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46
Diagnostics
9.0 DIAGNOSTICS & TROUBLESHOOTING
9.9 Service Analyzer Charts (cont.)
THERMOSTATIC EXPANSION VALVES (cont.)
SYMPTOM
POSSIBLE CAUSE
REMEDY
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Install trap riser to the top of the evaporator coil.
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needed
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suction pressure
Unequal evaporator circuit loading
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Superheat and
suction pressure
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Sensing bulb is affected by liquid refrigerant or
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Relocate sensing bulb in another position around the
circumference of the suction line.
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circuits
Ensure sensing bulb is located properly.
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and recharge.
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regulate at all
External equalizer line not connected or line
plugged
Connect equalizer line in proper location, or remove any
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Sensing bulb lost its operating charge
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improper installation
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