Wednesday, August 16, 2017

Know Your Drying Equipment

As a water restoration professional it is important to constantly educate yourself on how to use new technology and equipment that is coming on the market. It would be ridiculous to think that you had to do your job today with technology that is 30 or 40 years old. However many water restoration companies are doing just that with old dehumidifier technologies and old air mover technologies. So let’s look at a few examples of older technologies that are just getting repackaged in a fancy housing and sold today.

Air movers

First centrifugal air movers have been around for a long time. Decades ago we thought one or two airmovers on a job was fine and so amp draw on them was not much of a concern. However it did not take long for that to change. Some of the first models would pull about 11 amps of electricity. Thankfully I don’t see many of those anymore but there still are some of them around. However I do see plenty of airmovers that still pull 7-8 amps. Compare that to some made today with newer motor technology that pull around 2 amps. This means instead of being able to only get one air mover on a 15 amp breaker then you should be able to get 5-6 on that same breaker. Also with the addition of axial air movers which come in between 1.5 and 3 amps and the even newer low profile air movers then there are plenty of options to blow a lot of air while using the electricity available to you more efficiently than in the past. Some of the new low profile air movers have selectable amp draw which is nice to be able to see exactly what kind of electricity you are pulling.


Even with the invention of low grain dehumidifiers there are still plenty of companies that are using conventional dehumidifiers to attempt to dry a home or office. Conventional dehumidifiers can also be known as professional, heavy duty, or standard dehumidifiers. These dehumidifiers are inexpensive to buy and they are still massed produced today. Here’s the main difference in how the two function. A conventional dehumidifier will only have one set of coils and will only pass the air over the coil one time before leaving the machine. A low grain refrigerant dehumidifier will either have two coils or pass the air over the one coil twice before exiting the machine. What this does is allow the dehumidifier to get the air closer to the dew point on the first pass and then dump a considerable more amount of water on the second pass. This produces air that is drier than conventional refrigerant dehumidifiers. Low Grain Refrigerant dehumidifiers can get the grains of moisture per pound (gpp) of air down to 30-32. A conventional dehumidifier will only get the gpp down to 55-60. So if you are trying to dry carpet, pad, sheetrock, cabinets, wood floor, paneling, wooden beams, etc. within a home then using a low grain refrigerant dehumidifier is the way to go. In my opinion conventional dehumidifiers have no place in the water restoration industry.

Comparison of LGR units

Dehumidifier A – 70 pints of water removal per day at AHAM (80° - 60%) 5.6 amps, 160 cfm

Dehumidifier B – 135 pints of water removal per day at AHAM (80° - 60%) 7.2 amps 380 cfm

Dehumidifier C – 130 pints of water removal per day at AHAM (80° - 60%) 8.0 amps 400 cfm

Dehumidifier D – 170 pints of water removal per day at AHAM (80° - 60%) 11.2 amps 400 cfm

Dehumidifier E – 161 pints of water removal per day at AHAM (80° - 60%) 8.9 amps 380 cfm


To me Dehumidifier A and D would not be one of my first choices in buying a dehumidifier. Here’s why. If I was using dehumidifier A it would take two of them to equal the water removal of dehumidifier B or C. I would then be using 11.2 amps with two units and still not have the cfm of either B or C. Dehumidifier D would not be one of my choices because of the amp draw. An additional 9 pints of water per day and 20 cfm over dehumidifier E is not worth the additional 2.3 amps it would take to use this dehumidifier. I could use Dehumidifier E at 8.9 amps and put in another axial air mover (3000 cfm) at 2.5 amps and roughly be at the same amp draw as dehumidifier D by itself. For me B,C, and E would be excellent choices for the water restoration professional who wants to maximize their water removal per amp of electricity used. There are also other factors to consider when buying a dehumidifier such as what range of temperature does it function best in. Most refrigerant dehumidifiers work best between 70° - 90°. However there are some dehumidifiers on the market that will also operate efficiently above 90° and still have the high water removal with the low amp draw. These are the units I would choose because they give you the most options when drying a home or office.

The point is that if you need to know how the equipment operates before you purchase it. Look for air movers that move a lot of air with very little amp draw. With refrigerant dehumidifiers look for low grain dehumidifiers that pull the most water for the least amount of amp draw. Don’t buy things just because it has a fancy control panel, a plastic housing, or is a certain color. Know how the equipment will perform. Buying equipment that performs well may cost more up front but you will be able to dry more things within a structure without tearing it up which should result in more business for you down the road from referrals of satisfied customers.

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