Goodman Mfg RT6100004R13 manual Overcharge of Refrigerant, Checking Restricted Liquid Line

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SERVICING

S-111 CAPILLARY TUBES/RESTRICTOR ORIFICES

The capillary tubes/restrictor orifices used in conjunction with the indoor and outdoor coil, are a predetermined length and bore (I.D.).

They are designed to control the rate of liquid refrigerant flow into an evaporator coil.

The amount of refrigerant that flows through the capillary tube/ restrictor orifice is regulated by the pressure difference between the high and low sides of the system.

In the cooling cycle when the outdoor air temperature rises, the high side condensing pressure rises. At the same time, the cooling load on the indoor coil increases, causing the low side pressure to rise, but at a slower rate.

Since the high side pressure rises faster when the tempera- ture increases, more refrigerant flows to the evaporator, increasing the cooling capacity of the system.

When the outdoor temperature falls, the reverse takes place. The condensing pressure falls, and the cooling loads on the indoor coil decrease, causing less refrigerant flow.

A strainer is placed on the entering side of the tubes to prevent any foreign material from becoming lodged inside the capil- lary tubes.

If a restriction should become evident, proceed as follows:

1.Capture the refrigerant charge.

2.Removethecapillarytubes/restrictororificeortubestrainer assembly. and replace.

3.Replace liquid line drier, evacuate and recharge.

Discharge and suction pressures will be low, giving the appearance of an undercharged unit. However, the unit will have normal to high subcooling.

Locate the restriction, replace the restricted part, replace drier, evacuate and recharge.

S-113 OVERCHARGE OF REFRIGERANT

An overcharge of refrigerant is normally indicated by an excessively high head pressure.

An evaporator coil, using an expansion valve metering device, will basically modulate and control a flooded evaporator and prevent liquid return to the compressor.

An evaporator coil, using a capillary tube metering device, could allow refrigerant to return to the compressor under extreme overcharge conditions. Also with a capillary tube metering device, extreme cases of insufficient indoor air can cause icing of the indoor coil and liquid return to the compres- sor, but the head pressure would be lower.

There are other causes for high head pressure which may be found in the "Service Problem Analysis Guide."

If other causes check out normal, an overcharge or a system containing non-condensables would be indicated.

If this system is observed:

1.Start the system.

2.Remove and capture small quantities of gas from the suction line dill valve until the head pressure is reduced to normal.

3.Observe the system while running a cooling performance test. If a shortage of refrigerant is indicated, then the system contains non-condensables.

Capillary Tubes/Orifice Assembly

CHECKING EQUALIZATION TIME

During the "OFF" cycle, the high side pressure bleeds to the low side through the capillary tubes/restrictor orifices. Check equalization time as follows:

1.Attach a gauge manifold to the suction and liquid line dill valves.

2.Start the system and allow the pressures to stabilize.

3.Stop the system and check the time it takes for the high and low pressure gauge readings to equalize.

If it takes more than seven (7) minutes the capillary tubes/ restrictor orifices are inoperative. Replace, install a liquid line drier, evacuate and recharge.

S-112 CHECKING RESTRICTED LIQUID LINE

When the system is operating, the liquid line is warm to the touch. If the liquid line is restricted, a definite temperature drop will be noticed at the point of restriction. In severe cases, frost will form at the restriction and extend down the line in the direction of the flow.

S-114 NON-CONDENSABLES

If non-condensables are suspected, shut down the system and allow the pressures to equalize. Wait at least 15 minutes. Compare the pressure to the temperature of the coldest coil since this is where most of the refrigerant will be. If the pressure indicates a higher temperature than that of the coil temperature, non-condensables are present.

Non-condensables are removed from the system by first removing the refrigerant charge, replacing and/or installing liquid line drier, evacuating and recharging.

S-115 COMPRESSOR BURNOUT

When a compressor burns out, high temperature develops causing the refrigerant, oil and motor insulation to decom- pose forming acids and sludge.

