Whenever you hear of a building where occupants are constantly complaining about poor temperature regulation, it’s a pretty safe bet that the HVAC system is not properly balanced.
There are two sides to HVAC system balancing the air side and the water side. The output of any terminal unit, be it a baseboard radiator, coil or water-source heat pump, is directly related to the change in temperature of the air and the fluid flowing through it. The change in temperature of these mediums, among other things, is a result of their respective flowrate. So there we have it, for an HVAC system to perform properly, the flowrates have to be right.
Balancing is the method used to compensate for variations in the pressure losses so as to ensure designed flow rate through each load.
Besides adjusting a building’s air and water system to design conditions, TAB well identifies three major types of problems:
Conditioned air is the only heat carrier at room side. If it is not balanced properly, you won’t feel comfort; though you have invested a good amount of money to install a highly efficient HVAC system.
When the indoor air is not balanced, the air conditioner needs to work harder to maintain designed temperature and that may prove to be costly.
All you want is your AC system should cater the comfort at room side and air is the only media to carry away heat from your room. It’s a very basic common sense, if the room is not getting sufficient conditioned air to replace the heat load; you won’t get the desired temperature inside the room though designer has designed and installed the system with good engineering.
Any condenser or evaporator coil always designed with a specific water flow and water is the only media which carries away the load from coil. If the coil is not getting sufficient or designed water flow; it will become inefficient to displace the load from conditioned space and eventually you won’t get desired comfort.
Though the water system is designed without any flaws and still coil is having deficiency of chilled or hot water flow, there will be only one reason behind this i.e. improper distribution of water. To get the efficient working of water distribution system; balancing is equally important like its design.
Theoretically it is possible to design plants that deliver the design flow at each terminal unit (heating or cooling device).In reality this is not possible because pipes and valves only come in certain sizes and accurately predicting the real flow in a system is too complex, which may cause underflow.
Hydronic Balancing is the process of optimizing the distribution of water in a building’s heating or cooling system so it provides the intended indoor climate at optimum energy efficiency and minimal operating cost.