The Negative Effect of Hot Ambient Conditions on Traditional A/C Refrigerant Panel Coolers vs EXAIR Cabinet Coolers

EXAIR’s High Temp Cabinet Cooler Systems

As summer endures and temperatures continue to rise panel conditioning units can start to struggle to keep your electronics cool.  An agricultural company contacted EXAIR as they were having some issues with their air conditioning panel cooler.  The increase in outside temperatures caused the air conditioning systems to underperform.  The electronics were overheating and shutting down production.  They needed a better way to keep the internal circuits cool during the hotter months of summer. 

They sent in the information on the A/C panel that they were using (reference photo below).  I circled the important factors that we would need.  EXAIR is familiar with these tags as we helped many customers to find a more reliable way to keep their electronics cool.  This customer stated that they had already replaced three units in the past 10 years.  The one above has been in operation for only 3 months, and they were still worried about failure.  It could be due to lack of maintenance, dirty environment, or high ambient temperatures, but the short life of the refrigeration units was a major concern. 

From the placard, the total cooling capacity was DIN EN 14511 L35 L35 0.38KW as circled above.   The DIN EN 14511 is a European Standard that rates the performance of air conditioning units.  The first L35 is the temperature rating for inside the panel, 35oC.  The second L35 is the ambient temperature, 35oC.  The cooling capacity at those temperature conditions is 0.38KW, or 1,296 BTU/hr.  As you can see, the performance was measured with the ambient temperature at 35oC (95oF).  If the ambient temperature goes above this standard rating, the cooling capacity of the air conditioning unit will start to decrease.  With the EXAIR Cabinet Cooler Systems, we use the internal temperature as 35oC (95oF) as well, but our external temperature can be as high as 93oC (200oF).  Here is a diagram showing the range of the different types of cooling devices as compared to the ambient temperatures and the environment.

Another note on the placard is the IP Code – IP54; and “Maintains the environmental integrity of type 12”.  EXAIR offers three different NEMA ratings to keep the integrity of your panel.  We offer NEMA 12, NEMA 4 and NEMA 4X.  The rated voltage for the A/C panel cooler is 115 V / 60 Hz / 1-.  EXAIR offers three different voltages with our solenoid valves to work in conjunction with our thermostats.  We have 240Vac, 115Vac, and 24Vdc.  So, from the information supplied by the A/C panel cooler, we are getting close for a recommendation.  What do we need next?  The ambient temperature condition which affected the A/C panel cooler.  I need this information to calculate the heat load on the hottest day of the hottest month. 

In the Cabinet Cooler Sizing Guide that we sent to them; they marked the “Maximum external temperature possible” at 130oF (54.4oC).  As seen in the chart below, this is the upper limit for the performance conditions for an A/C unit.  With the EXAIR Cabinet Cooler System, we can offer a High Temperature Cabinet Cooler that can work up to 200oF (93oC).  And, they will still operate under the harshest of environments.  With the size of their panel, the external heat load was calculated at 980 BTU/hr.  Remember, since we are replacing the A/C panel cooler with an EXAIR Cabinet Cooler System, we will need to add the 0.38KW or 1,296 BTU/hr to the external heat load.  The total heat load is measured at 980 BTU/hr + 1,296 BTU/hr = 2,276 BTU/hr

Since we now have all the information, I recommended a model HT4340 Cabinet Cooler System.  This system has a NEMA 12 Cabinet Cooler, a filter, a cold air distribution kit, a thermostat, and a 115Vac solenoid valve.  The cooling capacity for the HT4340 is 2.800 BTU/hr; above the required 2,276 BTU/hr maximum heat load.  So, when the internal temperature reaches 95oF (35oC), the thermostat will turn the solenoid off to save compressed air.  This Cabinet Cooler System fit the criteria as noted on the placard on the A/C unit for replacement. 

HT4340 Cabinet Cooler System

With they received the model HT4340, they were amazed at how small and compact the unit was.  The Cabinet Cooler does not have any moving parts, Freon, or condensers to clean.  They only need clean compressed air.  The installation was also very simple.  It took them longer to remove the A/C unit than to install the EXAIR Cabinet Cooler.  They were able to start using the Cabinet Cooler in less than one hour.  They also commented to me about how they wished that they knew about the Cabinet Cooler Systems 10 years ago.  The breakdowns, the replacements, the maintenance, and the headaches that the A/C units delivered cost them much money in material and production shutdowns. 

If you have electrical panels over-heating or air conditioning units under-performing, you should try an EXAIR Cabinet Cooler System.  You can fill out the Cabinet Cooler Sizing Guide and an Application Engineer will find the best model to keep your operations running; even during the summer months. 

