VRV VRF System Pipe Sizing

What you'll learn
Basic of VRV/VRF System
VRV Equipment Selection
Pipe Sizing Manual
Pipe Sizing Software
Requirements
Basic Knowledge of HVAC
Description
Course Title:VRF / VRV System Design and Pipe Sizing (Daikin)Module 1 - IntroductionVRF (Variable Refrigerant Flow) definitionVRV (Variable Refrigerant Volume) definitionTerminology difference (VRV patented by Daikin)Applications & benefitsOne outdoor can connect >60 indoor unitsModule 2 - Components & RefrigerantsCompressorsigital Scroll CompressorInverter Scroll CompressorRefrigerants: R-410A, R-407C, R-32, R-454BVFD (Variable Frequency Drive) operationPower frequency relation to compressor speedModule 3 - System TypesCooling Only VRFVariable speed scroll compressorElectronic Expansion Valve (EEV)Heat Pump VRFCooling or heating (not simultaneous)Uses 4-way Reversion Valve & NRVHeat Recovery VRF3-pipe systemCooling & heating simultaneouslyModule 4 - Capacity & Piping LimitsCapacity range: 3 TR to 42 TR (10 kW to 150 kW)Max piping length (Daikin example):150 m same level50 m ODU above IDU40 m ODU below IDUDaikin pipe sizing conditions:Max total length = 1000 mMax equivalent length = 190 mMax 13 m branch to last ODUMax 90 m from first indoor branch to farthest IDUMax level difference ODU-IDU = 90 mMax level difference IDUs = 30 mMax level difference ODUs = 5 mModule 5 - Diversity FactorConcept in VRF designNot all IDUs run at full load simultaneouslyExample: 20 HP total indoor load with 15 HP ODUModule 6 - Design Process (Daikin Example)1. Collect project requirements - building survey2. Perform heat load calculation (E-20 Excel, HAP)3. Select indoor units (IDUs)4. Select outdoor unit (ODU)5. Design refrigerant piping layout in AutoCAD6. Perform pipe sizing (manual or software)Module 7 - Pipe Sizing BasicsPurpose:Ensure correct refrigerant flowAvoid oil return issuesMaintain performance & efficiencyPipes: liquid, gas (suction), discharge (heat recovery)Refnet joints/Y-branch connectorsPipe sizing rules:Size increases after each branchDifferent for horizontal/verticalLong run adjustments (>40 m) require 1-step larger pipeModule 8 - Manual Pipe Sizing Steps (Daikin)1. Verify pipe conditions2. Find CI of indoor units & update on Refnet3. Size pipe between Refnet & IDU (Table 5)4. Size pipe from ODU to first Refnet (Table 9 or 10)5. Size pipe between Refnet to Refnet (Table 6 or 7)6. Select outdoor branch kit (Table 4)7. First Refnet from branch kit (Table 3)8. All other Refnet updates (Table 2)Module 9 - Common Issues from Wrong Pipe SizingPoor cooling/heatingOil return failure → compressor damageRefrigerant pressure drop → efficiency lossSystem alarms/trips
Who this course is for
Mechanical, Electrical, Engineers, Architect
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