Frequently Asked Questions

See below for answers to some of our more freqently asked questions.  If your question is not listed, please Contact Us and one of our representatives will get back to you shortly.

91 Result(s)
Can rooftop air conditioners and portable dehumidifiers be used to control the climate in an indoor grow room facility?

Rooftop air conditioners can be installed and sized to handle the cooling load of the room(s) and will remove a small portion of the necessary room moisture during the lights-on growing phase. The portable dehumidifiers will try to make up for the rooftop units’ dehumidification shortcomings.

The dehumidifiers have a very large job to fill that often gets missed as humidity levels are critical. During the lights-off phase of the room, portable dehumidifier(s) are the primary equipment used to remove moisture. 

 

Here’s the problem, when the portable dehumidifiers are in operation, the air temperature leaving those units is 25°F warmer than the air getting sucked in. This causes the rooftop air conditioners to turn on and try to remove that excess room heat and then quickly turn off again when their task has been completed. They are two competing forces.

 

The frequent on/off of an air conditioner causes the expensive compressors within those units to die much sooner. From the grower’s perspective, this system causes massive temperature and humidity swings within your grow room space. Your plants will be susceptible to browning, mold, and a much smaller post-harvest yield than a finely controlled space. This is a huge headache for someone trying to grow profitable medical-grade Cannabis.

 

Pros and cons of traditional "rooftop" HVAC units with portable dehumidifiers in a grow facility

Pros

  • Cheapest option
  • Easy to install
  • Simple service

Cons

  • No precise temperature/humidity control (units are constantly fighting each other)
  • Very high utility bills
  • Comfort cooling solution for people, not plants
  • Odor control and biological-contamination challenges
  • No trending or ability to link everything together for a precise understanding of the space conditions
  • Often expensive reheat option is still needed to not over cool the rooms
  • Changing the temperature on the rooftop unit will mean the dehumidifiers won’t operate the same and you’ll have to adjust each one independently.

For more information read the blog, “The Ultimate Indoor Grow Room Climate Control Showdown

Can VRF units with portable dehumidifiers control the climate in a grow space?

VRF systems are very similar to the traditional rooftop air conditioning units with even more challenges for an indoor grow climate environment.

VRF is a comfort cooling engineered solution. They are designed for offices, hotels, etc. and are installed and sized to handle the cooling load only. Like rooftops, they will remove a small portion of the necessary room moisture during the lights-on grow mode.

There will be a high number of VRF cassettes (The ceiling boxes with vents and fans) in the space delivering cold air to help offset the temperature load of the lights.

 

Dehumidifiers help with the work of the air conditioner in the lights-on mode. The portable dehumidifiers have a very large job that often gets missed as humidity levels are critical.

 

In lights-off mode, portable dehumidifier(s) are still used to remove the moisture.  The problem is the same as challenger 1 when the portable dehumidifiers are in operation, the air temperature leaving those units are 25°F warmer than the air entering. This causes the VRF air conditioners to turn on and try to remove that excess heat and then quickly turn off again when their task has been completed.

 

Frequent on/off of a VRF outdoor unit causes the expensive compressors within those units to break much sooner. The grower ends up with the same problems, this system causes massive temperature and humidity swings within your grow room space. Your plants will be susceptible to browning, mold, and a much smaller post-harvest yield than a finely controlled space. This is a huge headache for someone trying to grow profitable medical-grade Cannabis.

Pros and cons of VRF units with portable dehumidifiers in the grow space:

Pros

  • Marginally lower utility bills than rooftop units
  • “Off the shelf” equipment

Cons

  • No precise temperature/humidity control (units constantly fighting each other)
  • Very high utility bills compared to our premium options
  • Comfort cooling solution for people, not plants
  • Odor control and biological-contamination challenges
  • Lots of units delivering cold air onto the plants will cause condensation to form on the leaf, which can lead to mold
  • VERY HIGH levels of refrigerant being pumped around the space, which is extremely unhealthy if there is a leak
  • Lots of compressors and fans between the VRF systems and the portable dehumidifiers. This means there are even more failure points and expensive repairs to consider.
  • No trending data or ability to link everything together for a precise understanding of the space conditions
  • Changing the temperature in the VRF system will mean the dehumidifiers won’t operate the same and you’ll have to go adjust each one.

For more information read the blog, “The Ultimate Indoor Grow Room Climate Control Showdown

Do dehumidifiers give off heat?

Yes without a remote condenser setup all dehumidifiers eject heat back into the space. The more dehumidifiers dehumidify the more heat they generate. Desert Aire integrated HVACD systems offer dehumidification without temp rise for more stable control. 

How do I install a CM3500 controller?
How do I order a replacement installation operation manual for my Desert Aire unit controller?

Copy your Serial Number from your unit’s rating plate and provide it when you call Desert Aire Service at 262-946-7400 weekdays 8:00am and 5:00pm CST to request a replacement manual or contact us using the service request form to obtain technical support, including ordering an Installation Operation manual for your unit's controller.

How do I reduce cost / conserve energy consumption on my energy bill for an indoor pool?
  • Use a pool cover
  • Consider installing a pool water heating unit
  • Try adjusting pool and air temperatures to adhere to traditional temp ranges of 78°F to 86°F.
How many air changes per hour should I have in a pool room?

If your state has adopted ASHRAE 62 ventilation codes, then the dehumidification system for your pool room should be designed to provide four to six air changes per hour while maintaining a relative humidity of 50 percent to 60 percent. 

Learn more in our Technical Bulletin #5: Ventilation Air for Indoor Pools.

How much condensate does a GrowAire HVAC dehumidifier unit produce?

A large Desert Aire GrowAire unit can collect up to 347.1 lbs of water an hour.  In a cannabis flower room, that would result in as much as 500 gallons of water saved per week with mature plants. That’s 71 gallons a day, 500 gallons a week, 26,000 gallons a year or a typical 18’x36’ swimming pool 4- to 8-ft deep.

Submit a request for sizing a GrowAire System at https://lnkd.in/dsBWgfWJ

How much water evaporates from an indoor pool in a year?

An indoor pool will evaporate the full volume of the pool in a year. You can calculate the evaporation of a pool, convert it to gallons and compare it to the volume of water in the pool.

What is a dehumidifier?

A refrigerative dehumidifier operates by drawing air over the evaporator coil, which transfers heat energy from the air to the refrigerant within the evaporator. As the heat energy is removed from the air, the moisture in the air condenses and the water drains into the condensate pan and down the drain. The cool, dry air passes through the reheat coil condenser and reabsorbs the heat energy from the hot gas refrigerant. The warm, dry air is discharged into the space. Heat energy can also be transferred to alternate refrigerant condensers to provide space cooling or water heating as specified.

What is a good energy conscious temperature set point range of my regular use residential indoor pool?

The rule of thumb is to maintain the air temperature 2°F above the water temperature, with an upper limit of 86°F air temperature.

The recommended temperature for a residential pool set point ranges from 78°F to 86°F.

What is the chlorine smell from in an indoor pool room?

Many people say indoor swimming pools have a tendency to smell like chlorine. This smell is actually not chlorine, but is the disinfectant byproducts of the water chlorination process. Chlorine in a pool is used to keep the pool water safe from bacteria, viruses, and other water matter that could be passed from swimmer to swimmer. The disinfectant byproducts of this water treatment results in the creation of compounds that can be harmful to the swimmers.

 

Proper ventilation of the pool room is critical in maintaining the indoor air quality. The American Society of Heating Refrigeration and Air Conditioning Engineers (ASHRAE) has established a method to establish the proper volume of outdoor air for indoor pools. However, the location of the pool room exhaust is critical in the removal of the disinfectant byproducts of the water treatment.

 

Well-designed duct work is very important and a proper exhaust location can dramatically improve the indoor air quality in a pool room.

 

To learn more, review the following documents or contact Desert Aire to assist you with improving the indoor quality for your indoor pool room.

 

Technical Bulletin #5 Ventilation Air for Indoor Pools 

Technical Bulletin #9 Interaction of Pool Water and Air Chemistry 

What is the ideal temperature and relative humidity for drying cannabis?

The ideal temperature and relative humidity for drying cannabis is between 60 and 70 degrees Fahrenheit with a relative humidity between 45% to 55%. It typically takes 5 to 15 days to dry cannabis flower depending on the temperature and humidity levels. It's important to maintain consistent environment of temperature and relative humidity throughout the drying period. 

Desert Aire’s DriCure™ Dehumidification Systems are specifically designed as an all-in-one solution for cannabis drying rooms. These commercial dehumidification systems feature scalable designs to provide drying room solutions when plants are just harvested; and then regulate humidity levels as harvested plants dry in approximately 7 to 14 days. It will handle the complete year-round dehumidification, heating and cooling needs of the room. Learn more: https://lnkd.in/eSgBdV3 View DriCure™ brochure.

What is the Penman-Monteith formula and what is it used for?

The most direct method of determining the moisture load in a grow room is to calculate the net water usage of plants. In theory this can be accomplished by measuring the volume of irrigation water added to the grow room less the volume of water that exits down the drain. The difference is the volume of moisture that is transpired or evaporated from plants and the growing system. However, this method would require the irrigation system to be in an active mode while appropriate measurement devices record data.

 

To make the calculation of sensible and latent loads more practical for the specification of grow room climate control systems, Desert Aire engineers modified a version of the proven Penman-Monteith formula.

 

The Penman-Monteith formula has evolved over the past 50 years and is an important worldwide tool in traditional outdoor agriculture for estimating evapotranspiration, the combination of evaporation and plant transpiration processes where water changes state from liquid to gas.

 

Just as agricultural engineers and scientists introduce localized data and specific crop properties or coefficients into the formula for their purposes, Desert Aire engineers modified the formula to provide a guide to estimating the latent load in a grow room space and the resultant evaporative cooling effect when exact watering rates are not known.

 

Details of the Penman-Monteith formula are beyond the scope of this FAQ. Traditionally the formula generates a reference crop value that estimates the moisture released per day for a large field of a uniform crop. To generate a reference crop value for indoor grow rooms, Desert Aire modified the formula to use a shortwave radiation value of 1.53 MJ/m2 each hour during the lights on period. For reference, this is equal to approximately 50% of the sun’s average daily total shortwave radiation at the equator. In addition the soil heat flux is set at zero since it is assumed the plants are adequately watered in an indoor grow room. Desert Aire also uses the following key variables in its calculations:

  • Net radiation of the indoor lighting systems
  • Design air temperatures of the grow rooms
  • The velocity of ventilation air at a level 3 feet about the plant canopies
  • Vapor pressure differentials

Additional key variables that impact evaporation are the actual crop canopy size at full growth, the space temperature and humidity values, and the number of hours lighting systems are on.

 

Once the reference crop value is known, then it must be converted into a rate for the particular crop being grown. Desert Aire calculates one value for emergent plants to determine the evaporative cooling credit and a second value for the peak moisture release of full-grown plants.

 

Learn more about determining the sensible and latent loads of indoor farms in our  Application Note 25: Grow Room Load Determination

What is the ph of dehumidifier condensate water?

