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Air Conditioner Accessories Guide

Air Conditioner Pair Coil/Copper Pipe Sizing Chart for Split System

Air Conditioner Pair Coil/Copper Pipe Sizing Chart for Split System

Table of Contents

  • Introduction
  • Common Copper Pipe Sizes
    • Mitsubishi Heavy Industries
    • Mitsubishi Electric
    • Fujitsu
    • Midea
    • GREE
    • Daikin
    • Panasonic
    • Kelvinator
    • Toshiba
    • Samsung
    • LG
    • Hisense
    • Teco
    • Carrier
    • Westinghouse
    • Rinnai

*Please seek professionals for Air Conditioning installation. Please do not DIY. 

The right pair coil size for a split system depends on the unit's capacity. As a general guide, smaller systems (around 2.0 to 2.6kW) use 1/4" and 3/8" pipe, mid-size systems (3.5 to 5.0kW) use 1/4" and 1/2", and larger systems (6.0kW and above) use 3/8" and 5/8". Always match the pipe to the connection sizes specified by your air conditioner manufacturer, as using the wrong size can affect performance and efficiency.

There are 5 common sizes of copper pipes. See table:

Ø Diameter (in inches)  Ø Diameter (in mm)
1/4'' 6.35  mm
3/8'' 9.52  mm
1/2'' 12.70 mm
5/8'' 15.88 mm
3/4'' 19.05 mm

 

We have listed some popular brands Split System as below:

Please note: Check the latest brochures on each brand's official website for up-to-date refrigerant piping info.

Shop our Pair coil range ←

Mitsubishi Heavy Industries- Avanti / Bronte Series:

Model Number Capacity Pair coil sizes
SRK17ZMP-S / DXK05Z5-S 1.7kw 1/4'' 3/8''
SRK20ZSA-W / DXK06ZSA-W 2.0kw 1/4'' 3/8''
SRK2ZSA-W / DXK09ZSA-W 2.5kw 1/4'' 3/8''
SRK35ZSA-W / DXK12ZSA-W 3.5kw 1/4'' 3/8''
SRK50ZSA-W / DXK18ZSA-W 5.0kw 1/4'' 1/2''
SRK63ZRA-W / DXK21ZRA-W 6.3kw 1/4'' 1/2''
SRK71ZRA-W / DXK24ZRA-W 7.1kw 1/4'' 5/8''
SRK80ZRA-W / DXK28ZRA-W 8.0kw 1/4'' 5/8''
SRK95ZRA-W / DXK33ZRA-W 9.5kw 3/8'' 5/8''

 

Mitsubishi Heavy Industries- Avanti Plus Series:

Model Number Capacity Pair coil sizes
SRK20ZSXA-W 2.0kw 1/4'' 3/8''
SRK25ZSXA-W 2.5kw 1/4'' 3/8''
SRK35ZSXA-W 3.5kw 1/4'' 3/8''
SRK50ZSXA-W 5.0kw 1/4'' 1/2''
SRK60ZSXA-W 6.0kw 1/4'' 1/2''

 

Mitsubishi Heavy Industries- Ciara Series:

Model Number Capacity Pair coil sizes
DXK05ZTLA-WF 1.5kw 1/4'' 3/8''
DXK07ZTLA-WF 2.0kw 1/4'' 3/8''
DXK09ZTLA-WF 2.5kw 1/4'' 3/8''
DXK12ZTLA-WF 3.3kw 1/4'' 3/8''
DXK18ZTLA-WF 5.0kw 1/4'' 1/2''
DXK21ZTLA-WF 6.3kw 1/4'' 1/2''
DXK24ZTLA-WF 7.1kw 1/4'' 1/2''

 

Mitsubishi Electric:

