Scroll Compressor Application Guidelines - Desco Energy

AE4-1318The listed crankcase heaters (Table 3) are intendedfor use only when there is limited access.The heaters are not equipped for use with electricalconduit. Where applicable, electric safety codesrequire heater lead protection, a crankcase heaterterminal box should be used. Recommended crankcaseheater terminal cover and box numbers arelisted in Table 3A. If there are any questions concerningthe application, contact the Copeland ApplicationEngineering department.TABLE 3ACONDUIT READY HEATER BOX KITSModel NumberKit NumberZB50, ZB58, ZB66 998-7029-00ZB76, ZB88ZB56, ZB75 998-7015-00ZB92, ZB11MPressure ControlsBoth high and low pressure controls are requiredand the following are the minimum and maximumset points. Refer to Table 5 for proper settings.TABLE 5PRESSURE CONTROL SETTINGSModel Control R404A/R507 R134a R22Ty peZB50,ZB58, Low 17 psig min. 4 psig min. 37 psig min.ZB66, High 454 psig max. 263 psig max 381 psig maxZB76ZB88 Low N/A N/A 37 psig min.High N/A N/A 381 psig maxZB56,ZB75, Low 17 psig min. 4 psig min. 37 psig min.ZB92, High 454 psig max. 263 psig max 381 psig maxZB11MDischarge Line ThermostatThe thermostats have a cut out setting that willinsure discharge line temperatures remain belowthe 260°F maximum limit. It should be installedapproximately 7 inches from the discharge tubeoutlet. If a service valve is installed at the dischargetube, the thermostat should be located 5 inchesfrom the valve braze.Kits have been set up to include the thermostat,retainer, and installation instructions. Thesethermostats must be used with 7/8” O.D. dischargelines to ensure proper thermal transfer andtemperature control. They work with either 120 or240-volt control circuits, and are available with orwithout conduit ready connections. See Table 4 fora list of discharge line thermostat kit numbers.ModelDischargeT-StatT-Stat KitNumberConduitReadyZB50ZB58 Thermostat 998-0540-03 NoZB76 Required 998-7022-05 YesZB88ZB56ZB75ZB92ZB11MTABLE 4Internal Discharge TemperatureProtection ProvidedNo thermostat requiredIPR ValveThe 7.5 through 15 horsepower refrigeration scrollcompressors DO NOT have an internal high pressurerelief valve. To provide safe operation, a highpressure control set no higher than 445 psig mustbe used in all applications (reference Table 5).Motor ProtectionThe larger horsepower refrigeration scroll compressorshave either line break protection or theuse of sensors with an electronic module. The typeof protection is obtained from the protector code inthe model number. Table 6 lists the various modelsprotector number and the type of protection.TABLE 6MOTOR PROTECTIONModels with Line Break ProtectionZB50, ZB58, ZB66, ZB76, ZB88 No Module(note: electric code = TF*)Models with Electronic ModuleZB56, ZB75, ZB92, ZB11M P/N: 071-0547-01(note: electric code = TW*)3©2002, 2003 Copeland Corporation.Printed in the U.S.A.