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VRV III Product Selection Piping selection. Selection Considerations. Cooling Load calculations Heating Load calculations Internal and Ambient temp Building layout drawings Orientation Room Usage Fresh Air Requirements Air and temperature distribution. Noise Levels Pipe Runs
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Selection Considerations • Cooling Load calculations • Heating Load calculations • Internal and Ambient temp • Building layout drawings • Orientation • Room Usage • Fresh Air Requirements • Air and temperature distribution • Noise Levels • Pipe Runs • Unit Dimensions • Aesthetics • Planning Restrictions • Possible future site expansion Total or sensible capacity selection ?
Outdoor and Indoor Unit selection is based on using the capacity index To select indoor unit and unit combinations, to size pipe work and refnet joints, we use ‘Index’ numbers: For example the index no of FXZQ20M7V1B is 20
Maximum Number of Indoor Units Connected to One Outdoor Unit
Maximum Number of Indoor Units Connected to BS Boxes (required for Heat Recovery Systems)
Indoor unit Selection FXCQ Based on High Fan Speed For “Low Fan” Speed, capacity reduction is not published, but the correction factors from next slide may be used.
Indoor Unit Selection Select indoor units for room layout provided “Example (FXCQ) of where information can be found” Starting from Engineering data book EEDE06-2 page 795: Noise Levels details Engineering data book EEDE06-2 page 815 Unit Dimensions Engineering data book EEDE06-2 page 798 Air Distribution Engineering data book EEDE06-2 page 818 Make a record of Model, Fan speed, Total and Sensible Cooling duties
Indoor Unit Selection 18 m Room A 8.0kw Sensible Cooling N 6 m 3 m 3 m Room E 1.65 kw Sensible Room D 2.5 kw Sensible Room C 2.1 kw Sensible Room B 4.2 kw Sensible 3 m 6 m Room A - General Office Room B - Meeting Room Room C - Manager Room D - Small office Room E - Reception 6 m 3 m Rooms A, B and E 400mm ceiling void Room C 200 mm ceiling void Room D no void (restricted floor space) Ceiling Height 2.7m Internal design 23 deg C db 16 deg C wb Ambient design 29 deg C db
Indoor Unit Selection Possible Solution Internal design 23 deg C db 16 deg C wb Ambient design 29 deg C db Note: The low speed duties were calculated based on the correction factors shown in the previous table.
Condensing Unit Selection Considerations • Remember the maximum index connectable • Remember the maximum number of indoor units • Cooling Only, Heat Pump or Heat Recovery • Positioning • Noise levels • Service Access space required
Condensing Unit Selection 18 m Room A 6 m FXFQ40M FXFQ40M FXFQ40M Room E Room D Room C Room B 3 m FXAQ40M FXSQ32M 6 m FXSQ80M FXLQ40M Condensing Unit Base 3 m 6 m
Condensing Unit Selection Example: using Inverter 2 pipe Heat Pump Room A 3 x FXFQ40M 120 Room B 1 x FXSQ80M 80 Room C 1 x FXLQ40M 40 Room D 1 x FXAQ40M 40 Room E 1 x FXSQ32M 31.25 Total Index 311.25 Suitable Condensing Unit RXYQ10P7W1 Indoor Unit Combination Index Outdoor Unit Minimum Maximum 162.5 260 325 RXYQ5P7W1 RXYQ8P7W1/REYQ8M RXYQ10P7W1/REYQ10M 62.5 100 125
27.0 kW – 1.944 kW = 25.055 kW Condensing Unit Selection Example: using Inverter 2 pipe heat pump Room A 3 x FXFQ40M 120 Room B 1 x FXSQ80M 80 Room C 1 x FXLQ40M 40 Room D 1 x FXAQ40M 40 Room E 1 x FXSQ32M 31.25 Total Index 311.25 Suitable Condensing Unit RXYQ10P7W1 Look up condensing unit duty from EEDE06–2 page 196 At indoor temperature of 16 deg C wb and outdoor temp 29 deg C db Total Cooling with index of 308 = 24,8 kW Total Cooling at index of 336 = 27.0 kW Index connected = 336 – 311.25 = 24.75 27,0 kW – 24,8 = 2.2 kW 336 – 308 = 28 2.2 kW/28 = 0.0785 kW 24.75 x 0.0785 = 1.944 kW
Condensing Unit Selection Example: using Inverter 2 pipe heat pump (Back to the original data selected at high speed) Calculate corrected indoor unit capacity RXYQ10M total cooling = 25.05kW FXFQ40M = (40 x 25.05) = 3.22 kW total 311. 25 Reduce sensible by the same proportion prior to correction calculation Don’t forget to apply correction for low speed when necessary: FXSQ80 = (80 x 25.05) x 0.87 = 5,60 kW total 311.25 FXSQ80 = 4.73 x 5,60 = 4.44 kW sensible 5.97
Condensing Unit Selection Example: using Inverter 2 pipe heat pump Not yet ? Are we finished ?