If a compressor is suspected of being burned-out, attach a refrigerant hose to the liquid line dill valve and properly remove and dispose of the refrigerant.

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Contents Service Instructions Table of Contents Important InformationSafe Refrigerant Handling Product Identification Split System Air Conditioners R-22Split System Air Conditioners R-22 Split System Heat Pumps R-22 Product Identification Single Piece Air Handlers Single Piece Air Handlers MBR/MBE Air Handlers 036 036 120 3642 1824 Accessories ASC01CPKF24 CPKF36 CPKF42 CPKF48 CPKF60 CPKF61 Expansion Valve Kits FSK01A Coil Accessories Product Design Condensing UnitProduct Design System Operation HeatingCooling Cycle System Operation Indoor Coil Outdoor Thermostatic Expansion Valve AFE18-60A Control Board DescriptionTroubleshooting Chart COOLING/HP Analysis ChartServicing Table of Contents Checking Voltage Checking Wiring Checking THERMOSTAT, WIRING, and Anticipator3A Thermostat and Wiring Servicing3B Cooling Anticipator 3C Heating AnticipatorChecking Time Delay Relay Testing Coil CircuitChecking Transformer Control Circuit Checking Cycle ProtectorTesting Compressor Contactor Testing FAN RelayChecking Contactor AND/OR Relays Checking Contactor ContactsCopeland Comfort Alert Diagnostics Applies to ASC13 & ASH13Diagnostics Table Red TripHard Start KIT Wiring Testing Capacitor ResistanceChecking Loss of Charge Protector Checking CapacitorTesting Capacitance 15B Capacitance Check16A Checking FAN and Blower Motor Windings PSC Motors 16B Checking FAN and Blower Motor ECM Motors16D ECM CFM Adjustments 16C Checking ECM Motor WindingsChart on Next Chart from Previous Itc h 16E Checking GE X13TM Motors Checking Compressor17A Resistance Test GE X13TM Motor ConnectionsTesting Compressor Windings 17B Ground Test17D Operation Test Compressor Ground TestTesting Crankcase Heater Optional Item Testing Defrost ControlTesting Defrost Thermostat Checking Reversing Valve and Solenoid40 AR*F & MBR Electronic Blowers Time Delay Relay Sequence of OperationAR*F & MBR With Single Stage Condensers AR*F & MBR With Single Stage Heat PumpsAEP* & MBE Electronic Blower Time Delay Relay 41 AEP* & MBE with Single Stage CON Densers41A AEP* & MBE with Single Stage Heat Pumps Electric Heater Optional Item Temperature Rise F @ CFM 61A Checking Heater Limit ControlsLeak Testing Nitrogen or NITROGEN-TRACED 61B Checking Heater Fuse Link Optional Electric HeatersChecking Heater Elements Refrigeration Repair PracticeEvacuation EvacuationCharging Checking Compressor Efficiency An inaccurately charged system will cause future prob- lems105B Thermostatic Expansion Valve Overfeeding UnderfeedingSuperheat Thermostatic Expansion ValvesChecking Subcooling Checking Expansion Valve OperationOvercharge of Refrigerant Checking Restricted Liquid LineNON-CONDENSABLES Compressor BurnoutSuction Line Drier Clean-Up Method Refrigerant PipingInstallation Requirements Reversing Valve Replacement System ChargingAIR Handler External Static Coil Static Pressure DropTotal External Static Static Pressure DropALL Fuel System Control Board AFE18-60A Accessories Wiring DiagramsALL Fuel System AFE18-60A Control Board 10kw and Below, One Stage Electric Heat OT/EHR18-60 #2 GRD PLM PLF XFMR-R XFMR-C After Installing Optional Heat KIT, Mark AN X Provided Above HKR Heat Kit GRD PLM PLF Accessories Wiring Diagrams
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