Ph of dehumidifier condensate water is 7. It’s neutral on the ph scale.

The benefits of harvesting condensate water.

What is Vapor Pressure Deficit and why should I care about it?

Vapor Pressure Deficit (VPD) is the difference (deficit) between the amount of moisture in the air and how much moisture the air can hold when it is saturated. VPD can help an indoor grower identify healthy air moisture conditions over the full range of growing temperatures. Vapor pressure deficit correlates directly to plant transpiration rates. Using VPD to fine tune water flow through plants gives the grower another “control knob” in the quest to balance the plant environment to create a perfect day year round.

Learn more about Vapor Pressure Deficit (VPD) and how it works in relation to our GrowAire dehumidification systems in our Blog: GrowAire™ VPDsync™ Masters 4 Elements of CEA Control and our video "Desert Aire GrowAire VPDsync Environmental Control".

What would be one piece of advice to cannabis growers who are just starting out?

A: Focus on understanding your goals and what your HVACD loads are going to be. Consider:

• Number of lights needed

• Type of watering, grow media and racking

• What is the building structure type and envelop?

• Is there potential for heat infiltration into the facility?

• Will you use a harvest at once or perpetual harvest growth cycle?

• you have good air distribution? What temperature and humidity levels (VPD) will you target?

• Will you add CO2?

• What are your energy use and availability constraints?

• Where will the HVACD equipment be located?

Using the information about all these variables we can provide a tight band with respect to loads. Knowing the loads, we can select the right HVACD equipment and can provide budgetary numbers for equipment selection. 

 

Even though a cannabis facility setup is unfamiliar to a new grower or cannabis facility owner, there have been hundreds of people like you all over the country that have gone before you that Desert Aire has worked with. Desert Aire has a good idea of the type of HVACD equipment that is going to work for a cannabis grow operation, from flower rooms to mother and veg rooms to drying rooms. Desert Aire has more than 1,500 units in more than 175 indoor grow projects controlling more than 2 million square feet of indoor grow space. Contact us with your questions to learn more and let us help you with HVACD equipment selection. 

 

Read our blog “8 Grow Room Design Factors Affecting HVAC Equipment Selection

What’s the difference between a pool dehumidifier vs an air conditioner?

An air conditioner is controlled off of temperature. And that’s the key thing to understand.

Picture either a heater or an air conditioner, that says, "am I too cold or am I too hot or am I just right?" and operates to heat or cool to maintain the temperature.

 

A dehumidifier is not drawn just on temperature it’s actually focused on moisture removal.

In an indoor pool, a dehumidifier runs more of the time to remove the moisture than it does to turn on for cooling or to turn on for heating. And that’s the big operative difference is that it’s the relative humidity that is driving the dehumidifier’s compressors to turn on and off to remove moisture to maintain the environment.

 

As you’re dehumidifying the air, you’re cooling it. You don’t want to overcool the air. Desert Aire dehumidifiers have a hot gas reheat coil that captures some of the heat out of the air coming into the dehumidifier and uses it to reheat the air (reclaiming energy) from the cooling and moisture removal process before it’s exhausted from the dehumidifier to return the air to the pool room at a warm temperature.

 

In Desert Aire dehumidifiers, there is separation between temperature and humidity control.

 

Learn more at https://www.youtube.com/watch?v=AlERYCrNFs4&t=1s

When sizing dehumidifiers for a grow room with LED lighting is the amount of water going in the same as water coming out?

Regardless of lighting technology, the transpiration of the plants makes up most of the latent (moisture) load. Plants will give off roughly 90% of the water they take in through their root system back to the ambient space. Plants however do not take in all the water that is provided to them, typically there is at least 10-20% that dissipates through runoff.

When plants transpire there is an evaporative cooling effect. For every pound (16 Ounces) of water that evaporates, 1,040 BTU’s of evaporative cooling occurs. This evaporative cooling effect is present during lights on and lights off. During lights on there is also a large sensible load from the lights, but during lights off the load is latent dominant, and the evaporative cooling effect necessitates additional reheat to maintain target temps within the room.

Desert Aire's sizing and load calculation software takes the evaporative cooling effect from transpiration into account. In addition, we have developed a sophisticated multi variable algorithm that can calculate the specific transpiration rates of the plants based on a host of inputs including lighting type and density, growing media, watering strategy, and C02 supplementation rate.

 

Learn more about determining the sensible and latent loads of indoor farms in our  Application Note 25: Grow Room Load Determination

Why does an indoor pool room smell like chlorine?

This smell is actually not chlorine, but is the disinfectant byproducts of the water chlorination process. Chlorine in a pool is used to keep the pool water safe from bacteria, viruses, and other water matter that could be passed from swimmer to swimmer. The disinfectant byproducts of this water treatment results in the creation of compounds that can be harmful to the swimmers.

 

Proper ventilation of the pool room is critical in maintaining the indoor air quality. The American Society of Heating Refrigeration and Air Conditioning Engineers (ASHRAE) has established a method to establish the proper volume of outdoor air for indoor pools. However, the location of the pool room exhaust is critical in the removal of the disinfectant byproducts of the water treatment.

 

Well-designed duct work is very important and a proper exhaust location can dramatically improve the indoor air quality in a pool room.

 

To learn more, review the following documents or contact Desert Aire to assist you with improving the indoor quality for your indoor pool room.

 

Technical Bulletin #9 Interaction of Pool Water and Air Chemistry 

Technical Bulletin #5 Ventilation Air for Indoor Pools 

What causes corrosion in an indoor pool room?

