York YPAL 060 User Manual

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JOHNSON CONTROLS
FORM 100.50-NOM6 (1207)
Example:  
The suction pressure is 130 PSIG and the 
suction line temperature is 57 °F
Suction Line Temperature  
 
= 57°F
Saturation Temperature for 130 PSIG 
= 45°F
Evaporator Superheat 
   
= 12°F
When adjusting the expansion valve, the adjusting 
screw should be turned not more than one turn at a time, 
al low ing  suf fi  cient  time  (ap prox i mate ly  15  min utes) 
be tween ad just ments for the system and the ther mal 
ex pan sion  valve  to  re spond and stabilize.
The superheat setting should be adjusted to 12°F at 
design conditions.
Leak Checking
Leak check compressors, fi ttings and piping to assure 
no leaks.  Verify the evaporator distributor tubes do not 
have bare copper touching each other or are against a 
sheet metal edge.  If you are leak checking a unit charged 
with R-410A make sure the leak test device is capable 
of sensing refrigerant R-410A.
If the unit is functioning satisfactorily dur ing the 
ini tial op er at ing period, no safeties trip and the unit 
controls are functioning prop er ly, the roof top unit is 
ready to be placed into operation.