Stuart Turner Monsoon U1.5 bar Twin Installation, Operation & Maintenance Instructions Manual page 17

8.3 Hose to Pipework
The hoses are fitted with plastic push-in connectors, which must only be
connected to the following:
22 mm dia. pipework in the UK.
21 mm dia pipework in the ROI.
1. Ensure the pipe is free from all score marks and deformities in the area of
the insertion depth (Figure 8) and cut the pipe square, removing all burrs
and sharp edges to prevent damage to the sealing 'O'-ring.
2. Prior to inserting pipe into fitting mark the insertion depth on the wall of
the pipe with a soft pencil at a distance of 33 mm from the end to be
inserted.
Pencil mark
Figure 8
22mm pipe
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