Where should I install the balancing valve: in the supply or in the return?
The manual balancing valves (STAD, STAF, TBV) are traditionally installed in the return pipe where the temperature and pressure demands are lighter then in the supply[MaH1] . Nevertheless it is impossible sometimes to keep the necessary length of straight pipe before and after the valve. Since the balancing valve changes the resistance of the hydronic circuit wherever it is installed in the circuit it is allowed to install it in the supply unless there is not any other contra-indication (e.g. too high temperature). The key aspect is to keep the compulsory distances. So the manual balancing valves can be installed in the return, in the supply and sometimes if the control loop requires in the by-pass. The standard differential pressure controllers (STAP, DA) have to be installed in the return pipe because they transmit the lower pressure signal to the membrane in the valve body. The right flow direction is marked with an arrow on the valve.
