设备和系统
Air-Cooled vs. Water-Cooled Chillers: Selection Criteria
Compare air-cooled vs. water-cooled chillers. Understand selection criteria to make the best choice for your cooling needs.
Refrigeration Expansion Valve Sizing and Selection Process
The proper selection and sizing of refrigeration expansion valves is a systematic process requiring careful consideration of multiple parameters. Selecting the right expansion valve involves understanding system requirements, calculating correct capacities, and accounting for operating conditions such as subcooling and pressure drop.
Refrigeration Condenser Sizing and Selection
The proper sizing and selection of refrigeration condensers is a complex process that requires careful consideration of multiple factors, including heat load calculations, environmental conditions, system requirements, and efficiency goals. By following a structured approach that considers all relevant parameters, engineers can select condensers that provide optimal performance while minimizing energy consumption and maintenance requirements.
Constant Volume Air Handling
Constant Volume Air Handling design principles and control strategies, with particular emphasis on energy optimization and frost protection mechanisms.
Cooling Load Rules Of Thumb
Cooling Load Rules Of Thumb for HVAC design of Banks, Court Houses, Municipal Buildings, Town Halls, Police Stations, Fire Stations, Post Offices, Precision Manufacturing, Computer Rooms, Restaurants, Kitchens (Depends Primarily on Kitchen Equipment), Cocktail Lounges, Bars, Taverns, Clubhouses, Nightclubs, Hospital Patient Rooms, Nursing Home Patient Rooms Buildings w/100 percent OA Systems (e.g., Laboratories, Hospitals) Medical/Dental Centers, Clinics, and Offices Residential Apartments (Eff., One-Room, Two-Room) Motel and Hotel Public Spaces Motel and Hotel Guest Rooms, Dormitories School Classrooms Dining Halls, Lunch Rooms, Cafeterias, Luncheonettes Libraries, Museums Retail, Department Stores Drug, Shoe, Dress, Jewelry, Beauty, Barber, and Other Shops Supermarkets Malls, Shopping Centers Jails Auditoriums, Theaters Churches Bowling Alleys
Induction (Air/Water) System
Perimeter induction units – usually located under windows – blend primary air from the air-processing unit with secondary air from within the room. The high-velocity processed air delivery is induced into the unit through restrictive nozzles.
Indoor Design Conditions
Indoor design conditions for HVAC design of Office Buildings, Commercial Facilities General Spaces, Educational Facilities, Food and Beverage Service, Hotels, Motels, Resorts, and Dormitories, Correctional Facilities, Retail Stores and Specialty Shops Theaters, Sports and Entertainment, Transportation, Storage Facilities, Workrooms, Private Dwelling—Single and Multiple, Laboratories, Computer Facilities, High-Tech Industrial, Special Facilities, Hospital Nursing Units Obstetrical Facilities, Emergency, Surgery, and Critical Care, Hospital Facility Support Areas, Diagnostic and Treatment Areas, Hospital Service Areas Sterilizing and Supply…
Fancoil (Air/Water) Unit And Induction Diffuser
An alternative discharge unit for application to the induction system shown on the previous page. Instead of nozzle injection of air, a low-powered fan is used to disperse a mixture of primary and secondary air after reheating or cooling from an energy exchanger within the unit.
Dual Duct System
The dual duct system is another means of providing varying air temperatures to different rooms in the same building. There is no water circulation to peripheral discharge units with terminal reheaters or coolers. This simplifies the plumbing installation as heating and cooling elements for each duct are located in the plant room. However, the system is space consuming and adequate provision must be made in suspended ceilings or raised flooring to accommodate both distribution ducts. The system is most energy economic when heating and cooling elements operate individually.
Variable Air Volume (VAV)
The VAV system has a central air-processing unit to produce air at a specified temperature and relative humidity. The conditioned air from the main unit is conveyed in ductwork to ceiling diffusers which incorporate thermostatically controlled actuators. These can change the air volume to suit each room load. In a large room, several of these VAV ceiling units may be controlled by one room thermostat.
控件和自动化
HVAC Control Diagrams
In this blog post, we will introduce some of the most common HVAC control diagrams. We will also provide a brief explanation of each diagram and how its components work together. HVAC control diagrams are essential tools for designing, installing, and maintaining HVAC systems. They provide a visual representation of the system’s components, how they are interconnected, and how they are controlled. This information can be used to troubleshoot problems, optimize performance, and make informed decisions about system upgrades.