Carrier AQUAZONE 50KQE Series Installation, Operation And Maintenance Instructions

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Carrier AQUAZONE 50KQE Series Installation, Operation And Maintenance Instructions Manual pdf 19 page image

194 - PRE-START-UP4.1 - System cleaning and flushingCleaning and flushing the unit and system is the single mostimportant step to ensure proper start-up and continued efficientoperation of the system.WARNING: To prevent injury or death due to electricalshock or contact with moving parts, open unit disconnectbefore servicing the unit.Follow the instructions below to clean and flush the systemproperly:CAUTION: Do not flush system through the unit!1. Verify that electrical power to the units is disconnected,and that the circulation pump is deenergized.2. Connect the supply hose directly to the return riser valve.Use a single length of flexible hose, as shown in Fig. 17.NOTE: If the length of hose is too short (i.e., the resultingconnection would exceed the minimum bend radius of thehose), substitute two lengths of flexible hose joined togetherwith a field-supplied, standard NPT coupling and the flare-fitting-to-pipe adapters provided with the hose kit (Fig. 17).Fig. 17 - Temporary connection for flushing systempiping7. Open a drain at the lowest point in the system. Adjust themake-up water replacement rate to equal the rate of bleed.Continue to bleed the system until the water appears cleanor for at least three hours, whichever is longest; then, com-pletely drain the system.8. Refill the system with clean, chemically treated water.Since water varies for each locality, contact a local watertreatment company for the correct treatment chemicals touse in your area. Set the boiler to raise the looptemperature to approximately 29∞C.CAUTION: To avoid possible damage to piping systems con-structed of plastic piping DO NOT allow loop temperature toexceed 43∞C.Circulate the solution for a minimum of 8 to 24 hours. Atthe end of this period, shut off the circulating pump anddrain the solution. Repeat system cleaning as necessary.9. When the cleaning process is complete, remove the short-circuited hoses. Connect the hoses to the proper supplyand return connections on each unit. Refill the system andbleed off all air.10. Test the system pH with litmus paper. The system watershould be slightly alkaline (pH 7.5 to 8.5). Add chemicals,as appropriate, to maintain acidity levels.CAUTION: DO NOT use “Stop-Leak” or any similar chemicalagent in this system. Addition of these chemicals to the loopwater will foul the system and will inhibit unit operation.11. When the system is successfully cleaned, flushed, refilledand bled, check the main system panels, safety cutouts andalarms. Set the controls to properly maintain loop tempera-tures.4.2 - System checkoutWhen the installation is complete and the system is cleaned andflushed, follow the System Checkout procedure outlined below.1. Voltage: Ensure voltage is within the utilisation rangespecifications of the unit compressor and fan motor.2. System water temperature: Ensure temperature is withinan acceptable range shown in Table 4. (When conductingthis check, also verify proper heating and cooling set points.)3. System water pH: Verify system water is slightly alkaline(pH = 7.5 to 8.5). Proper pH promotes the longevity of thehoses and heat exchangers (see Table 5).4. Closed-type cooling tower (open tower with heat exchanger):Check equipment for proper temperature set points andoperation.5. Balanced water flow rate to heat pump: Record the inletand outlet water temperatures as each heat pump unit isstarted. This check will eliminate nuisance unit tripoutsresulting from water velocities that are either too low ortoo high; it can also prevent erosive water flow rates.6. Standby pump: Verify the standby pump is properlyinstalled and in operating condition.7. System control: To ensure no catastrophic system failuresoccur, verify system controls are functioning and thesequencing is correct.8. Freeze protection for water systems: Verify freeze protec-tion is provided for the outdoor portion of the loop watersystem. Inadequate freeze protection leads to expensiverepairs.1/2” Flexible HoseBrass Adapter(1/2” MPT x 1/2”Male Flare)Supply ValveFloor LineReturn Valve1/2” flexible hoseSupply valveFloor lineBrass adapter(1/2” MPT x 1/2”male flare)Return valveNote: Use standard coupling (field-supplied) and hose adapters to join 2 hoses.3. Open all air vents. Fill the system with water. Do not allowsystem to overflow. Bleed all air from the system. Checkthe system for leaks and repair appropriately.4. Check and adjust the water and air level in the expansion tank.5. Verify all strainers are in place. Start the pumps, and sys-tematically check each vent to ensure all air is bled fromthe system.6. Verify make-up water is available. Adjust make-up waterappropriately to replace the air that was bled from thesystem. Pressure test and inspect the system for leaks andmake any necessary repairs. Check and adjust the waterand air level in the expansion tank.