When metal parts in an indoor pool room come into contact with water, chemicals such as chlorine and oxygen in the air, the metal starts to oxidize. Over time, this weakens it and creates rust. If left untreated, the rust can corrode metal to the point of creating structural damage to the pool room structure and expensive repairs or replacement. Dehumidifying the air in an indoor pool room can help prevent this structural corrosion.

What is condensation?

Condensation occurs when moist air passes over a cold surface and the water condenses from the air at a dew point temperature. A dehumidifier mechanically condenses a portion of the moisture in the air on cold coils within it, like a cold beer can getting wet from condensation. Learn more about  condensation, evaporation and dew point in our blog How 3 Key Dehumidification Terms Relate.

What is dew point?

The atmospheric temperature (varying according to pressure and humidity) below which water droplets begin to condense and dew can form. When moist air passes over a cold surface and the water condenses when it reaches its dew point temperature at the cold surface. Air can only hold so much moisture, as a function of the air temperature. Colder air can’t hold as much water vapor which condenses into water droplets at the dew point, the point that the air is saturated at 100% relative humidity. To learn more about dew point, view our blog How 3 Key Dehumidification Terms Relate.

What is evaporation?

Evaporation is simply the process of conversion of liquid water into vapor. Evaporation is a continuous process that occurs constantly outdoors in the lakes and ponds and is the reason why it rains. Evaporation is caused by the absorbance of heat from a source that will allow the conversion from a liquid to a vapor escaping a body of water.As pool water evaporates, it cools the pool water and the air in the pool room. Learn more about evaporation, condensation and dew point in our blog How 3 Key Dehumidification Terms Relate.

What is evapotranspiration?

Evapotransoration is the process by which water is transferred from plants to the atmosphere by evaporation from the plant's surfaces (usually leaves) and by transpiration from plants. It is the amount of “sweat” the plant produces that is evaporated into the air. This moisture is the real moisture load in an indoor grow room operation as it relates to the HVAC and dehumidification system. 

Why is dehumidification important to an indoor swimming pool?

Swimming pool water evaporates into pool room air. This evaporation is moisture that condenses on any surface including windows that is at or below the dew point temperature in the pool room. This condensation can lead to deterioration of the surfaces, furnishings and the building itself, and create musty odors and mold growth.

In a cannabis indoor grow room application, what is the difference between "harvest at once" and "perpetual harvest"?

In a cannabis indoor grow room application, the difference between "harvest at once" and "perpetual harvest" is as follows:

Harvest at once: plants are brought into a grow room space where they stay as they grow from young plants through the flowering process and then are harvested. Then the room is cleaned and prepped for a new batch of young plants to be brought into the room to grow until flowering stage.

Perpetual harvest: plants are moved in and out of one grow room space to another grow room as the plants grow and will not stay in the same grow room during their full period of all stages of growth. 

In an indoor grow application how does a dehumidifier know if and when the lights go out?

A dehumidifier in an indoor grow application knows if and when the lights go out using a photocell wired to the dehumidifier's control system.

How do I buy Desert Aire products?

Desert Aire markets and sells our products through manufacturers representatives. Please find your local representative by using the Find A Rep function in the Contact submenu of this website.

How do I get a price for a Desert Aire unit?

Pricing and assistance is available from your Desert Aire Representative. Please find your local representative by using the Find A Rep function in the Contact submenu of this website.

I cannot find current product information on the Desert Aire dehumidification system I am looking to replace. How can I determine if my Desert Aire system has been discontinued or is still available?

We have incorporated advances in technology and industry standards into our dehumidification systems that have led us to reconfigure and rename system offerings. The best way to meet your application needs is to contact your local Desert Aire manufacturers representative.
Please find your local representative by using the Find A Rep function in the Contact submenu of this website.

How do I install an IO Module in a Carel controller?

View the How to install an IO module video at https://youtu.be/sxzfjN4rPSQ

What is the lead time on Desert Aire products?

Desert Aire lead times vary by product line. Information on lead times is available from your Desert Aire Representative.
Please find your local representative by using the Find A Rep function in the Contact submenu of this website.

How to install a CM3530 DDC controller in a Desert Aire ExpertAire unit?

View How to install a CM3530 DDC controller in a Desert Aire ExpertAire unit video at https://youtu.be/qj0XbdnZHhA

How does a pool dehumidifier work?

A refrigeration based pool dehumidifier operates by drawing air over an evaporator coil, which transfers heat energy from the air to the refrigerant within the evaporator. As the heat energy is removed from the air, the moisture in the air condenses into water that drains into a condensate pan and down a drain. The cool, dry air passes through the reheat coil condenser and reabsorbs the heat energy from the hot gas refrigerant. The warm, dry air is discharged into the space. Heat energy can also be transferred to alternate refrigerant condensers to provide space cooling or pool water heating as specified. For swmming pool dehumidifier sizing see Application Note 10: Swimming Pool Dehumidifier Sizing for swimming pool load calculations.

How do you size a dehumidifier for an indoor pool?

To size a dehumidifier for an indoor pool you can get assistance from Desert Aire Representatives that are trained to help you select the appropriate dehumidifier for your application.

Answers to the following questions are needed at a minimum to properly determine the best Desert Aire solution for your poolroom application:
1. What is the surface area of each pool or whirlpool within the poolroom?
2. What is the square footage of the poolroom?
3. What is the average ceiling height of the poolroom?
4. What is the temperature at which each pool will be maintained?
5. What is the temperature at which the poolroom will be maintained?
6. Is there a separate spectator area as part of a larger space?

In addition, see our Technical Application Note #10 about Indoor Pool Dehumidifier Sizing.  

How do you size an industrial dehumidifier?

