Originally Posted by
NETWizz
To answer your question, you do not necessarily have a lemon in that each problem was a different problem, and fixing the problem properly likely yields a system good as new. It could run without further issues for 10 years OR perhaps it breaks tonight while you sleep.
At any rate the RX-11 flush is pretty common and a good practice when installing a new system on an existing line-set especially if changing from an HCFC to an HFC refrigerant OR doing a burn-out clean-up.
The schrader valve leak completely explains the loss of a pound of refrigerant the first year. Most likely it was caused from the installers cooking the service valve because they are often morons who have never wrapped a valve in in a wet rag or similar, yet think nothing of taking an oxy acetylene torch to it for brazing hot enough to turn the copper red-hot, yet somehow they do not care about the rubber-like service valve gaskets. You are lucky if it is only the schrader valve that leaked and not the actual service valve itself. If one schrader was fried, I would replace them both. I would probably have the next tech sniff under the service valve caps to verify.
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At any rate, replacing the coil is unfortunately a common task as well, and you got a new coil, so that issue is resolved.
Capacitors also do not last long with regard to Chinese and Mexican ones. The default manufacturer's brand is often something like Tong Feing (China) or Genteq (Mexico). Personally, my system was installed in 2015, and I cannot remember if I replaced the cap in 2018 or 2019, but I went with one made in the USA with a 5 year warranty.
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You mentioned the system is NOT keeping up like it once kept up.
What is the delta-t from where the filter is to an air vent? i.e. Using a thermometer, what is the air temperature at each location? Has it changed since last year?
My first question for you would be, are both fans constantly running inside and outside? You don't see any icing up on one of the copper lines near the inside unit do you?
I would also inquire when was the last time the air filters were changed? I cannot tell you how many calls we see where the systems cannot breath and loose a LOT of BTU.
Lastly, how does the outdoor unit's coil look? Is it dirty? When was it last cleaned, and how was it cleaned?
Lastly, if you want to check something else, outside there are two copper pipes going to the outdoor unit. A skinny one just under half an inch (usually 3/8") and there is another copper pipe that is usually about one inch (really 7/8" is the most common).
If you have a thermometer (i.e. a digital meat thermometer), you can take the temperature of both of those copper lines and report it back to us here if you like. The thermometer tip would need good contact like being tapped to the copper with a piece of electrical tape or similar and if you want a little foam tucked around it for a few minutes to get as accurate a reading as you can.
These numbers would help us give you some input though we cannot really diagnose a system without seeing it, sometimes we see something obviously wrong and will advise you to get a technician out to address an issue. If the outdoor unit has never been cleaned, it has been five (5) years, and I would suggest you call a technician to come out and perform that service, but make it clear you expect the top removed and a full inside-out cleaning with at least a mild coil cleaner. This is because it is of little value to you if another person spends 5 minutes hitting the outside with a garden hose in that it might help, a real professional service goes above and beyond that into the realm home-owners should NOT do because of the danger of electrocution and injury... but a good tech can really clean that coil. To complete the maintenance, you can reasonably expect the condensate drain be vacuumed and perhaps some pan tablets placed into the inside unit.
I would surely make sure the outdoor coil is clean AND the indoor filter are cleaned BEFORE the tech starts checking charge. Then, you if you want you can ask the tech if you have a piston or a TXV. If he says piston, you should see the tech taking a temperature reading inside (with something that is not an infrared thermometer) and outside with a thermometer. (Inside it will really be a psychrometer, which measures the humidity too to determine the sensible and latent heat load). If the technician says you have a TXV, then he or she likely has no need to go into your house to get a temperature reading just to charge the unit. At any rate after all that, outside you should see the tech take an outdoor temperature regardless, and the tech will at that point hook up the gauges AND some type of temperature probes to the copper lines. Often times these look like jumper cable clamps and have a little cable going back to a thermometer or digital gauges. Some new ones are a wireless sensor.
Simply put properly charging a unit one must take into impact the type of system you have, environmental factors (inside and out), pressure, and temperatures.
Charging a system properly or determining its charge is NOT merely like putting air in a car tire.
If you hire someone who merely connects some hoses from a manifold gauge set, next time get a different technician because that person is a hack. Now if a system is severely low or has a major problem like a restriction, a seasoned tech can immediately spot if something is WAY off just by connecting gauges. For example if you have an R-410a system and typical pressures are maybe 110 PSI to 135 PSI low-side depending upon all of the above and more, and the system is showing 70 PSI, there is a HUGE problem.
Just the same if you touch the copper pipes, and the big one is not sweating (i.e. colder than dewpoint) and it feels like maybe 70 F or 80 F... definite problem that does not take gauges to know there is an issue. If the skinny copper pipe is so hot you can barely touch it... HUGE problem!
By HUGE problem, I do not necessarily mean expensive like replacing a coil. I simply mean it warrants investigation and action that only a tech can perform. It simply would not be correctable by a home-owner. For example a HOT skinny copper line (liquid line) could be as easy to fix as a detailed cleaning of the outdoor unit, but again level of cleaning is NOT a task for a homeowner in that to do it properly the top needs to come off and there are electrical and other injury hazards like should the motor start while being removed.
I hope that makes sense. You can always spot a pro from a hack, BUT a professional with his hands, eyes, and ears can often tell immediately what a problem is not even needing all of the tools of the trade.
^^^ All of this and more are the real job and why you need a seasoned tech. After five (5) years, somebody best be cleaning the outdoor coil and not merely slapping on some gauges and adding some Freon like filling a car tire.
When you DO next see a tech, ask the tech for some BRASS caps over the schraders. You might even ask if he wouldn't mind putting a dab of Nylog on the cap rubbers. He will know what that means.
At any rate your system not keeping up could merely be from lack of maintenance. I see it everyday on systems a lot younger than five years too. You would be AMAZED how much better a system will work when the outdoor system is professionally cleaned and the air filters changed. Oh, and when you get filters, if you have those standard 1" thick ones, do NOT buy the pleated MERV 10 or Honeywell or 3M 9000 or whatever it is they sell. You want the cheaper filters that you can see light through because they allow for more airflow than the expensive ones. Tech tip... Using some masking tape, you can tape around the borders of the air filters to keep blow-by unfiltered air from going around the filter. This would REALLY keep the indoor coil clean and free of debris.