I WOKE UP TODAY TO FIND THE AC UNIT NOT COOLING PROPERLY. IT WAS SET TO 70-72 DEGRESS BUT THE HOUSE WAS 78-79 DEGRESS. I CHECKED THE AC UNIT AND IT WAS FROZEN. ACUTALLY, THE AIR FILTER WAS STUCK TO THE AC UNIT BECAUSE IT WAS FROZEN. I CALLED A LOCAL AC REPAIR COMPANY AND THE GUY THAT I SPOKE WITH SUGGESTED THAT I TURN OFF THE AC BUT LEAVE THE FAN RUNNING AND LET IT DE-ICE NATURALLY, WHICH I DID AND ALL THE ICE WAS GONE WITHIN 2 HOURS. I HAD A REPAIR GUY COME OVER TO CHECK OUT WHAT WAS GOING ON AND HIS FIRST DIAGNOSIS WAS THAT IT NEEDED FREON. SO, HE PUT 2 CANS OF FREON BUT NOTED THAT THE UNIT WAS NOT TAKING THE FREON AS EASILY AS HE WOULD HAVE LIKED. HE CHECKED THE INSIDE UNIT AND CAME BACK AND TOLD ME THAT THERE WAS A METERING PROBLEM AND HE RECOMMENDED THAT I REPLACE EITHER THE INSIDE UNIT ABOUT $1500 OR BOTH THE IN AND OUTSIDE UNITS $3400. AROUND THIS TIME HE HAPPENED TO NOTICE THAT OUR UNIT WAS 17 YEARS OLD. HE SAID THAT WE COULD LET IT RUN THE WAY IT IS NOW BUT THAT WE WERE NOT GET AS MUCH COLD AIR AND THAT IT WOULD ICE BACK UP AGAIN. ALSO, WHILE HE WAS INSPECTING HE HAD THE AC UNIT OFF AND AT ONE POINT TURNED THE HEAT ON, BUT THE HEAT WORKED FINE. I FELT THE HOT AIR WITHIN SECONDS COMING FROM THE VENTS. SO, SHORTLY BEFORE HE LEFT I TRUNED THE HEAT OFF AND PUT IT BACK ON COLD. THE GUY WENT TO OUTSIDE UNIT AND THIS TIME AFTER I TURNED THE AC UNIT ON TO COLD ( AFTER IT HAD BEEN ON HEAT FOR ABOUT 10-15 MUNITES) HE WAS ABLE TO GET MORE FREON IN THE SYSTEM.
I AM GETTING A SECOND OPINION THIS WEEK BUT I WOULD LIKE TO KNOW WHAT COULD BE WRONG IF THE HOT AIR WORKS, THE OUTSIDE FAN WORKS ? WHAT WILL IT TAKE TO GET THE COOLING AIR WORKING AGAIN ? THE UNIT HAS BEEN WORKING GREAT UP UNTIL THIS MORNING. WE HAVE BEEN BLASTING THIS SUMMER BECAUSE OF THE EXTREME HEAT. NORMALLY WE HAVE IT SET FOR 75 DEGRESS BUT WE HAVE HAD IT SET TO 70-72 DEGRESS THIS SUMMER. THERE IS COLD AIR COMING FROM THE VENT IN THE UPSTAIRS BEDROOM, BUT THE VENTS DOWNSTAIRS HAVE VERY LITTLE COLD AIR. LASTLY, THE ONLY THING THAT WE HAVE DONE DIFFRENTLY WAS THIS PAST WEEK MY HUSBAND SHUT ALL THE VENTS DOWNSTAIRS TO BASICALLY FORCE ALL THE COLD AIR UPSTAIRS WE DID THIS OVERNIGHT BUT THE FOLLOWING MORNING HE OPENED ALL OF THEM BACK UP. SORRY FOR THE LONG POST, BUT ANY HELP WOULD BE VERY MUCH APPRICAITED BECAUSE I DON'T WANT TO MELT IN THIS SUMMER HEAT BUT I SURE AS HECK DON'T WANT TO SPEND $1500-$3400.

