Carrier AquaForce PUREtec 30XW-VZE 451 Installation, Operation And Maintenance Instructions

5Never cover any protection devices.This applies to the relief valves in the refrigerant or heat transfermedium circuits, and the pressure switches.Ensure that the valves are correctly installed, before operating theunit.DO NOT OBSTRUCT ANY PROTECTIVE DEVICES:This applies to any fusible plugs, rupture disks and valves fittedon the refrigerant or heat transfer fluid circuits. Check whether theoriginal protection plugs are still present at the valve outlets. Theseplugs are generally made of plastic and should not be used. If theyare still present, please remove them. Fit devices at the valve ordischarge piping outlets to prevent the penetration of foreignbodies (dust, building debris, etc.) and atmospheric agents (watercan form rust or ice). These devices, as well as the dischargepiping, must not impair operation or lead to a pressure drop thatis higher than 10% of the set pressure.CLASSIFICATION AND CONTROL:In accordance with the Pressure Equipment Directive and nationalusage monitoring regulations in the European Union, the protectivedevices fitted to these machines are classified as follows:Safetydevice(1)Device for damagelimitation in the event of anexternal fire(2)Refrigerant SideHigh pressure safety loop (3) XExternal relief valve (4) XRupture disk XHeat transfer fuid sideExternal relief valve (5) (5)(1) Classified for protection in normal service situations.(2) Classified for protection in abnormal service situations. These accessories aresized for fires with a thermal flow of 10kW/m². No combustible matter should beplaced within 6.5m of the unit.(3) High pressure safety loop = SRMCR as described in component section of thismanual and in electrical diagram.(4) The instantaneous overpressure limitation of 10% of the operating pressuredoes not apply to this abnormal service situation.The control pressure can be higher than the service pressure. In this case, eitherthe design temperature or the high pressure switch ensures that the servicepressure is not exceeded in normal service situations.(5) The selection of these relief valves must be made by the personnel responsiblefor completing the hydraulic installation.All factory-installed relief valves are lead-sealed to prevent canycalibration change. The external relief valves must always bevented to outside if the units are installed in a closed space. Referto the installation regulations, for example those of Europeanstandard EN 378 and EN 13136. These pipes must be installedin a way that ensures that people and property are not exposedto vented refrigerant. As the fluids can be diffused in the air, ensurethat refrigerant is discharged away from building air intakes, reliefvalves must be checked periodically. The valves must be checkedperiodically.The safety device shall be tested at least once a year to verifygood operation and cut out value.An example of test procedure without removing the pressureswitch is given in Section 13.8 of this manual.If the relief valves are installed on a change-over manifold, this isequipped with a relief valve on each of the two outlets. Only oneof the two relief valves is in operation, the other one is isolated.Never leave the change-over valve in the intermediate position,i.e. with both ways open (locate the control element in the stopposition). If a relief valve is removed for checking or replacementplease ensure that there is always an active relief valve on eachof the change-over valves installed in the unit.All factory-installed relief valves are lead-sealed to prevent anycalibration change.The external relief valves are designed and installed to ensuredamage limitation in case of a fire.In accordance with the regulations applied for the design, theEuropean directive on equipment under pressure and inaccordance with the national usage regulations:- These relief valves (and rupture disk if used) are not safetyaccessories but damage limitation accessories in case of afire,- The high pressure switches are the safety accessories.The relief valve must only be removed if the fire risk is fullycontrolled and after checking that this is allowed by localregulations and authorities. This is the responsibility of theoperator.When the unit is subjected to fire, safety devices prevent rupturedue to over-pressure by releasing refrigerant. The fluid may thenbe decomposed into toxic residues when subjected to the flame:- Stay away from the unit- Set up warnings and recommendations for personnel incharge to stop the fire.- Fire extinguishers appropriate to the system and therefrigerant type must be easily accessible.The external relief valves must be connected to discharge pipesfor units installed in a room. Refer to the installation regulations,for example those of European standards EN-378.These standards include a sizing method and examples forconfiguration and calculation. Under certain conditions they permitconnection of several valves to the same discharge pipe.Carrier recommends using flexible hose to connect the relief valvesto discharge pipe. Special care shall be taken so that coupling todischarge pipe is not creating mechanical stress on relief valveconnection.These pipes must be installed in a way that ensures that peopleand property are not exposed to refrigerant leaks. These fluidsmay be diffused in the air, but far away from any building air intake,or they must be discharged in a quantity that is appropriate for asuitably absorbing environment (Note that the R1234ze(E) andR515B refrigerants are heavier than air).It is recommended to install an indicating device to show if part ofthe refrigerant has leaked from the valve. The presence of oil atthe outlet orifice is a useful indicator that refrigerant has leaked.Keep this orifice clean to ensure that any leaks are obvious.The calibration of a valve that has leaked is generally lower thanits original calibration. The new calibration may affect the operatingrange. To avoid a nuisance tripping or leaks, replace or re-calibratethe valve.Periodic check of the relief valves: See paragraph “Maintenancesafety considerations”.Provide a drain in the discharge circuit, close to each relief valve,to avoid an accumulation of condensate or rain water.Ensure good ventilation, as accumulation of refrigerant in anenclosed space can displace oxygen and cause asphyxiation orexplosions.Inhalation of high concentrations of vapour is harmful and maycause heart irregularities, unconsciousness, or death. Vapour isheavier than air and reduces the amount of oxygen available forbreathing. These products cause eye and skin irritation.Decomposition products are hazardous.1 - INTRODUCTION