Install Instructions

MEASURING SUPERHEAT
1. Determine the suction pressure with an accurate gauge
at the evaporator outlet (see P in figure 3). On self-
contained systems, the suction pressure may be read at
the compressor suction connections.
2. From refrigerant pressure-temperature tables, determine
saturation temperature at observed suction pressure
(TEMP
P
).
3. Measure temperature of suction gas at thermal expan-
sion valve remote bulb location (TEMP
T
).
4. Subtract saturation temperature (read from tables in step
2) from temperature measured in step 3; the difference
is the superheat of the suction gas.
SUPERHEAT ADJUSTMENT
Emerson thermal expansion valves are factory set to a
specific superheat - however, the superheat should be
adjusted for the application. To adjust the valve to other
superheat settings:
1. Remove the seal cap from bottom of valve.
2. Turn the adjustment screw clockwise to increase
superheat and counterclockwise to decrease superheat.
One complete 360° turn changes the superheat approxi-
mately 3-4°F, regardless of the refrigerant type. As
much as 30 minutes may be required for the system to
stabilize after the adjustment is made.
3. Replace and hand-tighten seal cap.
Caution: When adjusting superheat setting - when stop is
reached, any further turning adjustment will damage valve.
69 PSIG = 40°F
59 PSIG = 33°F
59 PSIG = 40°F
EXTERNAL EQUALIZER
59 PSIG
40°F
T
P
TEMP
T
– TEMP
P
= SUPERHEAT
40° – 33° = 7°
FIGURE 3
POWER ASSEMBLY REPLACEMENT
Warning: Before removing any power assembly, the system
must be brought to, and remain at, atmospheric pressure.
Failure to comply can result in system damage and/or
personal injury.
1. To remove the power assembly, first ensure the valve is
free of any moisture or ice. Do not heat valve with torch.
Use "heat gun" or apply hot rags to valve to melt ice.
2. Remove the remote bulb from suction line.
3. Turn power assembly counterclockwise with proper size
wrench, being careful not to damage body.
4. With power assembly removed, care must be taken to
prevent any foreign material from entering the valve.
5. Care must also be taken not to damage the threads or
surface area.
6. Install new power assembly with no oil or thread com-
pound, and torque to 375-425 in. lbs.