Virtjoule is proud to announce the availability of cellular HVAC and refrigeration monitors!  With nearly a year of experience in the field with the cellular version of our monitors, all of our current customers have been converted from the short range radio based monitors.  No longer will you need a netbook computer somewhere within radio range.  No longer will you be at the mercy of the Internet connection at remote locations.

The vision we had when we started the company over three years ago is now finally a reality.  That is, “parachute” onto a building, stick on and power up a sensor and begin collecting machine runtime data immediately and remotely without expensive installations, capital expense, or expensive integration projects with building automation systems.

Key Points

- Sensor comes already activated on one of the nation’s leading cellular providers:  Click here

- All sensors are independent of each other.  No more mesh network and the possibility of one weak link bringing down the whole sensor network.

- Even easier install.  New sensor is polarity independent, running on any power source from 12 VDC to 24 VAC.  A standard RTU can be installed in less than 10 minutes.

- New web application features including automated short cycle fault detection.

- Built-in internal cellular antenna.  External magnetic mount and direction antenna options are available for those really difficult locations.

- New, smaller, and lighter weight vibration microphone.  Tape and screw mount options available.

Virtjoule Cellular HVAC Monitor

Virtjoule Cellular HVAC Monitor

The back story

When the first versions of Virtjoule HVAC monitors were developed over three years ago, they communicated over a low power and short distance radio network.  This was the only way to create an economical sensor that could be applied to such a wide range of equipment, everything from large 125 hp pumps and fans on huge cooling towers to small beverage coolers.

Since that time a quiet revolution was taking place in what is now called “Machine to Machine” (M2M) applications.  Cellular carriers like Verizon, AT&T, and many others were aggressively developing their growth plans and decided that much of their strategy would depend not on selling more handset devices, but selling more lines for sensors, tablets, and all sorts of devices that needed internet connectivity.  Suddenly the price to acquire a cellular internet connection for a single device became an order of magnitude lower.

Virtjoule always knew that the mesh network radio based approach was an initial architecture.  We didn’t know how or when we would be able to transition that architecture to fulfill our original vision.

Certified cellular device

One year ago, Virtjoule became a certified device for one of the nation’s leading cellular providers.  We were approached by our business account representatives and the M2M specialists and we discussed moving Virtjoule to cellular.  This was a process that took months of development, negotiations, learning, and investment.  Since that certification, we have rolled out this new cellular sensor to all of our customers.

Say “No!” to obsolescence

A huge benefit to the Virtjoule way of monitoring is that no one actually buys the sensor.  It is included in the monthly service cost.  No Virtjoule customer was left holding an obsolete piece of equipment.  We simply replaced everything in the field with our newest model and we all moved forward together.

If you’re ready for the advantages of true 24/7/365 HVAC and refrigeration monitoring that is independent of the local tenant or building internet connections, then get in touch with us so we can tell you how you can start today!  Call 1-800-658-1864 or click on the contact link to tell us about yourself.

[Randy Cox - CEO and co-founder of Virtjoule - He is the software designer and analytics engineer 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]

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It’s hard to imagine where control of our indoor environments would be without the lowly thermostat. Programmable thermostats have been a mainstay of both commercial and residential heating and cooling.  But like the VCR “Blinking Twelve Problem”, the proliferation of thermostat interfaces has caused many to be completely misunderstood.  Property owners and tenants ignore the thermostat to their own detriment.  

This article discusses a client who was heating and cooling 24/7 on two of their Carrier HVAC units for a retail store in a small strip mall.  The cause was mis-programmed Carrier Debonair thermostats.  They had no idea.  Without the HVAC monitoring capability of Virtjoule, this condition may have gone unnoticed for years.

Upon properly programming the thermostat, the units are now running just 12% of the time they were running before.

Carrier is a big and trusted name in HVAC, without a doubt.  But that hasn’t solved the problem of complex programming interfaces for mere mortals.  I have a 29+ year career working with computers and the interfaces on most thermostats can still be mind boggling.  This store was using a Carrier Debonair thermostat.  Within the Debonar lineup there are no less than 10 models to choose from.  The model our client had was similar to this one:

Carrier Debonair thermostat

Carrier Debonair thermostat

Since this client was very close to where I live, I took the opportunity to go check on it myself.  First thing I did was to go on the Internet and find the owners manual for this model.  I was able to find it here:

As is often the case, I was expecting that there would be some schedule problem or perhaps a misunderstanding about what happens when the fan mode is set to “On”.  After all, we’ve seen that there is no predicting what the blower is actually doing when the heating and cooling mode is set to “Off” or even “Auto”.  We’ve seen blowers continue to run when the thermostat mode is set to “Off” and it is thermostat dependent.  Very counter intuitive, but who is going to go on the roof or hold a tissue in the air stream to notice if the blower is running after you shut down for the night?

What I found on this thermostat is that it has three different occupancy programming modes.  The first and default mode, Occupancy 1, has the unique feature that the occupancy schedule can be overridden by a light sensor.  That was a red flag to me as that means the thermostat was depending on yet another sensor which might or might not be working, rather than the building schedule that it also contains.  It could also be getting confused by other inputs like street lights through windows and start times would change radically depending on what time of year it was.  Why would you want that if the building hours are nearly identical throughout the year?

