Air Condition Recharge

Finally located low side of A/C and had blue cap on it. Located on the front side of coach under windshield wiper assembly. Had to stick my head in over generator and look backwards. Removed cap, connect 134A canister to fitting. It registered at the bottom of gauge in blue. Took about 13-14 ounces of fluid. Had the unit set on max air and returned with cold air. Happy Camper.....
Thanks all for your input & help.

You do know that in the kind of heat we are having this week in much of the country A/C gets warmer too Proper outlet is a complex formula needing the temperature at the evaporator inlet, and outlet,, The condenser inlet, and outlet (Front and back) and the humidity inside and outside.

Then you go to the book of charts, find the one that applies and plot the readings.. Above the line is,as I recall (Each chart has a line) bad, below good.

They make R-134a freon recharge kits that contain stop leak. If you have a small leak, this may take care of that without spending a lot of money as suggested by some. A small leak is normal for most automotive systems and if a can of freon every few years takes care of it, then do it. The blue cap could have been removed and lost. Look for the valve, not the blue cap.

OP, it has to be after the expansion valve in the evaporator, so there or on the line back to the compressor, if not near the compressor.

Thanks all for your information and really appreciate your time taken to assist me with your advice. I have always found this forum very helpful and informative by some specialists and some by experiencing the same issues that we deal with on these monster toys.
I have located the high port which has a red cap and I will continue to search for the low port (blue cap)now that some of you have given me your free advice.,

Thanks,

The low side may have a blue cap on it.

There is an allowable amount of leakage for every joint and rubber hose in any automotive A/C system. About 10 to 25 grams a year. This is normal and is allowed per EPA and FMVSS standards. So if after 5 to 6 years your system cooling is lacking, yes you can top it off, and no it's not a leak, it's normal. Find the low side port, hook up the can and charge with gas.

DANO2014 wrote:
Appreciate the Info but my problem is locating the low side of the cooling unit. I don't think I have a leak because it has been putting out cool air for quite some time and by adding coolant or connecting to the low side the gauge should give me an indication if it is low or not?
Thanks again, I know just enough about A/C's, I could be dangerous!!

If it is not leaking but cooling has dropped off, where has the ability to cool gone? If it is not leaking, why is it necessary to locate the low pressure valve and add more R134a? That will only cause problems if not needed. Like someone else said, "find and fix the leak".

ScottG wrote:
If it's so low it wont run then it really needs to be evacuated (and the leak fixed) before adding any more refrigerant. Otherwise there are ramifications ($$$$).

BS... Read his post. It's working but not as good as usual. OP, it should take less than a can to top it off. Good luck in finding the port.

DANO2014 wrote:
Appreciate the Info but my problem is locating the low side of the cooling unit. I don't think I have a leak because it has been putting out cool air for quite some time and by adding coolant or connecting to the low side the gauge should give me an indication if it is low or not?
Thanks again, I know just enough about A/C's, I could be dangerous!!

Then you should know that Freon doen't wear out. You ether have a leak or your condenser is dirty or your ac coil is icing.
find someone you trust and have them look at it.