John Ball
Application Engineer
Email: johnball@exair.com
Twitter: @EXAIR_jb

Non-Hazardous Purge Cabinet Coolers Prevent Process Disruptions for a Garbage Company

Non Hazardous Purge

A garbage facility opted to start a preventative maintenance program.  They looked at different areas that would create potential problems and stoppages within their processes.  One issue was the over-temp faults with their Variable Frequency Drives, VFDs, during the summer months.   VFDs control the speed of motors and in a garbage facility, many motors are used for pumping, conveying, and sampling.  When the internal temperature rises above the specification for the VFD, the system will trip and stop the motor from running.  In this type of industry, delays are very costly.  They wanted a way to prevent this from happening. 

They contacted EXAIR because they were interested in our electrical cooling concept; the EXAIR Cabinet Cooler System. They generate cold air with no moving parts.  They do not use any Freon or motors to operate; and they require very little to no maintenance.  They only need clean dry compressed air to work.  I sent the Cabinet Cooler Sizing Guide for the general questions to correctly size the Cabinet Cooler for each electrical panel.  When they went to check the temperatures inside the cabinets, they noticed that the electrical components were dirty and dusty (reference photo below).  This directed our conversation to another type of Cabinet Cooler System; the Non-Hazardous Purge System.  Being that the environment was very dirty, the dust particles were able to get into every little crevice, crack, and slits where the wires were entering and exiting the electrical panels.  With dirt and dust particles, this would create issues with the efficiency, effectiveness, and potential safety in the filthy electrical components.   

An option that we discussed was the EXAIR Non-Hazardous Purge (NHP) Cabinet Coolers.  This product is designed to continuously bleed about 1 SCFM (28 SLPM) of compressed air into the cabinet.  A slight positive pressure is created to keep any ingress of dust particles from getting into the electrical cabinet.  EXAIR offers the NHP models from 275 BTU/hr (69 Kcal/hr) to 5,600 BTU/hr (1,411 Kcal/hr) cooling capacities.  From the heat load calculations for the panel above, they needed a model NHP4340 which has 2,800 BTU/hr (706 Kcal/hr) cooling capacity. This size would keep the internal temperature less than 95oF (35oC) even during the hottest day of the hottest month.

The Non-Hazardous Purge Systems accomplish two things:  keep the electrical components cool during heavy operations and warm temperatures; and keep the electrical components dust free.   With this type of complete system, it will also include the thermostat control to save on compressed air during non-peak times and cooler months.  Now that I shared the maintenance program from this garbage company, you can review your electrical panels to determine any short-comings with summer approaching.  If you have any questions, you can contact an Application Engineer at EXAIR.  We can help you to keep your facility from getting into a hot “stinking” mess with shutdowns.      

John Ball
Application Engineer
Email: johnball@exair.com
Twitter: @EXAIR_jb

Electrical Panel Heat Protection: Limitations of Fan Cooling

In preparation for some labor-intensive outdoor projects, I did some research into heat-related health risks, and their prevention. My first thought on prevention was getting someone else to do it, but my wife made a good case for “pride in ownership”, and I DO have a good many tools suitable for these projects. Also, I am notoriously frugal, so after getting a couple of estimates, I realized the value in a little DIY (do it yourself) and commenced planning.

High on that list of risks was the possibility of heat stroke. It’s recommended that the victim be taken to a cool space (someplace air conditioned, for example). Air flow (like from a fan) can help too, but only if they’re taken someplace where the ambient temperature is less that 95F (35C). If it’s that hot, the air flow can actually make things worse, since heat transfer requires a difference in temperature. If the cooling medium (air, in this case) is the same temperature as the object to be cooled (the human body, in this case), no heat will be transferred – and the heat stroke wins. That’s a bad day in the back yard.

This is, in fact, the exact same limitation with a popular method of electrical panel cooling: fans. We’ve been using mechanical methods of imparting motion to air for cooling purposes for a long, long time: Blowing on a spoonful of soup or a cup of coffee before a warm (but not scalding) sip, waving hand fans at oneself during indoor gatherings, installing electric fans in those same buildings, and the list goes on. Fans are inexpensive to purchase & operate, come in a variety of sizes & configurations, and are oftentimes used to circulate cooling air through occupied rooms, confined spaces, and, of course, electrical & electronic panel enclosures.

