8 Types of Evaporative Coolers You'll Want to Know About
Evaporative cooling is the type of cooling method that you should choose if you'd like to experience a constant breeze across your skin.
It's one of the most efficient home-cooling options out there, and can save homeowners a lot of time and money throughout the way.
The parts of an evaporative cooler aren't exceptionally complicated to understand, and don't require a lot of general maintenance.
Plus, you'll be able to save thousands of dollars during installation compared to a regular air conditioning unit.
But with so many different types of evaporative coolers (like the direct evaporative cooler or the indirect evaporative cooler as examples), which ones should you choose? In the following sections, we'll talk about the different types of evaporative coolers, their functions, benefits, and how their performances match up against one another.
Overview of the Different Types of Evaporative Coolers
There are many different types of evaporative coolers to choose from, which can make it challenging to find the right one for you and your home. Some of the more common ones that you'll see, and that we'll talk about in this article, include:
- Direct Evaporative Coolers: These models will cool down surrounding air and then release it into the medium, helping increase humidity and remove stagnant air from the vicinity.
- Indirect Evaporative Coolers: Being a little different than direct systems, they will use an evaporative media that will be suited inside of a cooling tower. This will help cool water down to the temperature that is approaching the web bulb temperature.
- Up-Draft Units: These units are usually installed on the floor of your home, and will blow cool air in an upwards direction into your home.
- Down-Draft Units: A down-draft unit will be installed on a roof, and will blow cool air in a downward direction into your home. These are the most popular options for most homeowners, but it's important to note that they can be the most expensive and time-consuming to maintain.
- Side-Draft Units: A side-draft unit will be installed on the side of a home, usually in a window, and will blow cool air into the home in the same fashion as a window-mounted air conditioner might.
- Standalone Systems: Standalone systems require a designed ductwork.
- Combined Systems: These units require the share of a ductwork.
- Portable Evaporative Coolers: Are better-designed for smaller living areas, even individual rooms.
Judging from this list, it's easy to see just how many different types of evaporative coolers there are.
Each offer their own unique set of advantages and disadvantages, and will require different maintenance procedures and installation costs.
What is Direct Evaporative Cooling?
With a direct evaporative cooler, the outside air is going to be blown through a medium that is water-saturated, which will then be cooled down via evaporation.
- The cool air that's accumulated will be circulated with the help of a blower.
- Direct evaporative cooling units help moisten the air until the humidity in the vicinity has risen to a significant level.
- It's important to note that that web bulb temperature will remain the same while the dry bulb temperature will be reduced.
Indirect Evaporative Cooling
When looking at the different types of evaporative coolers, an indirect evaporative cooler is another option to keep in mind.
- With these units, you will find a secondary air stream, known as a "Scavenger" that is cooled by water. The air that's cooled through the secondary air stream will then go through a heat exchanger.
- Here, it will help cool the primary air stream.
- The cooled primary air stream is what will later by circulated by the blower and released into the surrounding area.
- Indirect evaporative coolers do not add moisture to the primary air stream.
Both the web bulb temperatures and dry bulb temperatures will be reduced, and during a heating season, the indirect system's heat exchanger has the ability to preheat air on the outside of the system if the exhaust air is being used in the secondary air stream.
Different Types of Mounted Evaporative Cooling Systems Explained
Whenever an evaporative cooler is being installed on the outside of your, there are several locations that you can choose to have it placed. These include:
- Roof (Down-Draft Units)
- Window (Side-Draft Units)
- Ground (Up-Draft Units)
Roof mounted units tend to be the most common, but they can also be the most difficult to maintain. One of the reasons why homeowners prefer down-draft units is because they are often the easiest to install and connect with a duct system that already exists in your home.
As their name implies, side-draft units will be installed on the side of your home (typically a window), and will release cold air into the medium just as a window air conditioner might.
Ground, or up-draft units, aren't as common as the two discussed above, but they are still an option for homeowners.
Distinguishing Evaporative Cooler Models Based on the Requirement of a Duct System (or Lack of a Need)
It's important to note that a mounted cooler will usually be connected to a duct that will help bring in the cooled air into the various parts of your home or building.
In certain cases, an existing ductwork can be used to help move air throughout the different rooms. In fact, roof mounted systems are the easiest to connect to these ducts since they are already situated in the ideal places in a home to make it happen.
Alternatively, you can install a new ductwork so that it is specifically designed for an evaporative cooler to bring air into the rooms of a home.
This will depend directly on the type of system that you're going to be installing. The three main ones include:
- Standalone Evaporative Coolers (Require a designed ductwork)
- Standalone Alternative to a Refrigeration System (Require a designed ductwork)
- Combined System (Require the sharing of a duct work with an existing refrigeration system)
One of the problems that homeowners are going to find associated with the combination system is that the refrigeration ducts will be too small to help move the air that is required by an evaporative cooler (it will cause more noise and lessened overall airflow). Also, a combined system might require that you install a damper that is separate to the actual unit.
Otherwise, the air that is being refrigerated will escape through the evaporative cooler, and the moist air will slowly erode the refrigeration system.
In smaller opens that have a lot of open space, cooled air can easily be blown into a central location without having to install a ductwork, which will save a lot of time and money.
When Should You Purchase a Portable Evaporative Cooler?
Portable evaporative coolers are better designed for smaller living areas. In fact, they are perfect for cooling only single rooms, and usually won't do a very good job at cooling an entire home (especially if it's quite large).
For this reason, portable evaporative coolers are typically much cheaper than ones that need to be installed on the roof along with a ductwork system. Units like these can cost as little as a few hundred dollars, with the more expensive ones hovering around a $1,000 or more.
- Some portable evaporative coolers come with wheels that you can use to roll around from room to room within your home.
- Similar to a portable fan, a portable evaporative cooler can be transferred quite easily.
- But the main reason why it is recommended over a standalone fan is because evaporative coolers help decrease the amount of stagnancy in the air, and will promote moisture that can help increase respiratory health, especially if you are someone who lives in a dryer environment.
Learn more about what you need to know before buying an evaporative cooler here.
How Much Does it Cost to Install a Regular Evaporative Cooler?
Installing a regular evaporative cooler, one that will sit either on the roof or in a window, will cost more than a portable unit. More specifically, the cost of a regular unit will hover between $2,000 and $3,500.
While this might sound like a lot of money to some homeowners, it's important to note that this is far less than the amount that one might spend on an air conditioner.
Plus, maintenance costs for evaporative coolers are very, very small, but do vary depending on the size of your home and the frequency by which it is being used.
Conclusion
After determining the size of your home, your personal needs, and the geographic location, you can go ahead and make a decision as to which type of evaporative cooler is right for you.
In general, portable evaporative coolers are better designed for single rooms while window or roof-installed models are better designed for larger homes that contain several rooms.