Sizing an industrial dehumidifier involves establishing the project design conditions by answering questions and considering several factors: what is the best temperature and humidity for the application? After the design dry bulb temperature and humidity level has been established, check what the dew point is of these two conditions. What is the moisture load? After the worst case load is calculated the equipment is selected based on 100% of the calculated load or less. Other considerations include the size of the space, amount of outside air introduced, lowest temperature, existence of a vapor barrier and open liquid tanks. Desert Aire has developed a sizing tool that will calculate the moisture load of many industrial applications. The method used is based on the ACCA Manual N and ASHRAE formulas. Our Tech Bulletin 29 explains the information required and considerations for sizing an industrial dehumidifier. 

What refrigerants are used in Desert Aire dehumidification systems?

Desert Aire dehumidification systems use either R-410A or R-407C.

What is HFC Phasedown?

The Kigali Amendment to the Montreal Protocol establishes a global structure for the phasedown of hydrofluorocarbons (HFCs). Under the amendment, countries committed to cut the production and consumption of HFCs by more than 80 percent over the next 25 years. The phasedown puts a maximum cap on the production of new, virgin refrigerant, so the only way to keep old machines operational will be to reclaim the old refrigerant. 

For more information about the HFC Phasedown, read our blog HFC Phasedown. New Refrigerants Coming.

Where can I get help in selecting an appropriate unit for my application?

Desert Aire Representatives are trained to provide application assistance for any application.
Please find your local representative by using the Find A Rep function in the Contact submenu of this website.

Are your dehumidifiers EnergyStar Rated?

Desert Aire dehumidifiers are not EnergyStar rated since the EnergyStar program does not cover the systems we build. The current EnergyStar program for dehumidifiers is limited to the free standing portable type (non-ducted) with compressor sizes less than 12,000 Btu/hr or less than 2 lb/hr of moisture removal. This program was an offshoot of the AHAM rating program for home appliances.

The EnergyStar program has not provided a rating system as of yet for the large systems that require more fan motor horsepower to overcome the static of supply and return air duct work. AHRI has created two standards to rate the moisture removal efficiency of larger dehumidifiers and Dedicated Outdoor Air Systems: AHRI 910 and 920 respectively are available from the ahrinet.org website.

How does switching from HID lighting to LED lighting in a grow room affect the HVAC system?

The switch from HID to LED is the most common change. The biggest difference between HID and LED is the LED lighting produces significantly less radiant heat. Comparing the leaf temperature of a room with HID and LED lights shows the room with HID lights has leaf temperatures of 3-4 degrees F higher than the room temperature. The room with LED lighting will have leaf temperatures of 2-3 degrees lower than the room temperature. The reduction in leaf temperatures with LED lighting allows growers to raise the room temperature slightly.

 

The reduction in radiant heat in grow rooms with LED lighting results in the ability to raise the room temperature slightly.  The benefit of this is the DX system’s latent moisture removal capacity while reducing the sensible cooling in the room. One of the key factors in a lighting change is the corresponding change in temperature and humidity set points. The performance of HVACD systems is greatly impacted by the lighting choice and set points. Always review every room condition calculation when making a change in plant count, lighting, watering or anything in a cultivation room and determine how it affects the HVACD system, its capacity, settings, and performance.

What is a chilled water dehumidification system?

Chilled water dehumidification uses cold water from a chiller generally below 42F° (16°C) as the fluid to remove moisture from an airstream.  As the air is cooled below saturation, water is condensed out of the air.  The colder the water the more moisture can be removed. Learn more about GreenAire™.

When or why would I specify a chilled water dehumidification system?

One advantage of a chilled water system is it is generally easier to plumb water piping than it is refrigerant piping. Recovered energy can be easily be reused in all parts of a facility. Chillers have a better energy efficiency.

One disadvantage is the chiller/air handler system will be more expensive than a D/X refrigeration based system. Learn more about GreenAire™.

What is the difference between a D/X dehumidification system and other types of dehumidification system?

Most dehumidifiers use a refrigerant direct expansion (D/X) technology that the airstream flows across. The refrigerant makes the evaporator coil very cold and then condenses water from the air moving over it.  This technology is used for 45% to 65% relative humidity targets. 

Desiccant wheel systems use a specialty absorption type of wheel to remove humidity in applications requiring low humidity ranges below 40% RH.  After the water is absorbed by the wheel it rotates to second air stream that uses heat to remove the water.

What size grow canopy and HVAC load can a chilled water air handling system be used with?

In concept, a chilled water system can be used in any size facility.  However, the cost to install and maintain for small facilities is not normally practical.

In general, facilities larger than 100,000 square feet with demands greater than 200 to 300-ton cooling load or larger will consider chilled water systems. Learn more about GreenAire™.

Can a natural gas chiller be used with GreenAire?

Natural gas chillers provide both the chilled water and hot water necessary for the GreenAire to function. These types of chillers also help reduce the electrical connect load for the facility. Learn more about GreenAire™.

What kind of chillers can be used with a GreenAire system?

Desert Aire’s GreenAire system can use any type of chiller that produces water below 42°F (16°C) and heat recovery chillers, absorption chillers and natural gas chillers. Learn more about GreenAire™.

What is a heat recovery chiller?

A heat recovery chiller uses the internal refrigerant to capture some or all of the waste heat and use it to heat a second water loop up to 100°F to 120°F (37°C to 49°C) for use by the GreenAire™ system.

While it is important for a design engineer to calculate the exact hot water load, a general rule of thumb is only 50% of the chiller must be used for heat recovery, lower its cost. 

Can a redundant chiller design be incorporated into a GreenAire system?

It is highly recommended to use a minimum of two or three chillers for the facility providing redundancy. These chillers can be plumbed together to be used for the entire facility. A design subset of chillers are modular chillers which can be sized to provide many layers of redundancy. Learn more about GreenAire™.