Model Number Capacity Pair coil sizes
MSZ-AP20VGD-A1 2.0 kw 1/4"  3/8"
MSZ-AP25VGD-A1 2.5 kw 1/4"  3/8"
MSZ-AP35VGD-A1 3.5 kw 1/4"  3/8"
MSZ-AP42VGD-A1 4.0 kw 1/4"  3/8"
MSZ-AP50VGD-A1 5.0 kw 1/4''  1/2''
MSZ-AP60VGD-A1 6.0 kw 1/4''  1/2''
MSZ-AP71VGD-A1 7.1 kw 1/4''  1/2''
MSZ-AP80VGD-A1 8.0 kw 1/4''  1/2''
MSZ-AS90VGD-A1 9.0 kw 1/4''  1/2''

  

Fujitsu - Lifestyle Next Series:

Model Number Capacity  Pair coil sizes
ASTH09KMTD-NXT 2.5 kw 1/4"  3/8"
ASTH12KMTD-NXT 3.5 kw 1/4"  3/8"
ASTH18KMTD-NXT 5.0 kw 1/4''  1/2''
ASTH22KMTD-NXT 6.0 kw 1/4''  1/2''
ASTH24KMTD-NXT 7.1 kw 1/4''  1/2''
ASTH30KMTD-NXT 8.5 kw 3/8''  5/8''
ASTH34KMTD-NXT 9.5 kw 3/8''  5/8''

 

Fujitsu - Lifestyle Range:

Model Number Capacity  Pair coil sizes
ASTG09KMTC 2.5 kw 1/4"  3/8"
ASTG12KMTC 3.5 kw 1/4"  3/8"
ASTG18KMTC 5.0 kw 1/4''  1/2''
ASTG22KMTC 6.0 kw 1/4''  1/2''
ASTG24KMTC 7.0 kw 1/4''  1/2''
ASTG30KMTC 8.5 kw 3/8''  5/8''
ASTG34KMTC 9.5 kw 3/8''  5/8''

 

Fujitsu - Comfort Series:

Model Number Capacity Pair coil sizes
ASTH09KNCA 2.5 kw 1/4"  3/8"
ASTH12KNCA 3.4 kw 1/4"  3/8"
ASTH14KNCA 4.2 kw 1/4''  1/2''
ASTH18KNTA 5.0 kw 1/4''  1/2''
ASTH22KNTA 6.0 kw 1/4''  1/2''
ASTH24KNTA 7.1 kw 1/4''  1/2''
ASTH30KNTA 8.5 kw 3/8''  5/8''
ASTH34KNTA 9.5 kw 3/8''  5/8''

 

Fujitsu - Classic Series:

Model Number Capacity Pair coil sizes
ASTG09LVCC 2.5 kw 1/4"  3/8"
ASTG12LVCC 3.5 kw 1/4"  3/8"
ASTG18LVCC 5.0 kw 1/4''  1/2''
ASTG22LVCC 6.3 kw 1/4''  5/8''
ASTG24LFCC 7.1 kw 1/4''  5/8''
ASTG30LFCC 8.0 kw 3/8''  5/8''
ASTG34LFCC 9.2 kw 3/8''  5/8''

 

Midea - Apollo Series:

Model Number Capacity Pair coil sizes
MFAB-20NC 2.0 kw 1/4"  3/8"
MFAB26NB/WB 2.6 kw 1/4"  3/8"
MFAB35NB/WB 3.5 kw 1/4''  1/2''
MFAB50NB/WB 5.0 kw 1/4''  1/2''
MFAB70NB/WB 7.0 kw 3/8''  5/8''
MFAB90NB/WB 9.0 kw 3/8''  5/8''

 

MIDEA - Gaia Series:

Model Number Capacity Pair coil sizes
MFCA26VA-N 2.6 kw 1/4" 3/8"
MFCA35VA-N 3.5 kw 1/4" 3/8"

 

Midea - Venus Series:

