Carrier 09DK Series Installation, Start-up And Service Instructions Manual

Contents

16REFRIGERANT LINE SIZING — Sizing depends on lengthof lines between various sections of the refrigerant system.Consider the amount of liquid lift and drop in the system aswell as proper compressor oil return. Consult Carrier SystemDesign Manual, Part 3, for proper piping sizes and design.LIQUID SHUTOFF VALVE AND SIGHT GLASS — Ashut-off valve is not supplied with 09DK condensers. It isstrongly recommended that a full line size liquid shutoff valve(see Fig. 18 and 19) be field supplied near condenser to allowfor servicing parts of the refrigerant circuit. A field-suppliedmoisture indicating sight glass is recommended for use incharging and servicing the system. Refer to Fig. 20.PRESSURE RELIEF — The American National StandardsInstitute and American Society of Heating, Refrigeration, andAir Conditioning Engineers Safety Code for MechanicalRefrigeration (ANSI/ASHRAE) 15 states the following:“Every refrigerant system shall be protected by a pressurerelief device unless so constructed that the pressure due to fireconditions will be safely relieved by some part of the system.”Since 09DK condensers have no pressure relief device, oneshould be field supplied and installed just before the liquid lineservice valve. (See Fig. 18 and 19.) When the split coil is usedwith multiple systems, each system must have its own pressurerelief.REFRIGERANT RECEIVER — A refrigerant receiver is notfurnished with 09DK condensers and is not recommended fornormal applications as its use will be detrimental to the desiredeffects of subcooling. However, if a particular applicationrequires a receiver to increase refrigerant holding capacity ofthe condenser, a receiver can be used. When a receiver is to beused all year, it should be installed indoors. Carrier recom-mends the following installation in such a case (see Fig. 20).Locate valves on each side of the receiver so receiver may beisolated from system for normal operation.*Field supplied.NOTES:1. Hot gas lines should rise above refrigerant level in condensercircuit.2. Trap should be installed on hot gas lines to prevent condenseroil and refrigerant vapor migration from accumulating on com-pressor heads during off cycle.3. Refer to Carrier System Design Manual, part 3 for proper pip-ing sizes and design.4. For piping lengths greater than 50 ft (15.2 m), provide supportto liquid and gas lines near the connections to the coil.Fig. 18 — Typical Piping for 09DK Condenser with a Single Compressor