Model number: 50TFF006---511--
Serial number: 2702G10324
I get a call that an a/c unit is leaking water into the building. I thought it would be easy. Jump up on the roof and blow the drain out, but it turned out to be a little bit harder.
The drain is now clear. I put water in the pan and it flows down the drain with no problems. When the unit runs, water collects on the evaporator coil and instead of running down the coil and collecting in the pan it just drips right of the coil and into the return duct. (The coil is slanted at a 45 degree angle).
I took a temperature split across the coil and checked static pressure across the coil.
Temp. split: 79* -- 56*, 23*
Static pressure: -.24 -- .16, .40
Maximum allowable external static pressure for this unit is .75 in w.c.
Just to let you guys know, I don't really understand static pressure that well.
I let my boss know what I found and he told me that you are only allowed 40% of your max static pressure across the coil. If your reading is higher, then you have a plugged evap coil. Since 40% of .75 is .30 then my static pressure of .40 is too high. I removed the filters and flushed out the evap coil with a garden hose, trying my hardest to not get a lot of water in the duct.
I left the filters out and took another static pressure reading across the coil.
Static pressure after flushing coil w/ no filters: -.11 -- .16, .27
The new reading is under .30 which means I have good airflow across my evap coil. The water is still dripping off the coil into the return and not into the drain pan. My boss tells me to check refrigerant pressures and add a little gas if the suction is under 70. My suction is at 60 so I add gas to bring it up to 70. Still I have water dripping off the coil instead of down the coil.
I'm stuck guys. I wish my company only fixed refrigeration equipment and stayed away from a/c. What should I check/do?