Setup of makeup water pumps for closed water systems

With the provisions in relating codes, states that normal makeup water pumps and accident makeup water pumps should be set separately for a closed HVAC water system. Normal makeup water pumps provide makeup water in normal operation with the water flow rate of one percent of system water volume or of two percent of circulating water quantity of a heating system, applying variable frequency control at the same time. There should not be too many accident makeup water pumps in a system, but the number of the pump should not be less than two. It is unnecessary to install spare pumps for normal and accident makeup water pumps.