PICVs in HVAC systems combined with variable speed pumps provide even higher energy efficiency. When sizing the pump, it must be made certain that the most critical branch or consumer in the system – usually the most remote from the pump – receives enough pressure (pump head). Thus, it is recommended to use a variable speed pump in constant-pressure mode with end-point feedback, to maintain a minimum differential pressure across the critical valve.

 

Residential buildings

Residential buildings with, for example, self-contained flat heating systems:

E

=

Floor

G

=

Group or zone

Non-Residential buildings

Commercial buildings with, for example, fan coil units or heat exchangers for heating or cooling: