Nimbus Plus S NET R32 Installation Manual UK

Hydraulic and

Hydraulic and refrigerant connections 4.1.3 Flaring the ends of the pipe – Seal the ends of the pipe (1) using PVC tape to prevent foreign material from penetrating inside. – Wrap the pipe with insulating material. – Fit a flared nut (2) on each end of the pipe. Make sure that the nuts face the right direction, because once the pipe end is flared it will not be possible to apply them of change their direction. – Remove the PVC tape from the ends of the pipe to perform flaring. 2 1 Fig. 44 – Tighten the end of the pipe (1) in the template (3) of the flaring tool. The end of the pipe must extend beyond the edge of the template, according to the measurements indicated in the underlying table. – Apply the flaring screw on the template. – Turn the screw clockwise until the right flare is obtained. PIPE PROJECTION BEYOND THE TEMPLATE Outer diameter of the pipe [mm] Min. A [mm] Max. Ø 9,52 (Ø 3/8”) 1,0 1,6 Ø 15,9 (Ø 5/8”) 2,0 2,2 3 1 A Fig. 45 – Remove the flaring screw and the template then check that the pipe end has been uniformly flared and is free of cracks. 1 2 3 4 5 6 7 8 1 Correct 2 Oblique 3 Damages to the sealing surface 4 Cracks 5 Different thickness 6 Insufficient flanging 7 Excessive flanging 8 Incorrect flanging angle 4.1.4 Piping connections Fig. 46 First connect the low-pressure pipe and then the high-pressure pipe. a When bending the connecting pipes of the cooling system, observe a minimum radius adequate to the pipe diameter. To make the connection, proceed as follows: – Align the centre of the two pipes to be connected. 1 Threaded pipe 2 Flared nut 3 Flared pipe 1 2 3 – Screw on the flared nut by hand as far as possible. – Then insert a spanner on the nut. Fig. 47 – While keeping the nut firmly fastened to the unit’s pipe, use a torque wrench to tighten the flared nut according to the torque values shown below. TIGHTENING TORQUE VALUES Outer diameter of the pipe [mm] Tightening torque [Nm] Liquid side Ø 9,52 (Ø 3/8”) 20 - 25 Gas side Ø 15,9 (Ø 5/8”) 40 - 55 28 / EN

Hydraulic and refrigerant connections a – Slightly loosen the flared nut then tighten it again. An insufficient torque can cause gas leakages. Use the values indicated in the table. OUTDOOR UNIT C B C A 4.1.5 Preserving the pipes a a a a Check that the pipes do not contain moisture, processing residues and dust After making the collars, clean the pipes with compressed air to remove any processing residues. Make sure that the pipes are adequately insulated. Make sure that the pipes are not crushed. If the pipes are not mounted together with the unit, seal the ends of the pipes with caps or press the ends and braze the open parts. 4.2 Checking tightness INDOOR UNIT A Fig. 48 Once the pipes have been connected, the circuit of pipes leading to the indoor unit must be checked for pressure tightness. i a Make sure that all the shut-off valves of the outdoor unit are closed with an adequate torque and that the valve caps are mounted and suitably tightened. This procedure involves the use of pressurised nitrogen. Be very careful. The tightness inspection procedure must be carried out in two phases: – Pressurised resistance test with nitrogen – Pressurised tightness test with nitrogen Fig. 49 VALVE TIGHTENING TORQUE VALUES Make sure that the points shown in "Fig. 48" and "Fig. 49" are tightened properly to the following torque values: 2 Reference Tightening torque [Nm] Ø 3/8" Ø 5/8" A Flared nut 20 - 25 40 - 55 B Cap 10 10 C Cap 20 - 25 30 - 35 1 3 1 Gas-side flare valve 2 Pressure reducer and pressure gauge 3 Nitrogen cylinder Fig. 50 29 / EN