Pipe Length Correction Example: using Inverter 2 pipe heat pump Look up capacity correction ratio on page 294 of EEDE06-2 Table RXYQ10P For Room B FXSQ80M Run = 20m Level difference = Outdoor unit 3m below indoor unit Capacity reduction factor = 0.98
Pipe Length Correction 18 m Room A 6 m FXFQ40M FXFQ40M FXFQ40M Room E Room D Room C Room B 3 m FXAQ40M FXSQ32M 6 m FXSQ80M FXLQ40M Condensing Unit Base 3 m 6 m
(Change in Cooling Capacity) Pipe Length Correction (H=m) 0.90 0.87 0.85 50 Outdoor situated above Indoor units 0.92 40 0.95 30 0.98 20 1.0 10 0 10 20 30 40 50 60 70 80 90 100 110 ……..190 m 0 Example: 0 Outdoor unit 3m below Indoor unit 10 1.0 20 0.98 30 Outdoor situated below Indoor units 40 0.95 0.92 0.90 0.87 0.85 (H=m)
Pipe Length Correction Example: using Inverter 2 pipe heat pump
Additional correction due to Defrost operation Defrost operation protects the outdoor unit coil against freezing: • Happens in heating mode • Performs oncemaxevery 2 hours • Duration: between 4 and 8 min • During defrost: outdoor/indoor units’ fans are stopped • No heating is delivered during defrost • Limited cooling is delivered (heat recovery models) • Capacity tables do not take account of this capacity reduction • The heating capacity should be ammended by a correction factor:
Summary of selection after corrections Example: using Inverter 2 pipe heat pump Required sensible Result total Result sensible If selected fan coil unit corrected duty is too low, then that unit has to be re-selected and the complete procedure repeated
Would this suit Heat Recovery? Room A FXFQ40M FXFQ40M FXFQ40M Room E Room D Room C Room B FXAQ40M FXSQ32M FXSQ80M FXLQ40M Meeting Room
VRVII Heat Recovery: selection of BS Boxes Room A FXFQ40M FXFQ40M FXFQ40M Room E Room D Room C Room B FXAQ40M FXSQ32M Condensing Unit Base with REYQ10M FXSQ80M FXLQ40M BS Box
VRV Selection Software VRV Express
VRV Express Material list
VRV Express Indoor unit details
VRV refrigerant piping system is based on REFNETS Advantages of REFNET system: Short dimensioning time Short installation time REFNET joint REFNET header NEVER install a joint after a header !
+ 30° Refnet installation recommendations Joints are to be mounted …. Vertically …..Horizontally
Possibly match pipe and refnet using adaptors prototypes REFNET piping system Select refnets according to the capacity Adjust the pipe size according to the capacity
Refrigerant Pipe Work Maximum “Actual” Piping Limitations A Can become 90 m in certain conditions A • For level differences • above 50m; • One size up of • main liquid pipe • Option kit 40M 15M 90M 165M • Total piping length = 1000M • No Oil traps • No Liquid traps • No Solenoid valves • No Sight glasses • No Driers • No Additional oil • Max pressure test 38.5 bar 190M Max EQUIVALENT LENGTH
Field Piping Limitations VRV III P series (Heat pump Inverter) • “Longest” – “shortest” branch = b+c+d+e+l-f <=40m • f, g,h, j, k, l, m, n <= 40m • Pipes b, c, d, e between first and last kit are sized up • For the total piping calculation the actual length of b, c, d, e is counted double if 90m RXYQ…P Can be 40m 165m a b c d e 90m NEVER INSTALL A JOINT AFTER A HEADER j k f h g l n m FXSQ….M FXAQ….M FXHQ….M FXCQ….M FXCQ….M 15m FXLQ….M FXLQ….M FXLQ….M
VRVII “M” Series Field Piping Limitations (Heat Recovery) REYQ….M 150m 40M 50m BSVQ. .M BSVQ. .M BSVQ. .M BSVQ. .M BSVQ. .M BSVQ. .M BSVQ. .M FXSQ….M FXHQ….M FXCQ….M FXCQ….M BSVQ. .M BSVQ. .M 15m FXLQ….M FXLQ….M FXLQ….M FXLQ….M FXLQ….M
Piping joints required at the first branch VRV III VRV II H/R
Piping Joints other than the first branch VRV III VRV II H/R
Possibly, this results into a bigger joint than the 1st joint ! Do NOT increase the size ! Selection of Piping Joints 1st joint corresponds to outdoor unit 2nd Joint according to class total
Piping Headers PLEASE NOTE : Class 250 CANNOT be connected to a header
Pipe Sizing between refnet branch kits for heat pump models Piping Adjust the pipe size according to the capacity Possibly, this results into a bigger pipe than the one coming from the outdoor unit ! Do NOT increase the size !
Refrigerant pipe Size Connections to Indoor Units The pipe size of the indoor unit Please note: all the above connections are flared other than the gas pipe connection on the 200 an 250 models being brazed style
Pipe Size connections to the outdoor units for Heat recovery Pipe Sizing between refnet branch kits for Heat recovery
Equivalent length = a reference for a pressure drop of an component in the pipe work = length of linear pipes + allowances for fittings The following allowances should be allocated to the following components: Overall Equivalent length = =(Equivalent length of main pipe work x 0.5) + Equivalent length of branch pipe work
Increase only gas for ! RX(Y)Q5P7 Increase only liquid for RXYQ12,14,24, 36~54 P The WHOLE RANGE REYQ : What happens when the overall equivalent length from the condensing unit to any indoor unit exceeds 90 m ? Increase diameter of the Liquid AND theGas pipes between the condenser and the first refnet BUT !