Panasonic EAIRC-MJ Series Installation Instructions Manual

Contents

Panasonic EAIRC-MJ Series Installation Instructions Manual Manual pdf 19 page image

19● For the flare nuts at tubing connections, be sure to use theflare nuts that were supplied with the unit, or else flare nutsfor R410A (type 2). The refrigerant tubing that is used mustbe of the correct wall thickness as shown in the table below.Tube diameter Tightening torque(approximate) Tube thicknessø6.35 (1/4") 14 – 18 N · m(140 – 180 kgf · cm) 0.8 mmø9.52 (3/8") 34 – 42 N · m(340 – 420 kgf · cm) 0.8 mmø12.7 (1/2") 49 – 61 N · m(490 – 610 kgf · cm) 0.8 mmø15.88 (5/8") 68 – 82 N · m(680 – 820 kgf · cm) 1.0 mmø19.05 (3/4") 100 – 120 N · m(1000 – 1200 kgf · cm) 1.0 mmBecause the pressure is approximately 1.6 times higher thanconventional refrigerant pressure, the use of ordinary flarenuts (type 1) or thin-walled tubes may result in tube rupture,injury, or asphyxiation caused by refrigerant leakage.● In order to prevent damage to the flare caused by over-tightening of the flare nuts, use the table above as a guidewhen tightening.● When tightening the flare nut on the liquid tube, use anadjustable wrench with a nominal handle length of 200 mm.5-3. Insulating the Refrigerant TubingTubing Insulation● Thermal insulation must be applied to all units tubing,including distribution joint (field supply).* For gas tubing, the insulation material must be heatresistant to 120°C or above. For other tubing, it must beheat resistant to 80°C or above.Insulation material thickness must be 10 mm or greater.If the conditions inside the ceiling exceed DB 30°C and RH70%, increase the thickness of the gas tubing insulationmaterial by 1 step.Two tubes arranged togetherLiquid tubing Gas tubingInsulationFig. 5-7CAUTIONIf the exterior of the outdoor unit valves has been finishedwith a square duct covering, make sure you allow sufficientspace to access the valves and to allow the panels to beattached and removed.Taping the flare nutsWind the white insulation tape around the flare nuts at the gastube connections. Then cover up the tubing connections withthe flare insulator, and fill the gap at the union with the suppliedblack insulation tape. Finally, fasten the insulator at both endswith the supplied vinyl clamps. (Fig. 5-8)Flare insulator (supplied)Insulation tape (white)(supplied)Tube insulator(not supplied)Heat resistant120°C or aboveFlare unionFlare nutUnit sideFig. 5-8Insulation materialThe material used for insulation must have good insulationcharacteristics, be easy to use, be age resistant, and must noteasily absorb moisture.CAUTIONAfter a tube has been insulated, never try to bend it intoa narrow curve because it can cause the tube to break orcrack.Never grasp the drain or refrigerant connecting outletswhen moving the unit.5-4. Taping the Tubes(1) At this time, the refrigerant tubes (and electrical wiringif local codes permit) should be taped together witharmoring tape in 1 bundle. To prevent condensation fromoverflowing the drain pan, keep the drain hose separatefrom the refrigerant tubing.(2) Wrap the armoring tape from the bottom of the outdoorunit to the top of the tubing where it enters the wall. As youwrap the tubing, overlap half of each previous tape turn.(3) Clamp the tubing bundle to the wall, using 1 clamp approx.each meter. (Fig. 5-9)Insulated tubes Drain hoseClampFig.5-9NOTEDo not wind the armoring tape too tightly since this willdecrease the heat insulation effect. Also ensure that thecondensation drain hose splits away from the bundle and dripsclear of the unit and the tubing.