Why do I need a dehumidifier for my poolroom?

Pool water evaporates into poolroom air. This evaporation is moisture that condenses on any surface including windows that is at or below the dewpoint temperature in the poolroom. This condensation can lead to deterioration of the furnishings and the building itself, musty odors and mold growth.

Why can't I just use outdoor air to remove moisture from a poolroom?

Using only outdoor air for your poolroom ventilation can be expensive and makes it difficult to control a poolroom's humidity level, and the rate of evaporation from the pool surface. In some areas, outdoor air will often contain more moisture than the air inside the poolroom. Introducing humid outdoor air only increases the moisture content of the air inside the poolroom where it condenses on surfaces that are cooler than the dewpoint temperature. This condensation can lead to deterioration of the furnishings and the building itself while causing odors and promoting mold growth.

Conversely, introducing outdoor air that is too dry into a poolroom can accelerate evaporation of the pool water. In addition to the expense of adding water and water treatment chemicals to the pool, the accelerated evaporation makes swimmers feel chilled when their skin quickly dries upon leaving the water. Desert Aire dehumidification systems provide optimum control of humidity in your poolroom environment to safeguard the comfort and health of building users; protect furnishings and building systems; and conserve energy, water and water treatment resources.

Which Desert Aire dehumidification system should I choose for my poolroom application?

Several Desert Aire dehumidification systems are available for poolroom applications. For help in sizing and choosing the system that is best for your needs, please contact a Desert Aire Representative. To find your local representative, please use the Find A Rep function in the Contact submenu of this website.

What dehumidification system is best for large indoor pools, aquatic centers and natatoriums?

Desert Aire's SelectAire and SelectAire Plus dehumidification systems are specified for large indoor pools, aquatic centers and natatoriums. Desert Aire SelectAire (SA) Series systems are flexible in their design options and can be customized for specific applications. For example, SA Series systems can be installed indoors or outdoors; equipped with or without energy recovery systems; and equipped with or without outdoor air box systems for ventilation air.  

Desert Aire SelectAire Plus (SP) series can be applied to the same types of installations but has enhanced features for energy efficiency and control.  In addition to the unique heat-pump type energy recovery of all SelectAire systems, the SP series has double-wall foam-injected casing, self-balancing direct-drive plenum fan arrays for both supply and exhaust, and a wrap-around heat-pipe for enhanced moisture removal efficiency among many other enhanced features.

What information is needed to size a poolroom dehumidifier?

Desert Aire Representatives are trained to help you select the appropriate dehumidifier for your application. Answers to the following questions are needed at a minimum to properly determine the best Desert Aire solution for your poolroom application:
What is the surface area of each pool or whirlpool within the poolroom?
What is the square footage of the poolroom?
What is the average ceiling height of the poolroom?
What is the temperature at which each pool will be maintained?
What is the temperature at which the poolroom will be maintained?
Is there a separate spectator area as part of a larger space?

At what temperature should a poolroom be maintained?

As a general rule, the temperature should be maintained at about 2° F above the water temperature. It is Desert Aire's recommendation that the air temperature should not be above 86° F.

At what relative humidity level should a poolroom be maintained?

It is recommended that the relative humidity be maintained at between 50% and 60% in the poolroom.

Why should I use an outdoor air box on a poolroom dehumidifier?

Outdoor air is introduced into a dehumidification system after the evaporator coil for several reasons. During the winter cold outdoor air may cause condensation in return air at undesirable places in the system or ductwork. Also, the variability of the outdoor air will influence the design and performance of the evaporator coil. When colder outdoor air mixes with the return air from a poolroom, it lowers the mixed air conditions that flow over the evaporator coil. This lower condition reduces the capacity of the system and creates a variable, unpredictable moisture removal and cooling capacity. To eliminate these issues, Desert Aire’s outdoor air box introduces the outdoor air between the evaporator and hot gas reheat coil.

Where are ExpertAire Series dehumidifiers used?

ExpertAire Series dehumidifiers are used wherever excess humidity is a problem. Common applications include residential and hotel poolrooms, water treatment and wastewater treatment plants, records storage areas, warehouses and manufacturing facilities.

In what temperature conditions can an ExpertAire Series dehumidifier be used?

ExpertAire dehumidifiers are designed to operate in air temperatures between 65° and 95° F (18° to 35° C).

How much moisture can an ExpertAire dehumidifier remove?

ExpertAire Series dehumidifiers are available in a range of sizes designed to remove between 8 lbs/hour and 84 lbs/hour of moisture from the air at ARI standard 82° F / 60% RH. Your Desert Aire Representative is available to assist you with unit selection for your application.

Does the ExpertAire Series meet AHRI 910?

Yes. ExpertAire Series dehumidifiers are compliant with AHRI's moisture removal efficiency (MRE) requirement for indoor pool applications.

Can the ExpertAire Series dehumidifier introduce outdoor air?

Yes. The ExpertAire Series dehumidifiers are available with an outdoor air intake option.

What is a DOAS?

DOAS is a dedicated outdoor air system. DOAS are used to introduce outside air into a space as specified by the mechanical design engineer. In many areas local building codes require that outdoor air be brought into the building to help improve indoor air quality for occupants.

Unfortunately, outdoor air can also introduce moisture into a facility and can create IAQ problems such as mold, mildew and an environment where viruses and other organisms can flourish. The key to preventing mold formation and IAQ problems is to control the humidity level inside the building. While a standard air conditioner is thermostat controlled to provide space cooling, it cannot accurately control the humidity levels.

