Screw liquid chillers are designed to provide safe and reliable service when operated within design specifica- tions. When operating this equipment, use good judg- ment and safety precautions to avoid damage to equipment and property or injury to personnel.
Be sure you understand and follow the procedures and safety precautions contained in the machine instruc- tions, as well as those listed in this guide.
DO NOT VENT refrigerant relief devices within a building. Outlet from rupture disc or relief valve must be vented outdoors in accor- dance with the latest edition of ANSI/ASHRAE 15 (American National Standards Institute/American Society of Heating, Refrigera- tion and Air-Conditioning Engineers) (Safety Code for Mechanical Refrigeration). The accumulation of refrigerant in an enclosed space can displace oxygen and cause asphyxiation.
PROVIDE adequate ventilation in accordance with ANSI/ ASHRAE 15, especially for enclosed and low overhead spaces. Inhalation of high concentrations of vapor is harmful and may cause heart irregularities, unconsciousness, or death. Intentional misuse can be fatal. Vapor is heavier than air and reduces the amount of oxygen available for breathing. Product causes eye and skin irritation. Decomposition products are hazardous.
DO NOT USE OXYGEN to purge lines or to pressurize a machine for any purpose. Oxygen gas reacts violently with oil, grease, and other common substances.
DO NOT USE air to leak test. Use only refrigerant or dry nitrogen. NEVER EXCEED specified test pressures. VERIFY the allowable test pressure by checking the instruction literature and the design pressures on the equipment nameplate.
DO NOT VALVE OFF any safety device.
BE SURE that all pressure relief devices are properly installed and functioning before operating any machine.
RISK OF INJURY OR DEATH by electrocution. High voltage is present on motor leads even though the motor is not running. Open the power supply disconnect before touching motor leads or terminals.
DO NOT WELD OR FLAMECUT any refrigerant line or vessel until all refrigerant (liquid and vapor) has been removed from chiller. Traces of vapor should be displaced with dry air or nitrogen and the work area should be well ventilated. Refrigerant in contact with an open flame produces toxic gases.
DO NOT USE eyebolts or eyebolt holes to rig heat exchangers or the entire assembly.
DO NOT work on high-voltage equipment unless you are a qualified electrician.
DO NOT WORK ON electrical components, including control panels, switches, starters, or oil heater until you are sure ALL POWER IS OFF and no residual voltage can leak from capacitors or solid-state components.
LOCK OPEN AND TAG electrical circuits during servicing. IF WORK IS INTERRUPTED, confirm that all circuits are deenergized before resuming work.
AVOID SPILLING liquid refrigerant on skin or getting it into the eyes. USE SAFETY GOGGLES. Wash any spills from the skin with soap and water. If liquid refrigerant enters the eyes, IMMEDIATELY FLUSH EYES with water and consult a physician.
NEVER APPLY an open flame or live steam to a refrigerant cylinder. Dangerous over pressure can result. When it is necessary to heat refrigerant, use only warm (110 F [43 C]) water.
DO NOT REUSE disposable (nonreturnable) cylinders or attempt to refill them. It is DANGEROUS AND ILLEGAL. When cylinder is emptied, evacuate remaining gas pressure, loosen the collar, and unscrew and discard the valve stem. DO NOT INCINERATE.
CHECK THE REFRIGERANT TYPE before adding refrigerant to the machine. The introduction of the wrong refrigerant can cause machine damage or malfunction.
Operation of this equipment with refrigerants other than those cited herein should comply with ANSI/ASHRAE 15 (latest edition). Contact Carrier for further information on use of this machine with other refrigerants.
DO NOT ATTEMPT TO REMOVE fittings, covers, etc., while machine is under pressure or while machine is running. Be sure pres- sure is at 0 psig (0 kPa) before breaking any refrigerant connection.
CAREFULLY INSPECT all relief valves, rupture discs, and other relief devices AT LEAST ONCE A YEAR. If machine operates in a corrosive atmosphere, inspect the devices at more frequent intervals.
DO NOT ATTEMPT TO REPAIR OR RECONDITION any relief valve when corrosion or build-up of foreign material (rust, dirt, scale, etc.) is found within the valve body or mechanism. Replace the valve.
DO NOT install relief devices in series or backwards.
USE CARE when working near or in line with a compressed spring. Sudden release of the spring can cause it and objects in its path to act as projectiles.
DO NOT STEP on refrigerant lines. Broken lines can whip about and release refrigerant, causing personal injury.
DO NOT climb over a machine. Use platform, catwalk, or staging. Follow safe practices when using ladders.
USE MECHANICAL EQUIPMENT (crane, hoist, etc.) to lift or move inspection covers or other heavy components. Even if compo- nents are light, use mechanical equipment when there is a risk of slipping or losing your balance.
BE AWARE that certain automatic start arrangements CAN ENGAGE THE STARTER, TOWER FAN, OR PUMPS. Open the disconnect ahead of the starter, tower fan, and pumps. Shut off the machine or pump before servicing equipment.
USE only repaired or replacement parts that meet the code require- ments of the original equipment.
DO NOT VENT OR DRAIN waterboxes containing industrial brines, liquid, gases, or semisolids without the permission of your process control group.
DO NOT LOOSEN waterbox cover bolts until the waterbox has been completely drained.
DOUBLE-CHECK that coupling nut wrenches, dial indicators, or other items have been removed before rotating any shafts.
DO NOT LOOSEN a packing gland nut before checking that the nut has a positive thread engagement.
PERIODICALLY INSPECT all valves, fittings, and piping for corro- sion, rust, leaks, or damage.
PROVIDE A DRAIN connection in the vent line near each pressure relief device to prevent a build-up of condensate or rain water.
