EXAIR Cabinet Coolers vs. Air to Air Heat Exchangers

At EXAIR we’ve been providing enclosure cooling solutions for decades, and in many cases those cooling solutions have remained in place for decades as well.  In the time we’ve been in the market with industrial enclosure cooling solutions we’ve encountered a number of alternative means for enclosure cooling.  One of those methods is an air-to-air heat exchanger.

heat exchanger 1
Heat exchanger

An air-to-air heat exchanger uses the temperature differential between the ambient air surrounding an enclosure and the hot air inside an enclosure to create a cooling effect.  A closed loop system exchanges the heat inside the enclosure with the outside air in an effort to maintain a set internal temperature.  The heat exchange of most air-to-air unit relies on a heat pipe, a heat-transfer device which converts an internal refrigerant liquid into vapor by placing one end of the pipe in contact with the hot environment.  The heated vapor travels to the other end of the pipe which is in contact with a cooler environment.  The vapor condenses back into a liquid (releasing latent heat) and returning to the hot end of the pipe and the cycle repeats.

But, this type of a solution does give some cause for concern, especially when considering their use in an industrial environment.  Here are the key points to keep in mind when comparing an air-to-air cooler to an EXAIR Cabinet Cooler.

Cabinet Cooler Family
EXAIR Cabinet Coolers

Required temperature differential based on ambient air temp

An air-to-air heat exchange relies on the ΔT between the ambient air temperature and the internal enclosure air temperature to produce cooling.  If this ΔT is low, or the ambient temperature rises, cooling is diminished.  This means that as the temperatures in your facility begin to rise, air-to-air heat exchangers become less and less effective.  Larger air-to-air heat exchangers can be used, but these may be even larger than the enclosure itself.

EXAIR Cabinet Coolers rely on the ΔT between the cold air temperature from the Cabinet Cooler (normally ~20°F) and the desired internal enclosure temperature (normally 95°F).  The cold air temperature from the Cabinet Cooler is unaffected by increases in ambient temperatures.  The large ΔT and high volume cold air flow produced by a Cabinet Cooler results in more cooling capacity.  And, we can increase cooling capacity from a Cabinet Cooler without increasing its physical footprint, which is already much, much smaller than an air-to-air type of unit.

 

Cooling in high temperature environments

Due to their nature of operation, an air-to-air heat exchanger must have an ambient temperature which is lower than the desired internal temperature of the enclosure.  If the ambient air has a higher temperature, air-to-air units provide zero cooling.

Cabinet Coolers, on the other hand, can be used in hot, high temperature environments up to 200°F (93°C).

EXAIR's High Temp Cabinet Cooler Systems
High temperature Cabinet Coolers

 

Cooling in dirty environments

Dirt in the ambient environment will impact cooling performance with an air-to-air heat exchanger.  In order for the air-to-air unit to effectively remove heat, the heat pipe must have access to ambient air.  With any exposure to the ambient environment comes the possibility for the ambient end of the heat pipe to become covered in ambient contaminants such as dust.  This dust will create an insulation barrier between the heat pipe and the ambient air, decreasing the ability for the heat pipe to condense the vapors within.  Because of this, most air-to-air devices use filters to separate the heat pipe from the ambient environment.  But, when these filters become clogged, access to ambient temperatures are reduced, and cooling capacity of the air-to-air unit reduces as well.

Cabinet Coolers have no problem operating in dirty environments.  In fact, it is one of their strengths.  Without any moving parts to wear out or any need to contact ambient air for cooling purposes, a dirty environment poses no problems.  In fact, check out this blog post (and this one) about EXAIR Cabinet Coolers operating maintenance free for years in dirty environments.

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NEMA 12 Cabinet Cooler in a Dirty Environment

Size and time required to install

Air-to-air heat exchangers vary in size, but even the smallest units can have large dimensions.  Many applications have limited space on the enclosure, and a large, bulky solution can be prohibitive.  Couple this with the time and modification required to the enclosure to install a large air-to-air unit, and the “solution” may end up bringing additional problems.

Another key aspect of the Cabinet Cooler is its size.  Small, compact, and easy to mount on the top or side of an enclosure, Cabinet Coolers install in minutes to remove overheating problems.