Desert Aire's answers to this problem are our Aura™, VerticalAire™ and TotalAire™ systems, which are designed to introduce 100% outdoor air while precisely controlling space humidity and temperature levels.

Please contact your local Desert Aire Representative for help in selecting the Aura™, VerticalAire or TotalAire DOAS system that is best for your application.

Do Desert Aire's DOAS solutions meet AHRI 920 and ASHRAE 90.1 energy minimums?

Yes. All of Desert Aire DOAS solutions comply with AHRI's moisture removal efficiency (MRE) requirements and significantly exceed ASHRAE 90.1 2013 minimum energy efficiency ratings.

Where are SP Series dehumidifiers installed?

The SP Series units were designed to be an extremely high efficiency climate control unit tailored to large indoor pool facilities such as natatoriums or waterparks.  Other applications where high levels of dehumidification are possible if target air conditions are similar.

What makes a SelectAire Plus (SP) different from a SelectAire (SA) unit?

The SelectAire Plus design leverages the additional 25 years of innovation in design and manufacturing capabilities to increase the energy efficiency, ease of use, and environmental control.  The SP has an alternate airflow and coil arrangement to continue to provide the extremely effective energy recovery of the SelectAire system while eliminating the possibility of bypass air from the outdoor to the exhaust.  The SP also includes a wrap-around heat pipe to increase dehumidification capacity and efficiency.  

The combination of the SelectAire energy recovery and the enhanced dehumidification of the SelectAire Plus (SP) is a patent pending design. 

How does the SP increase the energy efficiency?

The SP Series unit contains two refrigeration circuits.  One is optimized for dehumidification, the other is optimized for heat recovery and cooling.  The control logic in the machine senses the space requirements and shifts the operation of each circuit and the airflow in the machine to use the most efficient methods to condition the space. 

Direct drive fan arrays, scroll compressors, and heat exchangers that use the refrigerant directly to exchange energy with the air are also important to reducing energy use.  

What refrigerant do SP dehumidifiers use?

R-410A refrigerant

How does the SelectAire Plus system compare to a system that uses both refrigerant and water/glycol for cooling or heating?

Some equipment manufacturers divert the refrigerant gas to and air-to-water heat exchanger then move that water to another water to air heat exchanger to condition the air.  Although it may be easier to design a system this way, it is much less efficient.  The compressor needs to work harder since it is more difficult to transfer the energy.  There are also additional pumps, valves, control, and heat exchangers to fail.  The SelectAire Plus is designed to directly exchange the energy from the refrigerant heat exchangers to the air.  This reduces complexity and increases energy efficiency.  

What makes the SP unit so easy to install?

Dampers and fans are self-balancing and are factory programmed for the flow rates at the time of order.  Commissioning consists of reviewing the flow rates programmed on the units display terminal and ensuring that the field-installed ductwork allows the airflow programmed.  

SP Series units are available in packaged air-cooled models up to the SP80 model size. This is an industry exclusive.

How is the LW Series dehumidifier different from a standard dehumidifier?

Typical dehumidifiers work best in high ambient temperature conditions of between 65 to 95 degrees F (18 to 35 degrees C) and 50 to 80% relative humidity while the LW Series dehumidifiers are designed to operate in low temperature applications of 32 to 70 degrees F (0 to 21 degrees C).

In what sizes is the LW Series dehumidifier available?

The LW Series dehumidifiers are available in sizes ranging from 3 to 15 nominal tons.

Are sectioned SP systems available to allow for longer crane lifts or installation through tight spaces indoors?

All SP Series units come as a completely assembled system.  Only the longest units that will not fit on a drop-deck flatbed in one piece have a filter section that needs to be easily connected in the field (no refrigeration work!).  

Optionally, the units can come in several sections that allow for lower weight per section and smaller size.  These are pre-designed sections that have been specifically created to allow for minimized cost and field labor.  See the General Arrangement drawings for the size and weight of the optional sections.  

Specially designed sectioned systems are available for extreme cases.  Contact your Desert Aire Representative for more details.

What refrigerant is used in the LW Series dehumidifiers?

R-407C refrigerant

When would I specify an LW Series dehumidifier?

The LW Series units are for low temperature applications ranging from 32 degrees F to 70 degrees F (0 to 21 degrees C).

Why doesn't the LW Series dehumidifier have problems with freezing?

To prevent the evaporator coil from freezing in low temperature conditions, the LW Series dehumidifiers are designed with a timer that will initiate the defrost cycle when the suction line temperature drops below 30 degrees F (-1 degree C). During the defrost cycle the blower is disengaged and all of the system's reheat capacity is diverted to the evaporator, where it quickly thaws the coil. Once the suction line temperature increases to confirm the evaporator coil has thawed, the dehumidifier can resume normal operation.

Are exploded view drawings available?

Due to the wide variety of configurations, exploded view drawings are not presently available.

How do I order replacement parts?

Call Desert Aire's Service Department at 1-262-946-7400 weekdays between 8:00 am and 5:00 pm Central time.

Can I get replacement parts shipped overnight?

With the exception of compressors, we can generally ship in-stock parts for next day delivery when the order is placed before noon. Expedited freight charges are at the customer's expense.

How do I start a warranty parts claim?

Call Desert Aire's Service Department at 1-262-946-7400 weekdays between 8:00 am and 5:00 pm Central time.

What number do I call for Desert Aire Service?

Call Desert Aire's Service Department at 1-262-946-7400 weekdays between 8:00 am and 5:00 pm Central time.

Where can I get an Installation & Operation Manual?

To download Installation & Operation Manuals, go to the Service & Support area of this website and click on Installation & Operation Manuals.

Where can I get the wiring diagram?