These are quite effective for panels with moderate-to-high internal heat loads, as long as the ambient area temperature is less than the temperature you wish to cool the panel’s internal air to. In those situations, the only real concern is the quality of the air in the environment. As you can see in the photo to the right, filters are an absolute “must”, and they’re going to require regular maintenance. This means cleaning or replacing the filters, as well as cleaning the fan grills and blades themselves. It’s still very likely that some of that dust is going to get inside the enclosure, and while we’re on the subject of environmental contamination, so will humidity. I probably don’t need to tell you that dirt and/or water, and electricity, don’t mix.

There are other methods of cooling (panel a/c, thermoelectric coolers, water cooled heat exchangers, heat pipes, etc.) that limit environmental contamination, but they’re still going to need periodic (oftentimes frequent) attention: filters will clog, refrigerant coils will get fouled and corrode, moving parts will wear, motors & switches will burn out, etc. Even with the advances made in refrigerant technology, the leaks that panel a/c and heat pipes are prone to are still bad for the environment.

If this sounds like your environment, and you’re looking for safe, dependable, durable heat protection, look no further than EXAIR Cabinet Cooler Systems. Using the Vortex Tube phenomenon, they generate cold air from your compressed air supply, with no moving parts to wear or electric devices to burn out. Systems are on the shelf & ready to ship in cooling capacities to 5,600 Btu/hr. We also “tailor-make” systems for higher heat loads, from stock products, that can usually ship right away as well. Once installed on a sealed enclosure, the only thing the internals of that enclosure are ever exposed to again is clean, moisture free, cold air. All of our Cabinet Cooler Systems come with an Automatic Drain Filter Separator – the only preventive maintenance that’s ever required for the systems is the periodic replacement of the filter’s particulate element.

Inside, outdoors, high temperature, dirt/dust/humidity, corrosive and classified environments are no problem for EXAIR Cabinet Cooler Systems

We can quickly and accurately specify a Cabinet Cooler System to meet your needs with just a few key pieces of information – you can fill out a Sizing Guide (or complete one online) and send it in to us, or you can call an Application Engineer with the data. It only takes a minute to do the calculations, and we do them over the phone all the time. Installation is straightforward and usually only takes a matter of minutes. We have a number of short “how to” videos on our website that cover all aspects of installation, and if you ever have specific questions or concerns, an Application Engineer is a phone call away. We look forward to hearing from you!

Russ Bowman, CCASS

Application Engineer
EXAIR Corporation
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Hazardous Location AND Overheating Electronics? We Have You Covered!

Here in Ohio, we like to think we know a lot about the weather. Did you know there are more than 4 seasons? Heck, we have at least two Winters, and then a Pre-Summer, Spring, Summer, Heat is still coming – make it stop season, and Fall. Don’t forget the construction season where the lovely orange cones and barrels bloom on every major roadway, and then we also like to throw in brood weeks for the cicadas every now and then. Yeah, we get a full gambit of weather and the past week has brought out some heat. I know this isn’t just Ohio, we get calls from around the globe of atmospheric conditions that have caused issues within control panels. Some of these panels are in areas where the No Smoking sign is more than just a suggestion to better your health.

1 – Dust Explosion

That’s right, there are areas in manufacturing facilities that are governed by the standard due to a variety of conditions resulting in what is known as Hazardous Locations. NFPA and UL have a list of standards breaking these down into separate Classes, Divisions, and Temperature Classes. If you want all the details, the NFPA code is around 908 pages, cover to cover. The Classified UL mark shown below is one way of knowing that a product has been tested to these stringent standards and is okay to use in clearly marked environments.

UL Classified Markings

EXAIR offers Cabinet Cooler Systems that will meet these stringent standards and keep your enclosures cool in order to keep your production up and running. The top three tiers that we meet are:

  • Class I Div 1, Groups A, B, C and D
  • Class II Div 1, Groups E, F and G
  • Class III

The HazLoc Cabinet Cooler Systems are available in 8 different cooling capacities from 1,000 Btu/hr to 5,600 Btu/hr. and are manufactured to work in conjunction with a purged and pressurized control system. As well as with or without thermostatic control.

EXAIR’s Hazarous Location Cabinet Cooler Systems maintain Type NEMA 4/4X Integrity and are CE Compliant.

If you would like help sizing the correct system for your electrical panels, feel free to use the link, or contact an Application Engineer to discuss the applications and get one sized while on the phone with us.

Brian Farno
Application Engineer
BrianFarno@EXAIR.com
@EXAIR_BF

1 – Dust explosion 05.jpg, Hans-Peter Scholz, October 7, 2009, retrieved from https://commons.wikimedia.org/wiki/File:Dust_explosion_05.jpg