Humidity Basics: Part 2 – Dehumidifying

We all know about space temperature but when it comes humidity not many have a grasp of the subject. This engineering white paper (EWP-7.b) is a supplement to the humidity basics engineering white paper EWP7. While the previous white paper focused on preventing dry conditions by maintaining relative humidity generally ≥40%rh, this white paper focuses on preventing humid conditions. We used dehumidification equipment (removal of moisture from the air) to maintain relative humidity generally ≤60%rh. But before we dive into dehumidifying let’s do a quick review on humidity in general.

Effects of Altitude on Psychrometric Calculations & Fan Selections

When designing airside systems a change in elevation can significantly alter the results for Psychrometric calculations and Fan selections. For this reason it is important that you understand what causes these changes. In knowing what causes the changes to these values you will be better prepared to support your design engineer on projects at elevation.

Heat Exchangers

The HVAC industry is inundated with heat transfer equipment or heat exchangers. This white paper is designed to make you aware of the most common you will find in our industry. This is not a compressive list but more of a primer to get you thinking big picture.

Future Refrigerants

Refrigerants in the HVAC industry are changing. Historically, the focus has been to reduce Ozone Depletion Potential (ODP) by eliminating refrigerants that have Chlorine. In the last 10 years, the focus has shifted to lowering Global Warming Potential (GWP).

Water Coil Basics

Selection software programs abound and each one of our coil manufacturers has their own program to facilitate easy selection & pricing. But what is missing in the software is the logic behind the how & why we select a particular coil for an application. With a dozen variables which make up a coil’s physical construction there are countless solutions available when designing a coil.

Air to Water Heat Pumps

Air to Water Heat Pumps have become a dominant technology used to provide building heating and cooling. Since AWHP’s utilize the refrigerant cycle, they can provide building heating with a COP between 2.0 – 4.0. For comparison, Electric heat has a COP of 1 and gas heat has a COP of 0.8 – 1.1 (standard vs. condensing furnace).

Mechanical Refrigeration Cycle

Before we can advocate for our customers on HVAC compressorized equipment we must know the basics of the mechanical refrigeration cycle. Mechanical refrigeration is the process of using a volatile fluid (refrigerant) to absorb heat from a lower temperature place, raising the fluid’s pressure and temperature so it can be rejected to a higher temperature place.

Thermodynamics

Before we can advocate for our customers on HVAC equipment & system design we must know the basics of Mechanical Engineering. Key to the understanding of this disclipline is Thermodynamics & Heat Transfer. This EWP is dedicated to Thermodynamics.

Return Fans Verses Exhaust Fans

It is easy to understand what each type of fan does by virtue of it is name but knowing when to apply an exhaust fan vs a return fan is not so obvious. This white paper explains when & how to apply these fans.

Cooling Tower Water Treatment

Evaporative cooling is the most energy efficient cooling method, but it also requires a high degree of maintenance in addition to water consumption. The most common problem with evaporative equipment is poor water treatment. By offering effective and easy water treatment much of that maintenance downside of evaporative cooling can be minimized. Water treatment must manage three problems: scale, corrosion, and biological growth. This paper will discuss the causes of these problems and two solutions: chemical water treatment or chemical-free treatment systems.