Emerson AFA Hoja De Instrucciones

Instruction Sheet
PA-00235
June 2013
AFA(E) Thermal Expansion Valves
FEATURES
Emerson AFA & AFAE Thermal Expansion Valves are
designed to meet the specific demands of refrigerated
display cases, reach-in and walk-in coolers and freezers,
and commercial applications ranging from medium (+50°F)
temperature, with proper charge.
• Bar-stock body - SAE connections
• Internal or external equalizer
• Wrench flats on inlet and outlet - SAE
• Removable inlet strainer - SAE
• Corrosion-resistant materials
• Interchangeable with currently available commercial
refrigeration TEVs
SAFETY INSTRUCTIONS
WARNING: Before opening any system, make sure the
pressure in the system is brought to and remains at atmo-
spheric pressure. Failure to comply can result in system
damage and/or personal injury.
1. Read all instructions thoroughly. Failure to comply
may result in valve failure, system damage, or person-
al injury.
2. Do not use on service conditions or fluids not spe-
cifically cataloged, without prior written approval of
Emerson Climate Technologies Flow Controls Division
Applications Engineering Department. Use of ther-
mal expansion valves on applications not specifically
cataloged can result in valve failure and/or system
damage.
3. WARNING: Do not place open flame on or near bulb!
4. Protect against excessive vibration, it may cause a
tubing break which will cause valve failure.
5. Foreign matter in the thermal expansion valve may
cause diaphragm failure, flooding, or starving of the
valve. Use of an Emerson liquid line filter-drier is
strongly recommended.
6. Valves are factory set to a specific superheat. If
adjustment is needed, refer to Superheat Adjustment
section for proper procedure. Improper adjustment of
superheat can result in system damage.
7. Use back-up wrench on all wrench flats. Over-torqu-
ing can result in valve body damage.
8. Proper valve sizing is important. An oversized valve
may result in erratic control. An undersized valve
considerably reduces system capacity.
9. Do not exceed maximum working pressure of 450
psig, excess internal pressure could cause damage to
diaphragm, resulting in valve malfunction.
10. Do not exceed maximum working temperature (see
table 1) - excess temperature could cause internal
damage, resulting in valve malfunction.
EmersonClimate.com/FlowControls
AFA(E) Thermal Expansion Valves
INSTALLATION INSTRUCTIONS
WARNING: Before opening any system, make sure
1.
the pressure in the system is brought to and remains
at atmospheric pressure. Failure to comply can result
in system damage and/or personal injury.
2. Valves may be installed in any position, but should
be located as close as possible to the distributor or
evaporator inlet.
3. Be sure valve is installed with its flow arrow corre-
sponding to the flow direction thru the piping.
4. Attach the remote bulb to the suction line as close to
the evaporator outlet as possible. Position the bulb at
the 4 or 8 o'clock position. Clean surface of suction
line where the remote bulb is to be attached, and then
securely fasten the bulb with straps provided. If the
remote bulb can be affected by the surrounding ambi-
ent, then the bulb should be insulated with a material
that will not absorb water. See figure 1.
5. Connect one end of the external equalizer line to
the valve. Connect the other end to the suction line
slightly downstream from the remote bulb location and
positioned so that it cannot siphon oil from the suction
line.
6. Check of leaks, sufficient system refrigerant charge,
and be sure no flash gas is present before attempting
to check valve operation.
7. The expansion valve must be free of all contaminants
- install an Emerson liquid line filter-drier before the
valve.
8. On SAE Connections: Use special care to not over
tighten fittings.
Maximum Dehydration Temperature °F
REFRIGERANT
R12
R22
R502
This Table refers to the maximum dehydration
temperatures when the bulb and valve body are
subjected to the same temperature. On L, C, and Z
charges, 250°F maximum valve body temperature is
permissible (if the bulb temperature) does not
exceed those shown in the table.
TABLE 1
THERMOSTATIC CHARGE
C Z WMOP/CA
190 250 250
160 185 250
150 170 250