 

Heat within an electrical cabinet can be a major issue for manufacturing companies. The costs associated with down time and repairs on sensitive electronics that fail due to heat or environmental contaminants, are an unnecessary burden. If you have any questions about how an EXAIR Cabinet Cooler can solve problems in your facility, contact an EXAIR Application Engineer.

Jordan Shouse
Application Engineer
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Cabinet Cooling with Thermostat Control and ETC

An EXAIR Cabinet Cooler® System with either the Thermostat Control or the Electronic Temperature Control (ETC) option includes a temperature measuring device that is used to control the operation of the Cabinet Cooler System to maintain the set-point temperature.Thermostat and ETC

For most industrial enclosure cooling applications, a temperature of 95°F (35°C) is sufficient to be below the rated maximum operating temperature of the electrical components inside the cabinet. EXAIR Thermostats are preset to 95°F (35°C) and are adjustable. Maintaining the cabinet at 95°F (35°C) will keep the electronics cool and provide long life and reduced failures due to excessive heat. But if 95°F (35°C) is good, why not cool the cabinet to 70°F (21.1°C)?

When cooling an enclosure to a lower temperature, two things come into play that need to be considered. First, the amount of external heat load (the heat load caused by the environment) is increased. Using the table below, we can see the effect of cooling a cabinet to the lower temperature. For a 48″ x 36″ x 18″ cabinet, the surface area is 45 ft² (4.18 m²). If the ambient temperature is 105°F (40.55°C), we can find from the table the factors of 3.3 BTU/hr/ft² and 13.8 BTU/hr/ft² for the Temperature Differentials of 10°F (5.55°C) and 35°F (19.45°C). The factor is multiplied by the cabinet surface area to get the external heat load. The heat load values calculate to be 148.5 BTU/hr and 621 BTU/hr, a difference of 472.5 BTU/hr (119.1 kcal/hr)

External Heat Load

The extra external heat load of 472.5 BTU/hr (119.1 kcal/hr) will require the Cabinet Cooler System to run more often and for a longer duration to effectively remove the additional heat. This will increase, unnecessarily, the operating costs of the cooling operation.

The other factor that must be considered when cooling an enclosure to a lower temperature is that the Cabinet Cooler cooling capacity rating is effected. I won’t go into the detail in this blog, but note that a 1,000 BTU/hr Cabinet Cooler (rated for 95°F (35°C cooling) working to cool a cabinet down to 70°F (21.1°C) instead of 95°, has a reduced cooling capacity of 695 BTU/hr (174 kcal/hr).  The reduction is due to the cold air being able to absorb less heat as the air rises in temperature to 70°F instead of 95°F.

In summary – operating a Cabinet Cooler System at 95°F (35°C) provides a level cooling that will keep sensitive electronics cool and trouble-free, while using the least amount of compressed air possible.  Cooling to below this level will result in higher operation costs.

If you have questions about Cabinet Cooler Systems or any of the 15 different EXAIR Intelligent Compressed Air® Product lines, feel free to contact EXAIR and myself or any of our Application Engineers can help you determine the best solution.

Brian Bergmann
Application Engineer
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Special Cabinet Cooler Options – High Temperature, Non-Hazardous Purge and Type 316 Stainless Steel

Recent blog discussions about the EXAIR Cabinet Cooler Systems have covered many topics including correctly sizing one, the NEMA ratings, and how-they-work.  In this blog I will review three special options that are available for the most extreme environmental conditions- high temperatures, dirty environments, and harsh or corrosive areas.

High Temperature – For enclosures that reside in high temperature ambient conditions such as near furnaces, boilers, or ovens, EXAIR offers a High Temp version, with special internal components designed to withstand the elevated temperatures.  Cabinets near sources of high heat certainly need to be kept cool, and the EXAIR High Temperature Cabinet Cooler is specially suited to for use in these locations.

