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Is this expected of an inefficient compressor?

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onecallplus

Mechanical
Jul 30, 2015
3
I am working on a fixed orifice Goodman 2.5 ton unit. Both coils are squeaky clean, clean filter, replaced damaged ducts in attic using R-8 flex; airflow is 1100 CFM over evaporator and air handler is not leaking air into attic.
Delta T on evaporator is 3 degrees when target super heat is obtained.
here are my readings from SMAN-3
LS 92.4 psi
Liquid 239.5
SH 12.5
SC 27.5
SH Target 20.8
IDWB 70.0
ODDB 88.7
VSAT 54.8
LSAT 114.6
Suction line 67.4 and liquid line 86.5 degrees

When I started unit was greatly overcharged and had disintegrating attic ducts and a dirty condenser coil. If i get VSAT in the 40-45 range and LSAT 100-105 the SH goes to 37 and SC a respectable 14. With that high super heat i have 67 or so suction pressure and 210 or so head pressure. This has me stumped or I would not be asking for help. Can anyone draw any rational conclusions from this data. Oh, the compressor is a reciprocating. I have considered bad valves, but am not certain that my numbers confirms that. So, in a word, "HELP"
 
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I am sorry that I omitted that, but with those pressures it is either R-22 or propane. The answer is R-22. Do you have more questions or thoughts about this?
 
Possibly there is air in the system. Or it might have been topped up with who knows what at some point.

Recover everything, pull a good hard vacuum and recharge with known good R-22. See if that improves things.
 
Tx, I have considered doing just that, but if it doesn't solve the problem it is a major useless expense to the customer. I don't like charging for work that doesn't solve problems. I will be thinking about it some more before getting back to them. Maybe I will stumble upon a definitive test procedure.
 
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