Model Number Capacity Pair coil sizes
MFAG20VA-N/W 2.0 kw 1/4"  3/8"
MFAG26VA-N/W 2.6 kw 1/4"  3/8"
MFAG35VA-N/W 3.5 kw 1/4"  3/8"
MFAG50VA-N/W 5.0 kw 1/4''  1/2''
MFAG60VA-N/W 6.0 kw 1/4''  1/2''
MFAG70VA-N/W 7.0 kw 1/4''  5/8''
MFAG80VA-N/W 8.0 kw 1/4''  5/8''

 

GREE - Bora Series:

Model Number Capacity Pair coil sizes
GWH09AAC-K6DNA1A/I 2.5 kw 1/4"  3/8"
GWH12AAC-K6DNA1F/I 3.4 kw 1/4"  3/8"
GWH18AAD-K6DNA1D/I 5.2 kw 1/4'' 1/2''
GWH24AAE-K6DNA1F/I 7.1 kw 1/4'' 5/8''
GWH32QF- K6DNC8D 9 kw 1/4'' 5/8''

 

GREE - Alto Hi-Wall Series:

Model Number Capacity Pair coil sizes
GWH09ATBXB-K6DNA1C I/O 2.7 kw 1/4"  3/8"
GWH12ATCXB-K6DNA1B I/O 3.5 kw 1/4"  3/8"
GWH18ATDXD-K6DNA1C I/O 5.2 kw 1/4'' 1/2''
GWH24ATEXF-K6DNA1E I/O 7.1 kw 1/4'' 1/2''
GWH28ATEXF -K6DNA1A I/O 8.2 kw 1/4'' 1/2''

 

Daikin - LITE Series:

Model Number Capacity Pair coil sizes
FTXV20WVMA / FTXF20WVMA 2.0 kw 1/4"  3/8"
FTXV25WVMA / FTXF25WVMA 2.5 kw 1/4"  3/8"
FTXV35WVMA / FTXF35WVMA 3.5 kw 1/4"  3/8"
FTXV46WVMA / FTXF46WVMA 4.0 kw 1/4'' 1/2''
FTXF46WVMA 4.6 kw 1/4'' 1/2''
FTXV50WVMA / FTXF50WVMA 5.0 kw 1/4'' 1/2''
FTXV60WVMA 6.0 kw 1/4'' 1/2''
FTXV71WVMA / FTXF71WVMA

7.0 kw

 3/8''  5/8''
FTXV85LVMA 8.5 kw 3/8''  5/8''
FTXV95LVMA 9.5 kw 3/8''  5/8''

 

Panasonic - Z Series / RZ Series:

Model Number Capacity Pair coil sizes
CS-Z25XKR / CS-Z25VKR / CS-RZ25XKRW /CS-RZ25WKR 2.5 kw 1/4"  3/8"
CS-Z35XKR / CS-Z35VKR / CS-RZ35XKRW / CS-RZ35WKR 3.5 kw 1/4"  3/8"
CS-Z42XKR / CS-Z42VKR / CS-RZ42XKRW / CS-RZ42WKR 4.2 kw 1/4'' 1/2''
CS-Z50XKR / CS-Z50VKR / CS-RZ50XKRW / CS-RZ50WKR 5.0 kw 1/4'' 1/2''
CS-Z60XKR / CS-Z60VKR / CS-RZ60XKRW / CS-RZ60WKR 6.0 kw 1/4'' 1/2''
CS-Z71XKR / CS-Z71VKR / CS-RZ71XKRW / CS-RZ71WKR 7.1 kw 1/4'' 5/8''
CS-Z80XKR / CS-Z80VKR / CS-RZ80XKR / CS-RZ80WKR 8.0 kw 1/4'' 5/8''

 

KELVINATOR - Reverse Cycle: 

Model Number Capacity Pair coil sizes
KSD25HWJ 2.5 kw 1/4" 3/8"
KSD35HWJ 3.5 kw 1/4" 1/2"
KSD50HWJ 5.0 kw 1/4'' 1/2''
KSD71HWJ 7.1 kw 3/8'' 5/8''
KSD90HWJ 9.0 kw 3/8'' 5/8''

