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snow
04-04-2009, 05:33 PM
I went to a residence this morning to a not cooling complaint. At a glance what i found was
Outdoor Air temp. 68F
Suction Pressure 60 PSIG
Heat Pressure 150 PSIG
RLA 11.9
Atual Amps 7
All fans running
Compressor sounds like its running rough.
Was not able to get to the attic at the time, no one was there to let me in. could be air flow blockage also. It was reported that a air filter was sucked into the return but owner says its been like that for about 1 year and a half to 2 years
Suction line is cool not cold and liquid line does not get warm
What do you all think as to suggested problems.
I am thinking possible air flow blockage but this does not solve my rough compressor problems. give me suggestions please. Oh this is a carrier 2 ton split unit for the upstairs.

udarrell
04-04-2009, 07:52 PM
I went to a residence this morning to a not cooling complaint. At a glance what i found was
Outdoor Air temp. 68F
Suction Pressure 60 PSIG
Heat Pressure 150 PSIG
RLA 11.9
Actual Amps 7
(Probable Low Evap Load)
All fans running
Compressor sounds like its running rough.
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Snow; 68-F is very low ambient & indoor may be a light load.(?)

Not being able to get any indoor data eliminates many trouble shooting options. Always make sure someone is there so you can do the indoor diagnostics.

If you locate the SEER of the condenser, you could check the discharge air-temp rise split. This will indicate the heatload going through the evaporator coil.

A 12-SEER will usually be between 17 & 21-F delta-T or split. A high-side 150-psig with R-22 converts to 83-F minus 68-F ambient is a 15-F Temp-Rise-Split. That indicates an underloaded indoor coil, & is a bit low for a 12-SEER or lower rated condenser.

A higher SEER can have a 15-F condenser air split.
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Was not able to get to the attic at the time, no one was there to let me in. could be air flow blockage also. It was reported that a air filter was sucked into the return but owner says its been like that for about 1 year and a half to 2 years
Suction line is cool not cold and liquid line does not get warm.
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Could have a TXV metering device that is doing a fair job controlling the Suction Superheat & line Temp.

If you do a search for ' EER SEER efficiency ' you will probably find my web site with many diagnostic techniques.

Not enough diagnostic data here.
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What do you all think as to suggested problems.
I am thinking possible air flow blockage but this does not solve my rough compressor problems. Give me suggestions please. Oh this is a carrier 2 ton split unit for the upstairs.
Most of my replies are within the quote.
No one can accurately diagnose a system without access to the conditioned area.

universaltech
05-04-2009, 07:05 PM
You should probably look for that filter.