Prompt Consulting

  What do you mean by Static Pressure? Static pressure describes the resistance experienced by air as it travels through an  HVAC system . In other words, it is the pressure a fan must overcome to move air through ducts, as needed for heating, ventilation and cooling. Static pressure and airflow are the two main aspects that determine the operating point of a fan, as well as power consumption. Various types of HVAC equipment establish an airflow through ducts, and two common examples are air-handling units (AHU) and packaged rooftop units (RTU). These pieces of equipment are designed to deliver a specific performance in terms of airflow and velocity. For an HVAC system to operate normally, equipment capabilities must match the needs of the air duct system. In particular, air handling systems must be capable of overcoming the static pressure. Other parameters considered by HVAC designers include the installed cost, operating expenses, maintenance, noise and vibration. Air Duct D

The Integrated Part Load Value (IPLV) is a performance characteristic developed by the Air-Conditioning, Heating and Refrigeration Institute (AHRI). It is most commonly used to describe the performance of a chiller capable of capacity modulation.  Unlike an EER (Energy Efficiency Ratio) or COP (coefficient of performance), which describes the efficiency at full load conditions, the IPLV is derived from the equipment efficiency while operating at various capacities. Since a chiller does not always run at 100% capacity, the EER or COP is not an ideal representation of the typical equipment performance. The IPLV is a very important value to consider since it can affect energy usage and operating costs throughout the lifetime of the equipment. Energy codes such as ASHRAE Standard 90.1 specifies minimum values for the equipment. Fig 1: Water Cooled Chiller The IPLV is calculated using the efficiency of the equipment while operating at capacities of 100%, 75%, 50%, and 25%. For the purpose