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High Temperature Dual Cabinet Cooler System

Non-Hazardous Purge (NHP) – Cabinet Cooler Systems with this feature provide a continuous positive purge within the enclosure to prevent contaminants from entering through small holes or conduits.  Especially suited for dirty and dusty environments, the NHP Cabinet Cooler Systems provide a slight positive pressure inside the enclosure. This is done by passing 1 SCFM (28 SLPM) of air through the cooler when the the solenoid is in the closed position. When the thermostat reaches the set-point temperature and energizes the solenoid, the full line pressure of air is delivered to the Cabinet Cooler providing the full cooling capability, and still keeping the positive pressure.  When the internal temperature cools to the set-point, the solenoid closes and the system returns to the 1 SCFM (28 SLPM) of air flow condition.

nhpcc_300x
Non-Hazardous Purge Cabinet Cooler for Dirty, Dusty Environments

Type 316 Stainless Steel NEMA 4X Cabinet Coolers – For enclosures that are in food service, pharmaceutical, harsh, and/or corrosive environments, and any application where 316 stainless steel is preferred, the Cabinet Coolers are available in the Type 316 stainless material. The systems are UL Listed for wash down environments, ensuring the enclosure electrical contents remain cool and dry under any condition. Noted applications include on ocean going ships, power plants, medical device manufacturing facilities, and bakeries.

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Type 316 Stainless Steel NEMA 4X Cabinet Cooler System

Please note that the High Temperature, Non-Hazardous Purge and Type 316 Stainless Steel Cabinet Coolers are each available from stock!  No waiting for these special models.

To discuss your application and how a Cabinet Cooler System or any EXAIR Intelligent Compressed Air Product can improve your process, feel free to contact EXAIR, myself, or one of our other Application Engineers. We can help you determine the best solution!

Brian Bergmann
Application Engineer

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EXAIR’s Cabinet Coolers Solve Your Overheating Problems

We here at EXAIR always know when summer is approaching, as phone calls and orders for the Cabinet Cooler Systems start to kick into high gear.  After those first few hot days in late spring, it is common for panels and electrical enclosures to overheat due to faulty air conditioning units, fans that are not working, or lack of a cooling system in general.

Time for us to sharpen our pencils and be ready to help! Our Cabinet Coolers are in stock and ready to solve your overheating problems with same day shipping on orders we receive by 3pm. If you need assistance choosing your Cabinet Cooler Solution, Contact an Application Engineer today!

The Cabinet Cooler System is a low cost, reliable way to cool and purge electronic control panels.  We recently hosted a Webinar on the systems, and it is available for review (click picture below)  webinar-on-demand

EXAIR Cabinet Coolers incorporate the vortex tube technology to produce cold air from compressed air, all with no moving parts.

Below shows the basics of how the Cabinet Cooler is able to provide cooling to an enclosure.  Compressed air enters the vortex tube based system, and (2) streams of air are created, one hot and one cold. The hot air is muffled and exhausted through the vortex tube exhaust.  The cold air is discharged into the cabinet through the Cold Air Distribution Kit and routed throughout the enclosure. The cold air absorbs heat from the cabinet, and the hotter air rises to the top of the cabinet where it exits to atmosphere under a slight pressure. Only the cool, clean, dry air enters the cabinet – no dirty, hot humid outside air is ever allowed into the cabinet!

HowCCWorks
How the EXAIR Cabinet Cooler System Works

EXAIR offers Cabinet Cooler Systems for cabinets and enclosures to maintain a NEMA rating of NEMA 12 (dust tight, oil-tight), NEMA 4 (dust tight, oil-tight, splash resistant, indoor/outdoor service) and NEMA 4X (same as NEMA 4, but constructed of stainless steel for food service and corrosive environments.

Cabinet Cooler Systems can be configured to run in a Continuous Operation or with Thermostat control. Thermostat control is the most efficient way to operate a Cabinet Cooler.  They save air by activating the cooler only when the internal temperature reaches the preset level, and are the best option when fluctuating heat loads are caused by environmental or seasonal changes. The thermostat is preset at 95°F (35°C) and is easily adjusted.

Another option is the ETC Electronic Temperature Control, a digital temperature control unit for precise setting and monitoring of enclosure conditions. An LED readout displays the internal temperature, and the use of quick response thermocouple provides real time, accurate measurements. The controller has easy to use buttons to raise or lower the desired cabinet temperature set-point.

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EXAIR NEMA 4X 316SS Cabinet Cooler System with Electronic Temperature Control installed on control panel in a pharmaceutical plant.

