Rheem ASL-JEC Series, Installation Instructions Manual

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THERMOSTATIC EXPANSION VALVES
SYMPTOMS POSSIBLE CAUSE CHECK OR REMEDIES
High Superheat, Low Suction Pressure Moisture freezing and blocking valve Recover charge, install filter-drier,
evacuate system, recharge
Dirt or foreign material blocking valve Recover charge, install filter-drier,
evacuate system, recharge
Low refrigerant charge Correct the charge
Vapor bubbles in liquid line Remove restriction in liquid line
Correct the refrigerant charge
Remove non-condensible gases
Size liquid line correctly
Misapplication of internally equalized Use correct TEV
valve
Plugged external equalizer line Remove external equalizer line
restriction
Undersized TEV Replace with correct valve
Loss of charge from power Replace power head or complete
head sensing bulb TEV
Charge migration from sensing bulb Ensure TEV is warmer than
to power head (Warm power head sensing bulb
with warm, wet cloth. Does valve
operate correctly now?)
Improper superheat adjustment Adjust superheat setting counter-
(Only applicable to TEV with adjustable clockwise
superheat settings)
Valve feeds too much refrigerant, Moisture causing valve to stick open. Recover refrigerant, replace filter-
with low superheat and higher than drier, evacuate system and then nor-
mal suction pressure recharge
Dirt or foreign material causing Recover refrigerant, replace filter-
valve to stick open drier, evacuate system and
recharge
TEV seat leak (A gurgling or hissing Replace the TEV
sound is heard AT THE TEV during
the off cycle, if this is the cause.)
NOT APPLICABLE TO BLEED
PORT VALVES.
Oversized TEV Install correct TEV
Incorrect sensing bulb location Install bulb with two mounting
straps, in 2:00 or 4:00 position on
suction line, with insulation
Low superheat adjustment Turn superheat adjustment
(only applicable to TEV with clockwise
adjustable superheat setting)
Incorrectly installed, or restricted Remove restriction, or relocate
external equalizer line external equalizer
Compressor flood back upon start up Refrigerant drainage from flooded Install trap riser to the top of the
evaporator evaporator coil
Compressor in cold location Install crankcase heater on
compressor
Any of the causes listed under Any of the solutions listed under
Symptoms of Problem #2 Solutions of Problem #2