 

Let's start with the closing of the downstairs registers. You closed the registers AND then the unit froze up while the registers were still closed OR you closed the downstairs registers, then reopened them and then the unit froze up a few days later?? After you de-iced it, how did it cool? When you found the unit froze up, was the larger of the two pipes at the outdoor unit also frozen? Usually, if the cooling coil/filters/blower fan are dirty, or the air flow is reduced [such as by shutting half the registers] the cooling coil will completely freeze over. If you have a shortage of freon, the cooling coil will freeze but usually not all of it and the larger of the two pipes outside will be warm. Sometimes you'll have both. If the service guy did not use an electronic thermometer and take a temperature reading on both pipes outside as well as the pressure readings, then there is no way he can make an accurate diagnosis. I am troubled by this business of 2 cans of freon. What size were the cans? Maybe he was having trouble getting freon in because he had cans that were almost empty with very little pressure in them? If your system did in fact need refrigerant, the tech is responsible to at least locate the leak/leaks so you can make a decision about how to procede. So adding it up: he puts in an unknown amount of freon, then says you have a metering problem, then says it will ice up again, BUT he did a half baked diagnosis. My best guess right now is that you probably have a dirty cooling coil and adding the freon has now overcharged the system which is bad news. Go outside and feel the larger pipe. Let us know how cold it feels and also fill in some of the other gaps. [my questions]

 

You've gotten some good sound advise from bigjohn, and here is a little more to add to it. Namely, find another HVAC technician. I'm aware its not easy to find experienced tech's these days, but the one that serviced you apparently doesn't have too many smarts.. Any tech worth his salt would have aty least done two things. One, determine if in fact there is a leak and two, make a determination if the indoor coil and blower are clean enough that the system CAN be properly charged. If the latter is at fault, then that must be resolved for a proper charge. So until you can have a good service tech come out, keep a clean filter and do not close off any more than 20% of your registers. In fact running the unit in its present state isn't a good idea for the compressor's sake. Good luck.

 

The unit froze up a few days later after we re-opened the downstairs vents. After I de-iced it, it cooled nicely just like normal but it did take a little while because the house got really warm becuse of the heat outside, but within a few hours it was nice and cool in the house. None of the pipes outside or inside were frozen, they all seemed normal temperature to my touch. As far as the the size of the freon cans, they looked like short round jugs. The tech at first said that there was a leak somewhere but he did not locate the leak. I noticed today that when I came home, more than 2 days after I de-iced it and it started cooling again normally that the unit started to freeze up again so I al letting it de-ice again and will see what happens after that. I agree with your assessment of the cooling coil because when I put in the new air filter on Saturday it looked dirty and I was almost tempted to just start manually picking off the lint and dirt that I can see myself. What do you think. Thanks bigjohn & ahasbeen very much for your help and helpful suggestions they are very much appriciated.

 

If there's no leak then what you have is a system with a dirty cooling coil and too much refrigerant. If the metering device is cap tube or orifice, you have a recipe for a compressor failure. I would clean that coil right away even if you have to make a mess in the house. Or, have another service company come out, remove the coil, clean it thoroughly, replace it, make sure there are no leaks, install a new filter drier, evacuate and recharge with your freon. [if they recover the freon, the freon they take out belongs to you insist that they weigh it when they take it out-they might be able to pump all the freon into the outdoor unit] this type of work isn't going to be cheap. If you're thinking $150, think more like $300 to $500.

 

bigjohn-I cleaned the inside cooling coil and I can't believe how dirty it actually was. I cleaned until there was no dust and no blobs of lint and I did this to one of the vents upstairs and I can already tell the diffrence in air flow, the cool seems to be flowing more freely. Thank you very much for all of your help. I truly appriciate all of your help. I will keep you updated as to what happens tomorrow. Thanks again !