Thought energy from the people at Virtjoule

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As a young company, we’re still learning the range of things that are possible with the Virtjoule solution.  In the last year and a half, we’ve discovered that not only has the technology met our original vision of functionality and price, the types of projects that can be accomplished are even more varied than we thought.  The Virtjoule solution has been installed on everything from beverage coolers to a 6,000 ton cooling system on a major Las Vegas hotel.

We often get asked, “What kind of projects can you do?”  In the earlier days of the company, the answer was in the form of suggestions of what we ought to be able to do.  After all, we had a device that could pick up vibration and the ability to track that vibration over time and see patterns emerge.  

These days, the answer is educated by field experience with the problems and the economics of solving those problems for our customers.  At the highest level, the answer is “If it vibrates, we can monitor it.”  As a company, we’ve done work in the various segments you’ll see in the list below.

To get a handle on the range of applications, perhaps it’s useful to take a scan across the types of units that we’re currently tracking.

Function Model
Beverage Coolers Micro Matic MMPP4301
Walk-in refrigeration Numerous models of Harford Duracool
Harford Duracool – H1984A8
Trenton – TEHA025L6-HS2A-F – 2.5 hp
Trenton – TEHA006E6-HS2B-B – .6 hp
Air conditioning – Split systems Ducane – 2AC13L60P – 2A – 5 ton
Package units Trane YSC048A3EMA2U – 4 ton
Trane YSC060A3EMA3 – 5 ton
Rheem RKKA-A073CL10E – 6 ton
Carrier – 48TCEA07A2A5A0A0A0
Bard PH13062
Bard PH1060-B – 4.6 ton
York D1NA042N05625C – 3.5 ton
York D1EB048A25B – 4 ton
York D2NA060N09025D – 5 ton
York DM090N10A2AAA4B – 7.5 ton
York BP090C00A2AAA4A – 7.5 ton
York D1EB060A25B – 5 ton
Johnson Controls – J05ZJN10D2AAA1C – 5 ton
Johnson Controls – J07ZHN15P2AAA4B – 7.5 ton
Johnson Controls – J10ZHN20S2AAA4B – 10 ton
Johnson Controls – J25ZJN32S2BZZ10001 – 25 ton
York ECO2 50 ton
Carrier 48P5 Horizontal VAV 100 ton
McQuay 40 ton
McQuay 70 ton
Heat pump packages and split systems Heil Tempstar – NHP060AKC1 – 5 ton
Coleman/York – HP060X1021A, 5 ton split system
Goodman CKL60-1 – 4.75 ton
Goodman CPLE60-1 5 ton
Goodman GPH1324M41AB 2 ton
York 20 ton
CRAC-(Computer room air conditioners) Liebert
Evaporative Coolers – Water pumps Can’t divulge manufacturer at this time
Air handlers Goodman AH120-00
Commercial Refrigeration Compressors Copeland Copelametic 4RA3-100A-TSK-800
Copeland Copelametic 6RA4-200A-TSK-800
Copeland Discus 3DB3F33KE-TFC-800
Copeland Discus 4DL3F63KE-TSK-800
Chillers York – 18 ton
Carrier 30GTN090 90 ton
Cooling towers Baltimore Air Coil, 125 hp electric pump and 100 hp VFD fan – 2,000 ton

One of the most satisfying things that we’ve seen is that this is a huge range of equipment, all being monitored by the same Virtoule Sense technology.  

If you’re familiar with some of the pieces on this list, you’ll know that some put off so much noise and vibration that you need ear protection.  Other pieces are so quiet and smooth that it’s very difficult to tell if they’re running when standing right next to them or even putting your hand on the machine.  I’ve been particularly impressed with the Trane series (YSC060A3EMA3) as very smooth operators in package units.

Because the Virtjoule sensor is self-calibrating, once it’s installed it can start off as a very sensitive device and self calibrate to the point where it can handle large magnitude vibrations.   This self-calibration means that the installation is roughly the same for all of these installations, stick it on, power it up, and start getting data.  An operating signature will always emerge that can be analyzed, reported on, and alerted on.

