Data, Tables, Tools, Guides
It is likely, but not yet shown, that COVID19 could be spread through the air.
Air cleaning can help mitigate disease transmission.
Options for air cleaning include:
HVAC systems
In-Room devices
Technologies that can be effective include:
Mechanical Air Filters
Electronic Air Filters/Air Cleaners
UV-C Systems
Other Emerging Technologies
A brief history of HVAC (Heating, ventilation, and air conditioning)
The thermodynamic processes in the refrigeration cycle are complex. Calculation using formulae and tables requires a considerable amount of effort due to the three different states of the refrigerant from liquid, boiling and gaseous. Therefore, for reasons of simplify cation, the log p-h diagram was introduced.
The idea of using a refrigerant diagram is that it makes it possible to represent the processes in the refrigeration system in such a way that analysis and evaluation of the process becomes easy.
Closed-loop systems can be further classified as direct return or reverse return. The direct return system allows piping to be run in the most direct path to optimize piping costs. The reverse return system is piped so that the length of the water circuit through the supply and return piping to each fan coil or air handler is essentially the same.
There are four main types of water distribution systems. They are defined by the number of pipes used in the system – 1-pipe, 2-pipe, 3-pipe, and 4-pipe. While this article will discuss primarily chilled water and condenser water system piping system design, it is important to understand the evolution from 1-pipe into the other three systems, all of which are used for heating as well as cooling.
Understanding of the three basic types of piping systems: closed-loop, open-loop, and once-thru. Closed-Loop (Evaporator), Open-Loop (Condenser), Once-Thru.
Gauge (or gage) sizes are numbers that indicate the thickness of a piece of sheet metal, with a higher number referring to a thinner sheet. The Calculator below can be used to determine the equivalent sheet thickness, in inches or millimeters, for a gauge number from the selected gauge size standard.
A heat rejection system can take several forms. The most efficient is the evaporative cooling tower which uses the cooling effect of evaporating water to boost the cooling provided by fresh air.
Heating Load Factors for HVAC desgn. Safety Factors, Heating Load Credits, Heating System Selection Guidelines and ASHRAE Standard 90.1.
Diversity factors are an engineer’s judgement applied to various people, lighting, equipment, and total loads to consider actual usage.
Fuel Conversion Factors for Electric Baseboard to Hydronic Baseboard, Electric Furnace to Hydronic Baseboard, Ceiling Cable to Hydronic Baseboard, Heat Pump to Hydronic Baseboard, Electric Baseboard to Warm Air Furnace, Electric Furnace to Fuel-Fired Furnace, Ceiling Cable to Warm Air Furnace, Heat Pump to Warm Air Furnace, Warm Air Systems to Hydronic Baseboard System.
Variable-geometry supply diffusers can be used to ensure adequate air movement when the supply volume is low.
This duct calculator allows three different calculations to be carried out quickly and with ease. These calculations are divided in four areas
Variable air volume (commonly known as VAV) cooling is an all-air system which can satisfy the individual cooling requirements of multiple zones, typically within office buildings. This is achieved by supplying air at a constant temperature from a central plant to one or more VAV terminal units in each zone.
Constant volume cooling is a simple system often used to provide tempered fresh air in multi-zone buildings containing partially centralised air/water systems (such as a fan coil installation).
Air-duct calculators are very useful tools to use when sizing duct
These clinics are comprehensive and detailed courses used to educate on the fundamentals heating, ventilating, and air conditioning (HVAC). Each clinic includes a student workbook, with corresponding quiz questions/problems.
The most common types of cooling system can been classified as centralized or partially centralized air/water systems, or local systems.
Technical Development Programs (TDP) are modules of technical training on HVAC theory, system design, equipment selection and application topics. They are targeted at engineers and designers who wish to develop their knowledge in this field to effectively design, specify, sell or apply HVAC equipment in commercial applications.
Download all 11 chapters of Carrier System Design Manual.
This guideline is intended for the guidance of the industry, including manufacturers, engineers, installers, contractors and users.
Refrig quickly calculates the maximum refrigeration load in btu’s per 24 hour period for all types of refrigeration applications. Refrig has provision for all kinds of loads including: roofs, walls, partitions, floors, products, containers, infiltration, lights, equipment, people, defrost, compressor run-time, and more.
Rhvac can calculate peak heating and cooling loads (both block and room by room) for residential buildings and some light commercial applications in accordance with ACCA Manual J, D, and S. Rhvac include a complete ACCA Manual D duct sizing capability and a complete Manual S equipment selection.
NAIMA’s FREE 3E Plus® software program makes it easy to calculate the appropriate insulation thickness necessary for any application. To ensure accuracy, the program has customizable inputs for every aspect of your job—and offers default values if your exact numbers aren’t available.
CHVAC is a software program designed to help HVAC professionals design, analyze, and troubleshoot HVAC systems. It is used by engineers, contractors, and technicians to design, analyze, and troubleshoot HVAC systems. The software includes a library of components, such as air handlers, chillers, boilers, and pumps, as well as a library of materials, such as insulation, ducts, and piping. It also includes a library of tools, such as psychrometric charts, psychrometric calculators, and energy calculators. The software also includes a library of reports, such as energy audits, load calculations, and system performance reports. CHVAC is a powerful and comprehensive tool for HVAC professionals.
The pressure-enthalpy diagram (log P/h diagram) is a very useful tool for refrigerant technicians, engineers and researchers. Since it’s not always possible to have all of these diagrams together, we decided to give you this complete pack.
Below you can see ASHRAE chart of HVAC Equipment Life Expectancy. The chart includes a list of median life expectancy for the following types of equipment:
ASHRAE 52.2: Filter testing was originated from America in 1930 (ASHVE and AFI code). It was then reviewed and modified in 1967 and 1968. ASRHAE collaborated with American National Standard Institude (ANSI) in 1992 to create ASHRAE-ANSI 52.1. Finally updated to ASHRAE 52.2 in 2007.