 

TOSHIBA - Seiya Hi-Wall Split System: 

Model Number Capacity Pair coil sizes
RAS-07E2KV2G-A 2.0 kw 1/4" 3/8"
RAS-10E2KV2G-A 2.5 kw 1/4" 3/8"
RAS-13E2KV2G-A 3.5 kw 1/4" 3/8"
RAS-16E2KV2G-A 4.2 kw 1/4'' 1/2''
RAS-18E2KV2G-A 5.0 kw 1/4'' 1/2''
RAS-22E2KV2G-A 6.0 kw 1/4'' 1/2''
RAS-24E2KV2G-A 7.1 kw 1/4'' 1/2''

 

TOSHIBA - Seiya Classic Hi-Wall Split System: 

Model Number Capacity Pair coil sizes
RAS-07E2KVG-A 2.0 kw 1/4" 3/8"
RAS-10E2KVG-A 2.5 kw 1/4" 3/8"
RAS-13E2KVG-A 3.5 kw 1/4" 3/8"
RAS-16E2KVG-A 4.2 kw 1/4'' 1/2''
RAS-18E2KVG-A 5.0 kw 1/4'' 1/2''
RAS-22E2KVG-A 6.0 kw 1/4'' 1/2''
RAS-24E2KVG-A 7.1 kw 1/4'' 1/2''
RAS-30E2KVG-A 8.0 kw 3/8''  5/8''
RAS-34E2KVG-A 9.0 kw 3/8''  5/8''
RAS-36E2KVG-A 10.0 kw 3/8''  5/8''

 

TOSHIBA - Shorai Edge Inverter Hi-Wall Split System: 

Model Number Capacity Pair coil sizes
RAS-07E2KVSG-A 2.0 kw 1/4" 3/8"
RAS-10E2KV2G-A 2.5 kw 1/4" 3/8"
RAS-13E2KV2G-A 3.5 kw 1/4" 3/8"
RAS-16E2KV2G-A 4.2 kw 1/4'' 1/2''
RAS-18E2KV2G-A 5.0 kw 1/4'' 1/2''
RAS-22E2KV2G-A 6.0 kw 1/4'' 1/2''
RAS-24E2KV2G-A 7.1 kw 1/4'' 1/2''

 

TOSHIBA - Haori Inverter Hi-Wall Split System:

Model Number Capacity Pair coil sizes
RAS-B10E2KVRG-A 2.5 kw 1/4" 3/8"
RAS-B13E2KVRG-A 3.5 kw 1/4" 3/8"
RAS-B16E2KVRG-A 4.6 kw 1/4'' 1/2''

 

SAMSUNG - AI Smart AIRISE WindFree™ Purification System: 

Model Number Capacity Pair coil sizes
AR09BXECNWKNSA 2.5 kw 1/4" 3/8"
AR12BXECNWKNSA 3.5 kw 1/4" 3/8"
AR18BXECNWKNSA 5.0 kw 1/4'' 1/2''
AR24BXECNWKNSA 7.0 kw 1/4'' 5/8''
AR30BXECNWKNSA 8.0 kw 1/4'' 5/8''

 

SAMSUNG - AI Smart GEO WindFree™ Purification System: 

Model Number Capacity Pair coil sizes
AR09BXEABWKNSA 2.5 kw 1/4" 3/8"
AR12BXEABWKNSA 3.5 kw 1/4" 3/8"
AR18BXEABWKNSA 5.0 kw 1/4'' 1/2''
AR24BXEABWKNSA 7.0 kw 1/4'' 5/8''
AR30BXEABWKNSA 8.0 kw 1/4'' 5/8''

 

SAMSUNG - Geo+ Split System, Tri-Care Purification: 