Customer and facility types

The table above is specific to equipment and equipment applications.  But what sort of customers and markets does this represent?  Here’s one look at the type of facility and customer:

  1. Executive office buildings
  2. Restaurants
  3. Strip malls
  4. Small market and convenience store refrigeration
  5. Data centers
  6. Hotels

Some are very high energy users where control problems or equipment degradation can cost thousands of dollars a year if the problem isn’t corrected. Some have equipment that might not burn a lot of energy, but the unit is serving high value contents. Food, pharmaceuticals, and computers are good examples of high value contents that need to be protected from catastrophic loss.

In a recent example, Virtjoule was able to give the owner of a walk-in refrigerator days of notice that their unit was degrading. The customer was able to get a refrigerant leak fixed before they lost control of the temperature of the cooler. One of my upcoming blog articles will discuss this “catch”.

If I were to sum up our results since we started, I would say we’ve helped customers save money by identifying control problems or system degradation that were racking up extended hours and energy bills. And we’ve helped some customers avoid serious loss of high value contents that were being refrigerated.

What new applications will we see this year? I can’t wait to find out.

[Randy Cox - CEO and co-founder of Virtjoule - He has been the software designer and analytics engineering for Virtjoule Sense sensors. He studied Chemical Engineering and Petroleum Refining at the Colorado School of Mines. You may contact Randy at: randy at virtjoule dot com]


Refrigeration is a critical component of any restaurant for a variety of reasons, not the least is the health and safety of its customers.  Keeping a close eye on how that refrigeration is working is key to avoiding health concerns and potentially the loss of all the contents of a walk-in cooler.  In this article you will see how easy it is to notice that a walk-in refrigeration condenser unit is beginning to malfunction.

Key concepts:

  • Most any kind of fault will disrupt the observable common pattern of how the condenser unit operates.
  • Condenser faults may build up over time wasting energy and working equipment harder before a total failure occurs.
  • There can be adequate time to get a faulty unit fixed before it completely fails if the behavior change caused by the fault is detected.
  • Quick visual inspection of Virtjoule charts to compare patterns can easily identify changes in behavior that need to be investigated.

We recently notified a customer of a behavior change that we observed in the walk-in refrigerator for their restaurant.  This is a critical unit for the restaurant as it’s the condensing unit for the only walk-in refrigerator that they have at this site.  As you will see in this article, it’s not hard to figure out that something had radically changed in the operation of this unit despite the fact that the temperature in the cooler hadn’t risen.  It was just a matter of time before this unit would have failed causing a big problem for the restaurant owner and the manager.

The walk-ins for this restaurant chain are made by Harford Duracool.  Their labels don’t last in the sun and so I don’t have the exact model number for this condenser unit.  The photo below is of the actual unit that failed.

Harford Duracool walk-in refrigerator condenser unit

Harford Duracool walk-in refrigerator condenser unit

What I want you to note in the following graphic is just how easy it is to determine that the unit has broken out of it normal pattern.  This could be done visually or by using the Virtjoule cycle counter which would have shown a radical drop in the number of full cycles that occurred.  The green and red highlights are mine.

You can see that just before 10:00 am on October 30, this unit stopped doing full cycles and ran continuously until about 4pm where it shut down for a few minutes and then started back up with an intense series of cycles only shutting down once every 5-6 hrs.  Clearly this is much different than the cycles you see on the left hand side of the chart.  The unit is working much more aggressively and constantly.

Harford Duracool Condenser breaking into failure pattern

Harford Duracool Condenser breaking into failure pattern

The unit wasn’t fixed right away and luckily there was not a catastrophic failure that would have required moving or throwing away the food in the cooler.  You can see this same failure pattern continued for quite some time.

Harford Duracool condenser in failure mode

Harford Duracool condenser in failure mode

Finally, about 9am on November 11th, the unit was shut down.  It was thawed out, condenser cleaned, and then restarted just after 10:30 am.  It ran continuously for a while in order to catch up on its cooling, but then settled back into its normal cycle rhythm about 6pm.  It has been running normally ever since.

Harford Duracool condenser failure fix

Harford Duracool condenser failure fix

In conclusion, you can see that it’s not at all difficult to notice that there was a problem developing and it was also quite easy to see when the problem was resolved.  Virtjoule didn’t diagnose what the problem was, but it gave enough warning time for the unit to be looked at, fixed, and restarted before a catastrophic failure occurred.  There was no other type of monitoring being done on this unit and it would have completely failed leaving the cooler to warm up at an inopportune time (night, food inspector dropping by, etc.).  Compared to that inconvenience, a call to the Harford Duracool dealer and service was all it took to get things working well again.