15-33 and the High 210-265.
There are times when the vent temps have gotten down to around 50, but they also seem to fluctuate at times between 50 and 58 or so.
The vents didn't leak any water until after the second service. There is a lot more water now after the 3rd service.
As far as I know, all they have done for service is hook it up to a machine and remove and put the freon back in. They also removed 1 drain valve on the second service and another one on the third service. I think they added dye to the system to check for leaks on the 2nd service.