Model Number Capacity Pair coil sizes
AR09BXGYCWKNSA 2.5 kw 1/4" 3/8"
AR12BXGYCWKNSA 3.5 kw 1/4" 3/8"
AR18BXGYCWKNSA 5.0 kw 1/4'' 1/2''
AR24BXGYCWKNSA 6.8 kw 1/4'' 5/8''
AR30BXGYCWKNSA 8.0 kw 1/4'' 5/8''

 

 SAMSUNG - Bedarra Split System, DRED: 

Model Number Capacity Pair coil sizes
AR09AXHQAWKNSA 2.5 kw 1/4" 3/8"
AR12AXHQAWKNSA 3.5 kw 1/4'' 1/2''
AR18AXHQAWKNSA 5.1 kw 1/4'' 1/2''
AR24AXHQAWKNSA 7.1 kw 3/8''  5/8''

 

LG - High Efficiency Reverse Cycle: 

Model Number Capacity Pair coil sizes
WH09SK-18 2.5 kw 1/4" 3/8"
WH12SK-18 3.5 kw 1/4" 3/8"
WH18SL-23 5.0 kw 1/4'' 1/2''
WH21SL-23 6.1 kw 3/8''  5/8''
WH24SL-23 7.1 kw 3/8''  5/8''
WH30SR-18 8.5 kw 3/8''  5/8''
WH34SR-18 9.4 kw 3/8''  5/8''

 

LG - Smart Series: 

Model Number Capacity Pair coil sizes
WH09TWS 2.6 kw 1/4" 3/8"
WH12TWS 3.4 kw 1/4" 3/8"
WH18TWS 4.8 kw 1/4'' 1/2''
WH24TWS 6.3 kw 1/4'' 5/8''

 

Hisense - V Series:

Model Number Capacity Pair coil sizes
HAWV9KRD 2.5 kw 1/4" 3/8"
HAWV12KRD 3.5 kw 1/4" 3/8"
HAWV18KR 5.0 kw 1/4'' 1/2''
HAWV24KR 7.1 kw 3/8'' 5/8''
HAWV28KR 8.0 kw 3/8'' 5/8''

 

Hisense - J Series:

Model Number Capacity Pair coil sizes
HAWJ9KR 2.5 kw 1/4" 3/8"
HAWJ12KR 3.5 kw 1/4" 3/8"
HAWJ18KR 5.0 kw 1/4'' 1/2''
HAWJ24KRP 7.1 kw 1/4'' 1/2''
HAWJ28KR 8.0 kw 3/8'' 5/8''

 

Teco - Platinum 3D Series:

Model Number Capacity Pair coil sizes
TWS26H3DVJT/TSO26H3DVJT 2.6 kw 1/4" 3/8"
TWS35H3DVJT/TSO35H3DVJT 3.5 kw 1/4'' 1/2''
TWS52H3DVJT/TSO52H3DVJT 5.2 kw 1/4'' 1/2''
TWS72H3DVJT/TSO72H3DVJT 7.2 kw 1/4'' 5/8''
TWS88H3DVJT/TSO88H3DVJT 8.8 kw 1/4'' 5/8''

 

Teco - Comfort Series:

Model Number Capacity Pair coil sizes
TWS25HVHT/TSO25HVHT 2.5 kw 1/4" 3/8"
TWS32HVHT/TSO32HVHT 3.2 kw 1/4" 3/8"
TWS52HVHT/TSO52HVHT 5.2 kw 1/4" 3/8"
TWS71HVHT/TSO71HVHT 7.1 kw 1/4'' 5/8''

 

Carrier - Indigo Inverter Hi Wall:

Model Number Capacity Pair coil sizes
42QAG020N8/38QAG020N8 2.0 kw 1/4" 3/8"
42QAG026N8/38QAG026N8 2.6 kw 1/4" 3/8"
42QAG035N8/38QAG035N8 3.5 kw 1/4" 3/8"
42QAG050N8/38QAG050N8 5.0 kw 1/4'' 1/2''
42QAG060N8/38QAG060N8 6.0 kw 1/4'' 1/2''
42QAG070N8/38QAG070N8 7.0 kw 1/4'' 5/8''
42QAG080N8/38QAG080N8 8.0 kw 1/4'' 5/8''

