Hitachi Primairy Series - Refrigerant Piping

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Refrigerant piping
1 Piping requirement
Model
Outerdiameterofpipe(mm)
Gas Liquid
3.0/3.5HP 15.88 9.52
4.0/5.0/6.0/6.5HP 19.05 9.52
The shorter the refrigerant piping is, the better the performance will be. So the connecting pipe should be as short as possible.
Indoor unit
Outdoor unit
PipelengthL
Height difference H
(Unit:mm)
Model
Max.pipelength
(L)
Max.height
difference(H)
Add. refrigerant
(exceed5m)
3.0HP 30(m) 15(m) 28(g/m)
3.5/4.0/5.0/
6.0/6.5HP
50(m) 30(m) 28(g/m)
Refrigerant piping between indoor unit and outdoor unit
Oil trap
Slope:1/200~1/250
Slope:1/200~1/250
Oil trap
Refrigerant additional charge
Theunithasbeenlledwithrefrigerant,butifexceeds5m,additionalrefrigerant(R32)chargeisrequired.
Additionalrefrigerantcharge=(L-5)×28g/m
Oil trap
Whentheindoorunitislowerthanoutdoorunitandheightislargerthan5m,setanoiltrapevery5m(heightdifference)onsuction
piping.
NOTE:
• Toavoidstoringtoomuchoilintheoiltrap,theoiltrapshouldbeasshortaspossible.
• Thehorizontalpipingshouldbeslopedownalongtherefrigerantowdirection,tobringtheoilbacktocompressor,theslopeis
about1/200to1/250.
• Inordertoensureabettercooling/heatingperformance,therefrigerantpipingshouldbeasshortandstraightaspossible.
2 Piping material
1. Preparelocally-suppliedcopperpipes.
2. Selectcleancopperpipes.Makesurethatthereisnodustandmoistureinsideofthepipes.Blowtheinsideofthepipeswith
nitrogen or dry air to remove any dust or foreign materials before connecting pipes.
3. Pipingthicknessandmaterialofthepipeareshownbelow.
Unit: mm
Diameter Thickness
∅6.35 0.8
∅9.52 0.8
∅12.7 0.8
∅15.88 1.0
∅19.05 1.0
INSTALLATIONINSTRUCTIONS
HO2019292HA
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