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Solutions for thermostatic mixing valves /


               4. SIZING THE APPROPRIATE PREMIX
                                                                                                      Chart of PRESSURE
                                                                                                      LOSSES:
               The choice depends on the design corrected flow rate and pressure loss.                 Dynamic pressure drop
                                                                                                      when operated under
               1. Select the PREMIX size depending on design corrected flow rate for mixed water in the system.  varying flow rates.
               2. Check the PREMIX pressure loss.                                                     REMINDER: Check
                 Having established the dynamic pressure at the thermostatic mixing valve inlet and the required residual   pipework pressure
                 pressure for supplying installation, select the model chosen based on the associated pressure drop.   losses (e.g. different
                                                                                                      floor levels, extended
               Example:                                                                               supply pipes, etc.).
               For a 50 lpm design flow rate:                                                          See chapter "Sanitary
               The PREMIX ¾" records a 2.4 bar pressure loss as opposed to 0.9 bar for the PREMIX 1".  technical data"
                                                                                                      (page 258).
               NB: When supply pressure is 3 bar (recommended), pressure loss should not exceed 1 bar.
                                                                                                      Due to the diversity
                                                                                                      of fittings possible,
                                                                                                      this information is
                                                                                                      not contractual and
                                                    PREMIX          ¾"       1"     1¼"    1½"        is for guidance only.
                   3                                                                                  The designer remains
                                                                                                      responsible for
                                                                                                      determining the best
                   2
                                                                                                      simultaneity coefficient
                   1.5                                                                                and TMV model.
                   1                                                                                                         THERMOSTATIC   MIXING VALVES
                 Pressure drops  P in bar  0.6
                   0.9
                   0.8
                   0.7
                   0.5
                   0.4
                   0.3


                   0.2




                   0.1
                       3   4  5  6  7 8 910       20     30   40  50 60 70 80 100      150  200
                                                    Flow rate in lpm



































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