Call Desert Aire's Service Department at 1-262-946-7400 weekdays between 8:00 am and 5:00 pm Central time.

What is the Psychrometric Chart?

A psychrometric chart shows physical and thermal properties of moist air on a graph where dry bulb temperatures, a humidity ratio (moisture content) scale, is shown as vertical lines and the horizontal lines show the dew point temperatures or the saturation temperature at which a vapor changes into liquid or condensation.  Learn more about the psychrometric chart in our Technical Bulletin#3

How do I load or update a program to a controller?

To load or update a program to a controller, follow the instructions in this video.

How do I need to prepare the existing Desert Aire R-22 remote outdoor condenser for use with R-410A?

Using an existing Desert Aire R-22 remote condenser with a Desert Aire replacement R-410A dehumidifier is strictly dependent upon which model of Desert Aire remote condenser you're currently utilizing. If the existing remote condenser cannot be used, a new one must be purchased from Desert Aire. The following is a list of all Desert Aire basic remote outdoor condenser models and indicates whether they're compatible with one of our R-410A systems.

Model RC: No.

Model ROC: No.

Model ROCF: Yes.

Model ROCH: Yes.

Model ROCQ: Yes.

Please note that the R-22 systems use different refrigeration oil than R-410A and therefore all traces of oil and R-22 refrigerant must be removed prior to conversion to R-410A.

Can I use my existing line sets when replacing a dehumidifier that uses R-22 refrigerant with a dehumidification system that uses R-410A refrigerant?
In order to reuse line sets the following must be reviewed: 
1. The diameters of the line set must be adequate for the new appliance.
2. The line set must be Type K or Type L copper in order to withstand the higher pressures of R-410A refrigerant.
3. Brazing materials should be compliant with R-410A. If unknown the line set must be replaced. 
4. The line set must be properly flushed/cleaned of previous refrigerant & oil. 
 
Desert Aire recommends that a Line Set Analysis be completed prior to the appliance installation to determine if the line set can be reused. In most cases new line sets will be required. Please consult Desert Aire Service for any questions.
Can I use an existing Desert Aire R-22 remote condenser with a Desert Aire R-410A replacement dehumidifier?

Using an existing Desert Aire R-22 remote condenser with a Desert Aire replacement R-410A dehumidifier is strictly dependent upon which model of Desert Aire remote condenser you're currently utilizing. If the existing remote condenser cannot be used, a new one must be purchased from Desert Aire. The following is a list of all Desert Aire basic remote outdoor condenser models and indicates whether they're compatible with one of our R-410A systems.

Model RC: No.

Model ROC: No.

Model ROCF: Yes.

Model ROCH: Yes.

Model ROCQ: Yes.

Please note that the R-22 systems use different refrigeration oil than R-410A and therefore all traces of oil and R-22 refrigerant must be removed prior to conversion to R-410A.

What is AireGuard?

AireGuard™ is Desert Aire’s remote monitoring and alarming tool that allows a user to easily monitor the performance of the dehumidifier on a cloud-based database at any computer or portable device. All that is required is an Ethernet Internet connection directly to the Desert Aire operating controller.

 

Information security is maintained since this is a cloud based system where the client computer only accesses the remote data servers. The unit controller transmits data to and from the cloud storage location. Communication at the controller takes place on port 80, the same port that any computer uses to communicate with the web. The existing LAN firewall is maintained and no action from the IT department is required as long as the facility has internet access.

 

Users log onto the cloud-based service to view and interact with data. No further access to your local network is required. This connection will meet all of your IT department’s security requirements. LC, LV, and LCQ Series products have an onboard Ethernet connection as standard.

 

The AireGuard interface easily brings the read and write variables in real time to the display screen. It allows the user to adjust set points remotely as well as monitor all the operating variables.

 

The Desert Aire LC/LV/LCQ Series have another feature that allows the local display interface to be duplicated on the cloud based interface. This feature allows for remote startup capabilities by Desert Aire employees.

 

Since the refrigeration system of a dehumidifier is very complex, many owners hire outside firms to maintain their HVAC units. The alarm management feature of AireGuard provides the owner with email or SMS notifications at time of occurrence. With appropriate access to the Desert Aire dehumidifier unit via the cloud, the servicing contractor or Desert Aire may be able to evaluate the unit’s alarm with corrective action without visiting the site.

 

AireGuard is included with each LC/LV/LCQ unit and includes a two year subscription to the cloud data storage. Renewal subscriptions can be purchased after expiration.

View the AireGuard brochure

Can I monitor my Desert Aire unit's performance remotely?

Yes, Desert Aire units are available with AireGuard, Desert Aire's remote monitoring and alarming tool that allows a user to easily monitor the performance of the dehumidifier on a cloud-based database at any computer or portable device.

 

Information security is maintained since this is a cloud based system where the client computer only accesses the remote data servers.

 

Users log onto the cloud-based service to view and interact with data. No further access to your local network is required. This connection will meet all of your IT department’s security requirements. LC, LV, and LCQ Series products have an onboard Ethernet connection as standard.

 

The AireGuard interface easily brings the read and write variables in real time to the display screen. It allows the user to adjust set points remotely as well as monitor all the operating variables.

 

The alarm management feature of AireGuard provides the owner with email or SMS notifications at time of occurrence. With appropriate access to the Desert Aire dehumidifier unit via the cloud, the servicing contractor or Desert Aire may be able to evaluate the unit’s alarm with corrective action without visiting the site.

 

AireGuard is included with each LC/LV/LCQ unit and includes a two year subscription to the cloud data storage. Renewal subscriptions can be purchased after expiration. View the AireGuard brochure.