Heating Help

A\C stops working when cool outside

My parents are having a minor problem with their central air.  System works really good when its 80-90F outside but if its cooler out say around 70F the system completely stops blowing cold air.  The system starts out blowing good cool air but it slowly becomes warm.  Blower continues to run, compressor sounds normal and condenser fan is running.  highside line becomes cool and suction line is no longer cold.

Though it may seem odd to run the A\C when its that cool out the reason is the house gets warm during the day but my dad does not want to let the damp cold air in at night so he runs the A\C.  The area they live in tends to get very humid at nights.

Does this sound like a TXV problem?

weird

Does the condensing unit outside, and the compressor, continue to run even though it's not producing cooling? 

Yep

Sorry Paul I edited the post and added that just as you were replying.

Open Mouth Insert FEET!

 Without hi/lo pressurers,indoor/outdoor temps it's a crapshoot . Maybe a good guess, maybe. Shut the AC off ,indoor fan running for 2 3/4hours upto 4 hours. Start the AC up , and wait for the first 75* day or cooler. At the indoor blower  feel the liquid line, and, feel ! If you feel "something/anything" that feel's like "activity" the system is low on freon. If not, recheck at 71*,if not ! Next WAG!

No Cooling?

This is a classic example of a service call where the customer explains all that he observes and looks for advice on possible problems as to why the A/C does not work properly.  This is where we earn our money in this industry by experience and measurable figures so we can identify and correct the problem.  Remember we charge only a dollar to come to your house, and the rest of the total charge is because we knew where to look, what to test and how to repair the problem.  What a great value.  We even guarantee our work.  Since there are no facts other than "it's warm" I'll bet you a dollar that it's one of 20 possible problems.  Now that's a craps shoot.
In all seriousness, call a pro or try to give more information.  People who know me know I don't mean to be disrespectful.

Peace:
Mike T.

Empire

Sorry but with all due respect you are wrong.
I used to work on fixed orifice automotive systems as a hobby. I am also into restoring 1920s-30s GE monitor top refrigerators which use sulphur dioxide or methyl formate as refrigerants. Of course those refrigerators use a float controlled orifice and are VERY different. Point being I don't feel I am the typical homeowner and I have NEVER wasted a professionals time on the phone. I asked for opinions out of pure curiosity of my own. My parents are calling out the installer to have a look at the system.

I have three gauge sets none of which I can hook to the system because of them being used with PAG ( I assume the home system is mineral oil) ergo I cannot give any pressures. My favorite ones are a set of Yellowjacket Brute 2's I bought a few years back.

I realize you didn't mean to be disrespectful however I want to make sure you realize I had a reason for asking and it wasn't to save money and waste someone else's time.

Gauges

ChrisJ, a COUPLE of set's of gauges already( I have 15 or so),what's one more set of gauges?  And restoring that old stuff (for fun, right ?) ,you must have a good understanding of what's going on inside the refrigeration system ! On the P/T chart AC is anything above 32.1*F. The oil in home AC's can be mineral, or several different types of POE,depending on which freon .R-22 or R-410a .

Chris

Point taken and like I said, it was more of a general thought, not meant to even imply your capabilities.  Anyways I won't lose any sleep tonight.  The problem you stated is relatively straight forward so good luck with it.  I know a lot or techs that attack the problem from many different angles.  There is no wrong way.

Mike T.