Daikin Enfinity Installation And Maintenance Manual

Daikin Enfinity Installation And Maintenance Manual Manual pdf 21 page image

IM 1059-12 LARGE VERTICAL WSHP 21 www.DaikinApplied.comCleaning & flushing system1 Prior to first operation of any conditioner, the watercirculating system must be cleaned and flushed ofall construction dirt and debris.If the conditioners are equipped with water shutoffvalves, either electric or pressure operated, the supplyand return run-outs must be connected togetherat each conditioner location. This will prevent theintroduction of dirt into the unit (Figure 15).Figure 15: Supply & return run-outs connected togetherReturn Run-outSupply Run-outMainsFlexibleHose Run-outs InitiallyConnected Together2 Fill the system at the city water makeup connectionwith all air vents open. After filling, close all airvents. The contractor should start main circulatorwith the pressure reducing valve open. Check ventsin sequence to bleed off any trapped air, ensuringcirculation through all components of the system.Power to the heat rejector unit should be off, and thesupplementary heat control set at 80°F (27°C).Whilecirculating water, the contractor should check andrepair any leaks in the piping. Drains at the lowestpoint(s) in the system should be opened for initialflush and blowdown, making sure city water fill valvesare set to make up water at the same rate. Checkthe pressure gauge at pump suction and manuallyadjust the makeup to hold the same positive steadypressure both before and after opening the drainvalves. Flush should continue for at least two hours,or longer if required, to see clear, clean drain water.3 Shut off supplemental heater and circulator pumpand open all drains and vents to completely draindown the system. Short circuited supply and returnrun-outs should now be connected to the conditionersupply and return connections. Do not use sealersat the swivel flare connections of hoses.4 Trisodium phosphate was formerly recommendedas a cleaning agent during flushing. However,many states and localities ban the introduction ofphosphates into their sewage systems. The currentrecommendation is to simply flush longer with warm80°F (27°C) water.5 Refill the system with clean water. Test the waterusing litmus paper for acidity, and treat as requiredto leave the water slightly alkaline (pH 7.5 to 8.5).The specified percentage of antifreeze may also beadded at this time. Use commercial grade antifreezedesigned for HVAC systems only. Do not useautomotive grade antifreeze.Once the system has been filled with clean waterand antifreeze (if used), precautions should be takento protect the system from dirty water conditions.Dirty water will result in system wide degradation ofperformance and solids may clog valves, strainers,flow regulators, etc. Additionally, the heat exchangermay become clogged which reduces compressorservice life or causes premature failure.6 Set the loop water controller heat add setpointto 70°F (21°C) and the heat rejection setpoint to85°F (29°C). Supply power to all motors and startthe circulating pumps. After full flow has beenestablished through all components including theheat rejector (regardless of season) and air ventedand loop temperatures stabilized, each of theconditioners will be ready for check, test and start-up, air balancing, and water balancing.Operating limitsInformation for initial start-up onlyStandard range units:Units are designed to start in an ambient of 50ºF (10ºC),with entering air at 50ºF (10ºC), with entering water at70ºF (21ºC), with both air and water at the flow rates usedin the ISO 13256-1 rating test, for initial start-up in winter.Note: This is not a normal or continuous operatingcondition. It is assumed that such a start-up is forthe purpose of bringing the building space up tooccupancy temperature.Extended range units:Extended range heat pump conditioners are designedto start in an ambient of 40ºF (5ºC), with entering air at40ºF (5ºC), with entering water at 40ºF (5ºC), with bothair and water at the flow rates used in the ISO 13256-1rating test, for initial start-up in winter.Note: This is not a normal or continuous operatingcondition. It is assumed that such a start-up is forthe purpose of bringing the building space up tooccupancy temperature.unit installation