Carrier 17 Start Up & Operation Manual

Contents

CONDENSER — Since this water circuit is usually an open-type system, the tubes may be subject to contamination andscale. Clean the condenser tubes with a rotary tube cleaningsystem at least once per year, and more often if the water iscontaminated. Inspect the entering and leaving condenser wa-ter sensors for signs of slime, corrosion, or scale. Replacethe sensor if corroded or remove any scale if found.Higher than normal condenser pressures, together with theinability to reach full refrigeration load, usually indicate dirtytubes or air in the machine. If the refrigeration log indicatesa rise above normal condenser pressures, check the con-denser refrigerant temperature against the leaving condenserwater temperature. If this reading is more than what the de-sign difference is supposed to be, then the condenser tubesmay be dirty, or water flow may be incorrect. BecauseHFC134-a is a high-pressure refrigerant, air usually does notenter the machine, rather, the refrigerant leaks out.During the tube cleaning process, use brushes especiallydesigned to avoid scraping and scratching the tube wall. Con-tact your Carrier representative to obtain these brushes. Donot use wire brushes.Hard scale may require chemical treatment for its pre-vention or removal. Consult a water treatment specialistfor proper treatment.Water Leaks — Water in the refrigerant is indicated dur-ing machine operation by the refrigerant moisture indicatoron the refrigerant motor cooling line (Fig. 8). Water leaksshould be repaired immediately.Machine must be dehydrated after repair of water leaks.See Machine Dehydration section, page 51.Water Treatment — Untreated or improperly treated wa-ter may result in corrosion, scaling, erosion, or algae. Theservices of a qualified water treatment specialist should beobtained to develop and monitor a treatment program.Water must be within design flow limits, clean, and treatedto ensure proper machine performance and reduce thepotential of tubing damage due to corrosion, scaling, ero-sion, and algae. Carrier assumes no responsibility forchiller damage resulting from untreated or improperlytreated water.Inspect the Starting Equipment — Before work-ing on any starter, shut off the machine, and open all dis-connects supplying power to the starter.The disconnect on the starter front panel does not de-energize all internal circuits. Open all internal and re-mote disconnects before servicing the starter.Never open isolating knife switches while equipment isoperating. Electrical arcing can cause serious injury.Inspect starter contact surfaces for wear or pitting onmechanical-type starters. Do not sandpaper or file silver-plated contacts. Follow the starter manufacturer’s instruc-tions for contact replacement, lubrication, spare partsordering, and other maintenance requirements.Periodically vacuum or blow off accumulated debris onthe internal parts with a high-velocity, low-pressure blower.Power connections on newly installed starters may relaxand loosen after a month of operation. Turn power off andretighten. Recheck annually thereafter.Loose power connections can cause voltage spikes, over-heating, malfunctioning, or failures.Check Pressure Transducers — Once a year, thepressure transducers should be checked against a pressuregage reading. Check all three transducers: oil pressure, con-denser pressure, cooler pressure.Note the evaporator and condenser pressure readings onthe Status01 screen on the LID. Attach an accurate set ofrefrigeration gages to the cooler and condenser Schrader fit-tings. Compare the two readings. If there is a difference inreadings, the transducer can be calibrated, as described inthe Troubleshooting Guide section.Pumpout System Maintenance — For compres-sor maintenance details, refer to the 06D, 07D Installation,Start-Up, and Service Instructions.OPTIONAL PUMPOUT COMPRESSOR OIL CHARGE —Use oil conforming to Carrier specifications for reciprocat-ing compressor usage. Oil requirements are as follows:HFC-134aISO Viscosity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68Carrier Part Number . . . . . . . . . . . . . . . . . . PP23BZ103The total oil charge, 4.5 pints (2.6 L), consists of3.5 pints (2.0 L) for the compressor and one additionalpint (0.6 L) for the oil separator.Oil should be visible in the compressor sight glass bothduring operation and at shutdown. Always check the oillevel before operating the compressor. Before adding or chang-ing oil, relieve the refrigerant pressure as follows:1. Attach a pressure gage to the gage port of either com-pressor service valve (Fig. 34).2. Close the suction service valve and open the dischargeline to the storage tank or the machine.3. Operate the compressor until the crankcase pressure dropsto 2 psig (13 kPa).4. Stop the compressor and isolate the system by closingthe discharge service valve.5. Slowly remove the oil return line connection (Fig. 34).Add oil as required.6. Replace the connection and reopen the compressor serv-ice valves.82