 

Carrier - Allure Plus Inverter Hi Wall:

Model Number Capacity Pair coil sizes
53QHG020N8-1 2.0 kw 1/4" 3/8"
53QHG026N8-1 2.6 kw 1/4" 3/8"
53QHG035N8-1 3.5 kw 1/4" 3/8"
53QHG050N8-1 5.0 kw 1/4'' 1/2''
53QHG060N8-1 6.0 kw 1/4'' 1/2''
53QHG070N8-1 7.0 kw 1/4'' 5/8''
53QHG080N8-1 8.0 kw 1/4'' 5/8''

 

Westinghouse:

Model Number Capacity Pair coil sizes
WSD27HWA 2.7 kw 1/4" 3/8"
WSD36HWA 3.6 kw 1/4" 1/2''
WSD51HWA 5.1 kw 1/4'' 1/2''
WSD73HWA 7.3 kw 1/4'' 5/8''
WSD91HWA 9.1 kw 3/8'' 5/8''

 

Rinnai - J Series:

Model Number Capacity Pair coil sizes
HSNRJ25B1 2.6 kw 1/4" 3/8"
HSNRJ35B1 3.5 kw 1/4" 1/2''
HSNRJ50B1 5.2 kw 1/4'' 1/2''
HSNRJ70B1 7.0 kw 1/4'' 5/8''
HSNRJ80B1 8.0 kw 1/4'' 5/8''

 

Rinnai - PB Series:

Model Number Capacity Pair coil sizes
HSNRP26B 2.6 kw 1/4" 3/8"
HSNRP35B 3.5 kw 1/4" 3/8"
HSNRP50B 5.2 kw 1/4'' 1/2''
HSNRP60B 6.0 kw 1/4'' 1/2''
HSNRP70B 7.0 kw 1/4'' 5/8''
HSNRP80B 8.0 kw 1/4'' 5/8''

 

Rinnai - T Series:

Model Number Capacity Pair coil sizes
HSNRT25B 2.5kw 1/4" 3/8"
HSNRT35B 3.5 kw 1/4" 1/2''
HSNRT50B 5.0 kw 1/4'' 1/2''
HSNRT70B 7.0 kw 1/4'' 5/8''
HSNRT80B 8.0 kw 1/4'' 5/8''

 

References

Daikin Australia. (2023). Split System Installation Guidelines and Piping Specifications. https://www.daikin.com.au/

Mitsubishi Electric. (2023). Technical Data Book – Refrigerant Piping for Wall Mounted Split Systems. https://www.mitsubishielectric.com.au/

ASHRAE. (2023). HVAC Piping and Refrigerant Line Sizing Guidelines. https://www.ashrae.org/

Reference Date: 01/2023

by Nancy Shan

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Frequently Asked Questions
What size copper pipe do I need for a split system?

It depends on the system’s capacity. Smaller units around 2.0 to 2.6kW typically use 1/4" and 3/8" pair coil, mid-size units 1/4" and 1/2", and larger units 3/8" and 5/8". Always confirm against your unit manufacturer’s specified connection sizes.
Can I use a larger pipe size than specified?

No. You should match the pipe size to the manufacturer’s specification. Using the wrong size, larger or smaller, can affect refrigerant flow, performance and efficiency, and may cause installation problems.
What is pair coil?

Pair coil is a matched pair of pre-insulated copper tubes that carry refrigerant between the indoor and outdoor units of a split system. It combines the gas and liquid lines with insulation in one convenient product.
Where can I buy the right size pair coil?

Star Sparky stocks pre-insulated copper pair coil in all the common sizes, ready for R32 and R410A systems. Match the size to your unit using the chart above, then shop the pair coil range.