 

Other Special Cabinet Cooler considerations are:

  • High Temperature –  for ambient temperatures of 125°F to 200 °F – for use near furnaces, ovens, etc.
  • Non-Hazardous Purge – ideal for dirty areas where contaminants might normally pass through small holes or conduits. A small amount of air (1 SCFM) is passed through the cooler when the solenoid is in the closed position, providing a slight positive pressure within the cabinet.
  • Type 316 Stainless Steel – suitable for food service, pharmaceutical, and harsh and corrosive environments.

If you have any questions about Cabinet Coolers or any of the EXAIR Intelligent Compressed Air® Products, feel free to contact EXAIR and myself or one of our Application Engineers can help you determine the best solution.

Brian Bergmann
Application Engineer

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Expand Flexibility of Cabinet Coolers with Side Mount Kits

Last week I wrote about the Thermostat Options for Smart Cooling utilizing the EXAIR Cabinet Cooler Systems.  You can see read that blog post here.  Today we will touch base on the Side Mount Kits as an option to expand the flexibility for the installation and operation.

Sometimes there isn’t room above an electrical panel to fit the Cabinet Cooler, even though it takes just 5″ to 7.25″ of space above. In these cases, the Side Mount Kit is available to handle any of the Cabinet Cooler sizes and NEMA ratings. EXAIR offers (6) models of Side Mount Kits –

  • Model 4909 – For NEMA 12 Cabinet Coolers up to 550 BTU.hr (139 Kcal/hr), Aluminum construction
  • Model 4910 – For NEMA 12 Cabinet Coolers , 650 BTU//hr (165 Kcal/hr) and higher, Aluminum construction
  • Model 4906 – For NEMA 4 and 4X Cabinet Coolers up to 550 BTU/hr (139 Kcal/hr), Type 303 Stainless Steel
  • Model 4907 – For NEMA 4 and 4X Cabinet Coolers, 650 BTU/hr (165 Kcal/hr) and higher, Type 303 Stainless Steel
  • Model 4906-316 – For NEMA 4 and 4X Cabinet Coolers up to 550 BTU/hr (139 Kcal/hr), Type 316 Stainless Steel
  • Model 4907-316 – For NEMA 4 and 4X Cabinet Coolers, 650 BTU/hr (165 Kcal/hr) and higher, Type 316 Stainless Steel

side_mounts_new

The NEMA 4 and 4X Cabinet Coolers must be mounted vertically for the unit to properly resist the ingress of liquids and maintain the integrity of the cabinet NEMA rating.

The Side Mount Kits install into a standard electrical knockout (1-1/2 NPS) for easy installation.

If you have any questions about the Side Mount Kits, Cabinet Coolers and/or Thermostat Options or any of the EXAIR Intelligent Compressed Air® Products, feel free to contact EXAIR and myself or one of our Application Engineers can help you determine the best solution.

Brian Bergmann
Application Engineer

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Electrical Cabinet Cooling with EXAIR Cabinet Cooler System

If you watched the Webinar we hosted recently (if not, Watch It here) then you know that the EXAIR Cabinet Cooler System is an intelligent solution for electrical enclosure cooling.  The use of a Thermostat Control system is a key component to a system that provides the needed cooling while keeping compressed air usage to a minimum. There are several choices available, and I will cover those for you today.

The thermostat control systems are the most effective way to operate a Cabinet Cooler. They work by activating the the cooler only when the internal temperature of the enclosure reaches a preset, critical level. Thermostat controlled cooler systems are the best option when a cabinet will experience fluctuating heat loads, caused by operational, environmental, and seasonal changes.

Cabinet Cooler Systems that are ordered from the factory with thermostat control include a solenoid valve and thermostat.  The solenoid valve is available in 110-120VAC, 50/60 Hz, 240VAC, 50/60 Hz, and 24VDC and is UL Listed and CE and RoHS compliant. The thermostat is rated for 24V-240V AC or DC, 50/60 Hz and is UL Recognized and CSA Certified.

Solenoids
Solenoid Valves – 24 VDC, 110 VAC, and 240 VAC Available

 

The thermostat is factory set at 95°F (35°C). It will typically hold an internal cabinet temperature to +/- 2°F (1°C). The thermostat can be adjusted up or down if a different internal temperature is desired by turning the slotted temperature adjusting sleeve, with a 1/16 turn being approximately a 5°F change.

