appears to be refrigerant leak...could be an easy repair...R22 refrigerant?...might be expensive due to refrigerant cost...please no gas n go...unacceptable practice...

IMO

Thanks tiger...what do you mean by "no gas n go" ? thanks again

also, sorry for the poor grammar in orig post - I was kind of bent out of shape thinking another $7000 payment is lurking in front of me again

a gas n go is a typical but unacceptable HVAC practice of recharging an outside AC condenser with refrigerant without finding and repairing a leak...just from a distance, it looks like you have a leak at a port...some leaks are repairable, others not so...R22?...

IMO

gas n go are quite rare today because of the cost of the refrigerant. If people have money to throw away I will do it with tail light warranty, but not without heavy warnings against such things -- but if you own a home, it's your decision to make not mine. Once my tail lights go out it's out of warranty. (there is no warranty on gas n go)

This situation isn't always due to refrigerant, that's probably what it is but it could be dirty filters or dirty indoor coils... the other rare situation is that it could be a restriction in the refrigerant line.

Because this unit was installed in 2004-5 you're right at the mark (very close) average replacement of 15 years. Repairing an R22 Freon unit these days is best only if you plan to sell the home fairly soon.

Every time it springs a leak, is going to put you in dire straights... due to refrigerant costs.

If additional readers are reading this: Get all your options to solve problems like this, I service the Katy, Texas area.

I did a visual inspect of the following:

Two filters upstairs to unit in question: all filters look clean

Inside the condensing unit: the compressor and tubing all look clean and no sign of leaking oil/Freon residual

Looked upstairs and nothing in the primary drain pan or anything indicating water or moisture...

The high pressure line returning to house coil seemed fine, couldn't hear any gurgling or anything else indicating air or other in line, but w compressor fan on, the noise and vibration is makes it's hard to tell anything..

turned on the unit [current temp was 79] and set thermostat to 77. The air coming out of ceiling registers seem pretty cool. The refrigerant/Freon cap was really cold upon start-up of condensing unit, then the coldness decreased at the cap [what is frozen in pic 1)

Temp dropped from 79 to 78, waiting to see if it cycles off. there's a lot of heat upstairs from last night, so it's taking a bit to remove it...temp is now at 77 but waiting to see if it cycles off...we have a cloudless day so I'm sure upstairs is getting warn anyway...

I post back later if anything else changes...

I would want to see several supply temps from the registers and also return temps. Note outside temp.

IMO

I need to buy a register temp gauge - any recommendations ?

Cheap digital at big box store...

I've used a $7 analog cooking thermometer from BB&B. They usually have the range and react fairly fast.

Without the proper equipment it's unlikely you will find the leak. Sometimes they are obvious due to oil leaking, but this isn't always the case it really depends on where the leak is. Refrigerant leaking will give no visible signs, it evaporates as soon as it hits the atmosphere. It would have to be a good size leak to be able to see the refrigerant, but it would all leak out fairly quick so it's not likely the leak (if that's what it is) is your problem.

While refrigerant restrictions are rare, they do happen.

If an AC system is freezing up there is always a reason. It could also be that the blower motor is starting to fail. If the blower slows to a crawl, there isn't enough air flow across coil, it would be the same effect if the coil was plugged with dirt.

With that said, guessing is not diagnosing. All I am doing here is guessing. True diagnosing is done in person by a professional.

agree with above and proper diagnosing...if a leak and that is more than likely, you will need a qualified HVAC tech. I still would like to know what supply and return temps you are getting.

IMO