320C Air Conditioning not cool

Our 320C has been giving us some issues with the air conditioning not blow cool enough. It always has kept us cool but now its not getting the job done. I wouldn't say its blowing warm just not as cool as normal. Also the digital ac control (where you turn the temp up and down on the control panel) reads 18.E instead of 18.0 on its coolest setting. I have done all the normal things like filters and condenser cleaning haven't seen any improvement. I am in no means a AC expert but know someone here is and would really appreciate some help. I have a feeling the 18.E has a clue as too what is going on but don't know what. Thanks.

Did you check the sight glass in the filter/drier to see if it has bubbles in the glass when the AC is on? Could just need a charge of 134A.

Second that....Same problem with e50 bobcat tony

Defiantly need to throw some gauges on the ac or have someone come out

E is indicating an active error code. To read the codes do the following;

Ignition on.

A/C controller power off.

Hold down both temperature switches for 3 seconds.

Scroll through the displayed codes using the temperature up and down switches.

A flashing error code means it is active. A steady error codes means it is logged.

If you have E51, that means low or high refrigerant pressure. If you have anything else, write it down and report back.

Good luck.

Thanks for jumping in here Cmark, I was hoping a Cat tech like you would chime in. :drinkup

CMark thanks for the response. I will be back at the job on Monday and will check out the codes. Thanks!

Cmark I just checked the error messages how you told me to. E51 and E45 are what came up. Both steady and not blinking. Any info would be appreciated. Thanks.

E45 is a problem with the fresh/recirculated air damper. Most often caused by something being dropped down the vents below the back window and jamming the works up, but shouldn't cause poor A/C in itself.

If E is showing in the display when it is switched on, then at least one fault must be active or the E would not show up. Does your machine have an electric condenser fan? Check that it is working. If it is, or you don't have one then you need someone to come out and put the gauges on it.

Edit. Or if you don't have an electric condenser fan and the condenser is part of the radiator pack, check that it is clean.

The 320C has a multiflow condenser with a tight fin pattern. Some will have their own fan and others may not. If it does not have a fan you need to make sure it is clean behind it and that you are getting good airflow. Throw the gauges on it to see what the pressures are - this system needs to be charged to the specific weight of refrigerant shown - or even a bit light is OK. Too much and you will have issues with high pressure and low performance. Too many techs in the areas I have worked in - and this includes dealer service techs - charge to the gauges (whatever that means) and not to the specified weight for the system. If you need to open the system for any reason you may as well change the drier while you are there. Charge to the weight specified and don't forget to replace any oil that you have recovered. If you have more than 5000 hours on the machine and haven't had the compressor changed, pull the plate off the front of the clutch and check for oil streaking. If you see any radial streaks from the center out, you likely have a leaking shaft seal - replace the compressor because you have or will shortly have a refrigerant leak as well. To confirm if you have a leak when you have the cover off, then pull the center hub of the compressor (clutch plate) and see if there is any moisture in the center hub of the shaft. If so, the compressor shaft seal is leaking and you need to replace the compressor. Some people will want to replace just the seal, but it is not cost effective with a new compressor costing $300 or less if you buy it from a non-Caterpillar source.

Having fun in the Texas heat!!