Trane RTCA 108-216 manual Drainage, Releasing the Nitrogen Holding Charge, Water Connections Rtub

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Installation

Drainage

Provide a large-capacity drain for water vessel drain-down during shutdown or repair.The evaporator is provided with a drain connection. All local and national codes apply. The vent on the top of the evaporator water box is provided to prevent a vacuum, by allowing air into the evaporator for complete drainage.

Releasing the Nitrogen Holding Charge

The nitrogen holding charge can be released into the atmosphere.

￿CAUTION

When releasing nitrogen holding charge, ventilate the room. Avoid breathing in the nitrogen.

Water Connections (RTUB)

Thoroughly flush all water piping to the unit before making the final piping connections to the unit.

￿CAUTION

If using an acidic commercial flushing solution, construct a temporary bypass around the unit to prevent damage to internal components of the evaporator.To avoid possible equipment damage, do not use untreated or improperly treated system water.

When making the water connections, use flange connectors. Insulate all piping to reduce temperature increases and to prevent condensation. Figure 7 shows all the piping systems for the evaporator and its components.The arrangement of the pipes and the other components varies slightly according to the positioning of the connections and the water source.

￿CAUTION

The chilled water connections to the evaporator are Victaulic connections. Do not attempt to weld these connections, because the heat generated from welding can cause microscopic and macroscopic fractures on the cast- iron water

boxes that can lead to premature failure of the water box.

A vent line is located on the top part of the evaporator at the water return piping end. Install additional vent lines at the highest points in the piping to vent the air present in the chilled water circuit. Install manometers to monitor the pressure of chilled water entering and leaving the evaporator.

￿CAUTION

To prevent damage to chilled-water components, do not allow evaporator pressure (maximum working pressure) to exceed 10.5 bars.

Provide shutoff valves in lines to the gauges, in order to isolate them from the system when they are not in use. Use rubber vibration eliminators to prevent vibration transmission through the water lines. If desired, install thermometers in the lines to monitor entering- and leaving-water temperatures. Install a balancing valve in the leaving-water line to control water flow balance. Install shutoff valves on both the entering- and leaving-water lines so that the evaporator can be isolated for service. A pipe strainer must be installed in the entering water line. Failure to do so can allow waterborne debris to enter the evaporator.

"Piping components" include all devices and controls used to provide proper water system operation and unit operating safety.These components and their general locations are given in Figure 7.

Entering Chilled-Water Piping

Air vents (to bleed air from system).

Water pressure gauges with shutoff valves.

Vibration eliminators.

Shutoff (isolation) valves.

Thermometers (if desired).

Clean out tees.

Pipe strainer.

￿CAUTION

Install a strainer in the evaporator- water inlet piping. Failure to do so can result in evaporator tube damage.

Leaving Chilled-Water Piping

Air vents (to bleed air from system).

Water pressure gauges with shutoff valves.

Vibration eliminators.

Shutoff (isolation) valves.

Thermometers (if desired).

Clean out tees.

Balancing valve.

Flow Switch

Evaporator Drain

A 3/4" drain connection is located under the outlet end of the evaporator water box.This may be connected to a suitable drain to permit evaporator drainage during unit servicing. A shutoff valve must be installed on the drain line.

Evaporator Flow Switch (accessory) The chilled water flow is protected by the UCM-CLD without the assistance of a chilled water flow switch.The flow switch is optional, but if it is not installed, a signal must be sent to the chiller to indicate the water flow is established, for example the auxiliary contacts of the chilled water pump starter.

If additional protection of the chilled water flow proves necessary, connect a flow switch installed on site, or a differential pressure switch to control the system's water flow. Connect the flow switch in series with the auxiliary contacts of the chilled water pump motor starter. A special connector is supplied with the unit, with the wiring diagrams. Some piping and control schemes, particularly those using a single water pump for both chilled- water and hot water, must be analyzed to determine how and/or if a flow- sensing device will provide the desired operation.

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RLC-SVX03A-E4

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Contents Installation Operation Maintenance Refrigerant Contents Operation Inspection Checklist General informationUnit Inspection Loose Parts Inventory Description of the UnitGeneral data Rtub General data Rtca Installation Installation responsibilities Storage Special Lifting and Moving Instructions IsolationFoundation Clearances Length Width HeightDrainage Releasing the Nitrogen Holding ChargeWater Connections Rtub Flow Switch Installation Water Pressure GaugesWater Treatment Refrigerant Safety Valves Installing and connecting temperature sensorsExtension of sensor power cable Water Pressure-Relief ValvesElectrical connections performed by the installer Connecting the Rtub with a remote air-cooled condenserDetail of positions of refrigerant sensors 5R56-1 and 5R6-2 Units on the same level Rtca or other manufacturers condenser below the Rtub Pressure tests and leak detection Equivalent pressure dropsSize of the liquid line Discharge lineVacuum pumping Vacuum pump connectionInstallation Checklist OperationPre-start checkout Unit Voltage PhasingStart-up Procedures OverheatingShutdown procedures SubcoolingSeasonal Unit Start-up System Restart After Extended ShutdownOperation Maintenance For units with the discharge valve option For units without discharge valve optionSome symptoms of a refrigerant under-charged unit Some symptoms of a refrigerant over-charged unitSome symptoms of an oil over- charged unit Checking the separator oil levelR134a Field-Charging Procedure Charge Isolation in the high or low side of the systemFilter Replacement Procedure Oil Charging ProcedureLubrication System Measuring the oil levelField Oil-Charging Procedure Factory initial Oil-Charging ProcedureMaintenance Safety recommendations Maintenance contractTraining