9017_thermoPRINT
Thermostat

 

The solenoid and thermostat components are rated to match and maintain the Cabinet Cooler System and cabinet NEMA rating, and can be NEMA 12, NEMA 4 or NEMA 4X. A Thermostat Control can be added to an existing Continuous Operation Cabinet Cooler System, please consult the factory for help in selecting the right kit.

4825SS
NEMA Type 4X Cabinet Cooler System, which includes the Solenoid Valve and Thermostat

If you have any questions about the Cabinet Coolers and Thermostat Options or any of the EXAIR Intelligent Compressed Air® Products, feel free to contact EXAIR and myself or one of our Application Engineers can help you determine the best solution.

Brian Bergmann
Application Engineer

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EXAIR’s Cabinet Cooler System is Durable and Reliable

Any realtor will tell you that the three most important factors in selecting a property are location, location, and location. This simply means that houses with similar features – number of bedrooms, yard size, structure, garage (or not,) basement or not,) etc. – can be found in a lot of very different neighborhoods. Whether you want to live somewhere that’s convenient to the highway, close to (or not so close to) work, near your favorite activities, etc., odds are you can find a house that meets your material needs & wants within those geographical confines. Hence, location is your #1 consideration. And your #2 and your #3 as well…my lovely bride is a real estate professional, so I have this on good authority. And, so you know, #4 is price, and #5 is condition.

Electrical and electronics controls professionals will tell you that three of the most important things to protect their equipment from are heat, moisture, and dust. If you’re looking for a durable, reliable, and low cost method for that, we’ve got the solution: the EXAIR Cabinet Cooler System. Selection of the right system comes down to determining your heat load, and…the reason for today’s blog…the LOCATION in which it will be installed.

Let’s say it’s a control panel for one of the machines on a factory production line…indoors & dry.  Our NEMA 12 Cabinet Cooler Systems provide protection against dust and oil from entering the enclosure.

NEMA 12 Cabinet Cooler Systems are oil tight, dust tight, and rated for indoor duty. They can also be installed to the wall of an enclosure (instead of the top) with a Side Mount Kit.

If the enclosure is outdoors, or indoors but subject to water spray (like in a wash-down area,) our NEMA 4 Cabinet Cooler Systems are oil tight, dust tight, AND splash resistant.  They ensure the inside of the enclosure stays dry through the use of a low pressure relief valve that seals when the cooler is not operating, maintaining NEMA 4 integrity at all times.

EXAIR NEMA Cabinet Cooler Systems provide additional protection to keep the enclosure dry inside.

Our NEMA 4X Cabinet Cooler Systems are made of stainless steel, and are commonly specified for food service area installations, and in corrosive environments.  They’re also oil tight, dust tight, and splash resistant.  These are also available in Type 316 Stainless Steel construction, for especially harsh conditions, or when this is otherwise specified due to the nature of the installation, such as critical food grade or pharmaceutical areas.

EXAIR NEMA 4X Cabinet Cooler Systems are made of corrosion resistant stainless steel for corrosive environments, and are also available with Side Mount Kits.

Regardless of the NEMA rating called for by the location, all EXAIR Cabinet Cooler Systems are available with a Non-Hazardous Purge option, which provides a slight positive pressure through a low (1 SCFM) air flow when internal temperature is below the thermostat setpoint and the solenoid valve is closed.  This provides constant and reliable protection, even if the enclosure is not perfectly sealed, even in especially dirty or dusty environments.

All EXAIR Cabinet Cooler Systems are available with Non Hazardous Purge for constant, reliable protection from environmental contaminants.

High Temperature Cabinet Cooler Systems are also available when ambient temperatures can exceed 125F.  These are popular in foundries, glass production facilities, and even non-air conditioned spaces in particularly warm climates.

High Temperature Cabinet Cooler Systems provide reliable heat protection in areas where ambient temperatures reach 125-200F (52-93C)

If you’ve got sensitive, mission-critical electrical or electronic enclosures that need reliable heat protection, EXAIR has the solution you’re looking for.  If you know the required cooling capacity for your enclosure, you can select the right system directly from our website.  If you’d like help in calculating your heat load, you can use our Cabinet Cooler System Sizing Guide…just fill in the blanks and click “submit” – your request will be forwarded to an Application Engineer for immediate attention.  Or, if you’d rather, just give me a call.  We calculate heat loads over the phone all the time; it only takes a minute.