New Carrier straightcool
What do you guys think about a spilt carrier straight cool, that has been vac and micron gauged, with a weighed in charge put in, but only has a 10 degree split at the evap coil? Subcool was ~40 degrees with ~8 degrees superheat. I tried to purge the unit to lower the subcooling to 16 then to 10 then 6 degrees but has no effect on the temp. split. No restrictions in filter drier, so does it have to be the TXV or is there another option?
You are not telling us what the actual pressures were.
I don't know how you could purge from 40-F to 6-F Subcooling. (?)
How much airflow do you have & how high is the humidity.
Could it be pulling hot moisture laden air from the attic into the return.
At 400-cfm per/ton of cooling, an 80-IDB & 74.5-IWB will produce around a 10-F SA/RA delta-T split. What were indoor conditions?
Maybe the airflow is 475 to well over 500-cfm per/ton of cooling, it can happen with wrong speed selections, & the new powerful & sometimes oversized air handlers.
Humidity is low as I am im phoenix, arizona. pressures were on the low side 53 degrees or ~135psig and 135 degrees on the high side or ~500psig. After I put some 410a into my recovery tank to get the subcooling down pressures were at 125/420 indoor was 81, outdoor was 118
What model and serial number?
Might want to do a static pressure versus temperature test to see that the refrigerant is pure.
I thought the person who did the start up left nitrogen in the unit or ... so I pulled a good vac and weighed in my charge.. the right way :) or so I think.. both the condenser/coil are 6 months old... model number coil CNPVP6024ACAAAA, condenser 24ABA360A320, the unit next to it is identical.
R410A at 135 PSIG has a sat temp of roughly 48°F.
Get all the readings, not just is was 135 psi suction line.
Also need all the temps.