Related Manuals for Emerson Copeland Scroll ZH13 KVE
Summary of Contents for Emerson Copeland Scroll ZH13 KVE
- Page 1 Scroll compressors with vapour injection for Dedicated Heat Pumps ZH13 KVE & ZH18 KVE...
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Page 2: Table Of Contents
™ ™ … … Introduction ................................2 Safety Instructions..............................2 EVI Theory of Operation ............................3 Nomenclature...............................5 Qualified Refrigerant ............................5 Application Envelope ............................5 System Configuration............................6 Liquid Extraction .............................6 Heat Exchanger Piping Arrangements ......................6 System Design Guidelines:..........................7 Heat Exchanger sizing using Select .......................8 Liquid and Vapour Injection Line Sizing......................8 Heat Exchanger TXV Sizing ...........................8 Solenoid valve..............................9 Lubrication................................9... -
Page 3: Introduction
Introduction This guideline describes the operating characteristics of the scroll compressors with vapour injection (ZH EVI) for dedicated heat pumps: ZH13KVE to ZH18KVE. Liquid injection is not approved for these models at this time. EVI Compressor systems benefit over standard refrigeration compressor systems of equivalent capacity due to the following: •... -
Page 4: Evi Theory Of Operation
EVI Theory of Operation Copeland EVI Scroll compressors are equipped with a vapour injection connection for Economizer Operation. Economizing can be accomplished by utilising a subcooling circuit similar to the circuit shown in Figure 1. This increases the refrigeration capacity and the system efficiency. The benefits provided will increase as the compression ratio increases. - Page 5 Condenser Subcooling Superheat at H/X Outlet ∆T ∆T Temp Diff, Subcooling in Heat Exchanger Figure 2. EVI P-h chart Definition(s) Description Condensing Temperature Liquid temperature entering H/X Subcooled liquid leaving H/X Intermediate Pressure Saturated temperature at intermediate pressure Vapour temperature leaving H/X Vapour temperature entering H/X Liquid subcooling in H/X Evaporator Mass Flow...
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Page 6: Nomenclature
Nomenclature The model numbers of Copeland Scroll™ compressors have been designed to include a coded nominal capacity at ARI operating conditions in BTU/h at 60 Hz without vapour injection All scroll compressors for dedicated heat pumps are charged with ester oil, which is indicated by the letter “E”. Model Designation Z H 18K V E - T W D - 5 24 Compressor family: Z = Scroll... -
Page 7: System Configuration
System Configuration Liquid Extraction Upstream liquid extraction (before the heat exchanger) is recommended as it optimises the heat exchanger performance. The TXV regulates the flow of subcooled refrigerant out of the condenser and into the heat exchanger (Figure 4). Minimum level of condenser natural subcooling has to be guaranteed at the TXV inlet to avoid flash gas, which would cause the valve to hunt. -
Page 8: System Design Guidelines
System Design Guidelines: The following sections discuss system design guidelines for the EVI product. Please use Copeland Selection Software (SELECT), where all parameters are given for selecting a single heat exchanger. The Copeland Selection Software can be downloaded from www.eCopeland.comT. The key parameter in determining the proper heat exchanger size is the Saturated Injection Temperature (Tsi). -
Page 9: Heat Exchanger Sizing Using Select
Heat Exchanger sizing using Select Figure 7 is an extract from SELECT which gives details of Economiser/heat exchanger load (kW) saturated intermediate temperature (Tsi) and sub-cooled liquid out of heat exchanger. 4K Natural Subcooling in Condenser Tsi temperature Liquid temperature leaving the heat exchanger Figure 7. -
Page 10: Solenoid Valve
Solenoid valve A liquid line solenoid valve is required to prevent migration of refrigerant to the compressor when it is switched off. For Multiple compressor application, a solenoid valve in the vapour injection line of each individual compressor is required. Each solenoid valve has to be energised in parallel to the compressor contactor. In the case of a single compressor application, the solenoid valve could be placed either on the liquid line before the Heat exchanger TXV or on the vapour injection line to the compressor. -
Page 11: Accumulators
The system should be evacuated down to 0.3 mbar or lower. If there is uncertainty, as to the moisture content in the system, an oil sample should be taken and tested for moisture. Sight glass/moisture indicators currently available can be used with the HFC refrigerants and lubricants; however, the moisture indicator will just show the moisture contents of the refrigerant. -
Page 12: Discharge Temperature Protection
12 Discharge Temperature Protection Internal discharge temperatures reached under some extreme operating conditions (such as loss of charge or extremely high compression ratio caused by failure of condenser fan) can cause compressor damage. In order to guarantee positive compressor protection the compressor must be equipped with an external discharge temperature sensor. -
Page 13: Electrical Installation
19 Electrical Installation Independently from the internal motor protection, fuses F6...8 have to be installed before the compressor as shown in Figure 14 and Figure 15. Selection of fuses has to be carried out according to VDE 0635 or DIN 57635 or IEC 269-1 or EN60-269-1. -
Page 14: High Potential Testing
20 High Potential Testing Copeland subjects all motor compressors to a high voltage test after final assembly. This is carried out according to IEC-34-1. Since high voltage tests lead to premature aging of the winding insulation we do not recommend additional tests of that nature. -
Page 15: Excessive Liquid Floodback
22 Excessive Liquid Floodback The following tests are for those Air/Water system configurations and charge levels, which need special testing to verify exemption from the need of an accumulator. 23 Continuous Floodback To test for excessive continuous liquid refrigerant floodback, it is necessary to operate the system in a test room at conditions where steady state floodback may occur (low ambient air/water heating). -
Page 16: Service
26 Service Copeland Scroll compressors have copper plated steel suction and discharge tubes. These tubes are far more robust and less prone to leaks than copper tubes used on other compressors. Due to the different thermal properties of steel and copper, brazing procedures may have to be changed from those commonly used. For brazing of the tubes see Figure 15 and the following procedures. -
Page 17: Shut-Off Valves And Adaptors
29 Shut-off Valves and Adaptors Scroll compressors ZH13KVE and ZH18KVE are delivered with brazing connections. Rotalock type shut-off valves can also fit compressors with braze connections (by the mean of Rotalock adaptors). Rotalock-shut-off valves are available for the suction as well as the discharge side (see Figure 18 & spare parts list “ZH”). Torque settings for Rotalock connections: Torque [Nm] Rotalock 1"-12UNF... -
Page 18: Suction Line Noise And Vibration
33 Suction Line Noise and Vibration Copeland Scroll compressors inherently have low sound and vibration characteristics. However, in some respects, the sound and vibration characteristics differ from reciprocating compressors and, in rare instances, could result in unexpected sound complaints. One difference is that the vibration characteristic of the Scroll compressor, although low, includes two very close frequencies, one of which is normally isolated from the shell by the suspension of an internally suspended compressor. - Page 19 Notes...
- Page 20 Tel. +32 (0) 87 305411 - Fax +32 (0) 87 305506 - internet: www.ecopeland.com - email: eCommerce@eCopeland.com The Emerson logo is a trademark and service mark of Emerson Electric Co. Copeland Corporation is a division of Emerson Electric Co. Copeland is a registered trademark and Copeland Scroll is a trademark of Copeland Corporation.