momo
15-08-2007, 09:01 PM
Been called to a Chinese Tango 11kW R22 Cassette A/C with 3ph Copeland compressor
Faults:
1.cuts out on freezing coil sensor bad or coil icing up according to local service call centre... to be checked.
2. leak from suction pipe.
Problem: this large (expensive) unit only has ONE service valve on the intermediate pressure! - located on the "liquid" line exit from the indoor unit :confused: (:D :rolleyes:)
Weighed in R22 to try acheive recommended pressure on line 8-10Bar ... could not acheive it, even when the suction line froze back past the suction tank to the compressor :eek: and refrigerant was past any reasonable charge :o.
On our next visit we will have to cut into liquid lines internally on unit and on suction line externally to see what's happening...
Due to difficulties with access and client times, fiestas :) etc visits to site are irregular, so:
A: Has anybody suffered any similar problems with this or other make's "cheapened"/simplified design and any other solutions?...
B: General practical question: When brazing a service valve into a 5/8" for the low pressure measurment:
Any comments about the angle and depth the 1/4 pipe take off point should have: if it the cut off faces flow will pressure be higher?, if it follows the flow will it be lower due to suction/venturii effect, therefore if square on will it be accurate... if so how much should poke into pipe?
Ultimately I suspect the compressor is worn out, but like any diagnosis without all the facts... before shocking the client about €€€€.çç.
Faults:
1.cuts out on freezing coil sensor bad or coil icing up according to local service call centre... to be checked.
2. leak from suction pipe.
Problem: this large (expensive) unit only has ONE service valve on the intermediate pressure! - located on the "liquid" line exit from the indoor unit :confused: (:D :rolleyes:)
Weighed in R22 to try acheive recommended pressure on line 8-10Bar ... could not acheive it, even when the suction line froze back past the suction tank to the compressor :eek: and refrigerant was past any reasonable charge :o.
On our next visit we will have to cut into liquid lines internally on unit and on suction line externally to see what's happening...
Due to difficulties with access and client times, fiestas :) etc visits to site are irregular, so:
A: Has anybody suffered any similar problems with this or other make's "cheapened"/simplified design and any other solutions?...
B: General practical question: When brazing a service valve into a 5/8" for the low pressure measurment:
Any comments about the angle and depth the 1/4 pipe take off point should have: if it the cut off faces flow will pressure be higher?, if it follows the flow will it be lower due to suction/venturii effect, therefore if square on will it be accurate... if so how much should poke into pipe?
Ultimately I suspect the compressor is worn out, but like any diagnosis without all the facts... before shocking the client about €€€€.çç.