Without enough time or a good way to determine if the light sensor was working, it was clear to me that a retail establishment like this should not be depending on light to control its space.

Switching the thermostat to “Occupancy 2″ mode allowed it to be controlled by the occupancy schedule.  On this thermostat each day has occupancy times and unoccupied times.  Luckily there is a feature that allows you to copy one day to the next, but how you do that is completely inscrutable if all you had was your eyes on the thermostat.  It took some careful reading of the owners manual to figure that out.  By the way, where do you think the owners manual was on site?  I don’t know either.

Besides the occupancy mode issue, both thermostats had their time and day set wrong.  In the case of this seven day a week establishment, having the day set wrong was harmless.  But here in February, both clocks were still set to daylight saving time.

Let’s take a look at the results.  During this time the temperatures here in Colorado were temperate with daytime highs in the 40′s and 50′s and lows in the mid-20′s.  The first image is a typical daily runtime graph of one of the units before the thermostat change.  The blower was running 24/7 punctuated by cycles of heat.  There was simply no schedule on this unit and it was always running.

Runtime before thermostat change

Runtime before thermostat change

The “after” chart is one that is much easier on the eyes.  You can see some periodic runtime during the night when the setback temperature of 58 was hit.  But by late morning there was no runtime at all.  So not only was the tenant saving night time and after hours runtime, the majority of their savings was actually achieved during business hours when outside air and activity in the building was working for them.

Runtime after thermostat change

Runtime after thermostat change

 Across the two units, I was able to compute that total runtime after the thermostat change was just 12% of what it was before.  That’s what you call saving money.  Without HVAC monitoring of these units, this money would have been wasted month after month.

[Randy Cox - CEO and co-founder of Virtjoule - He is 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]

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A Trane Tracker controlled office and warehouse building had a rogue schedule, resulting in a HVAC bill that was 20 percent higher than necessary for the tenant.  The building had 10 roof-top units (RTU’s), including one CRAC (Computer Room Air Conditioning) unit and nine package units.  In addition to running during normal operating hours, all nine RTU’s were showing runtime on Saturdays — when the building was unoccupied.  Neither the owner nor tenant were aware of the issue.  Simply put, these machines were operating 20 percent longer than needed which not only led to higher HVAC expense for the tenant but, ultimately, would have shortened the lifetime of the equipment, reducing the property owner’s ROI.

Although BAS (Building Automation Systems) can streamline and help control a big facility, mistakes in BAS programming are often compounded — or missed altogether — without monitoring tools.    As buildings with BAS get passed from tenant to tenant and HVAC service to HVAC service, valuable knowledge is often lost as to how the BAS and subsequent schedules were set up.  It can be tedious and expensive to recommission the building and do a full audit of schedules within the BAS.  Until there is a complaint, these sort of problem situations can drag on for months or years,  wasting energy and money.

Key Concepts

  1. Mistakes in BAS programming can be magnified across a building system, resulting in higher than necessary expenses, and still not be readily apparent.
  2. Programming of BAS, if properly done, has benefits for both the property owner and the tenant(s).
  3. Many BAS, if not most, lack the kind of internal monitoring controls that can uncover these money-wasting mistakes.
  4. BAS systems are complicated and system knowledge is often lost when new tenants move in or when HVAC services are switched.

The facility we were working on is a typical high tech office building with an attached warehouse area.  It has a total of 10 units, one Trane Voyager used as a CRAC unit and 9 other Trane Voyagers of various vintages.  All the units that we were monitoring were on the roof of the building.

BAS controlled building running after hours

Two story office, one story warehouse space

Soon after Virtjoule’s HVAC monitoring sensors were installed on the Trane Voyagers, it became apparent that there was a scheduling problem with the building.  All the units would start up on Saturday mornings at, but not exactly on, their normal weekday hour.  The slightly different start time was the first clue that an extra schedule was in the system.  Shutdowns were often at the same time as the weekday schedule for each unit.

This is a professional building with product developers and executives and featuring some manufacturing and warehouse space.  Although employees can come in on the weekend, there is no need for the building to be completely heated or cooled for just a few people.  Employees do have access to thermostats to regulate heating or cooling if they wish.

The building engineer was alerted and initially puzzled by the situation since he thought the building should be in “unoccupied mode”.  He proceeded to work carefully through the BAS system and located the rogue schedule.

Because the rogue Saturday schedules were so similar to the weekday schedule, it’s easy to see that the owners of this facility have now reduced the wear and tear on the equipment they own by one day a week — or 52 days a year!  The tenant is saving over 16 percent on their HVAC expenses (having paid 20% more than they should have) and presumably, over a longer period of time, will save on maintenance as the number of calls should decrease.

[Randy Cox - CEO and co-founder of Virtjoule - He is 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]

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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]

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This is the second post of a two post series demonstrating the flexibility and simplicity of installing our sensors.

Answers to the questions from the first post (Part 1)

- How many sensors do you think our system would need to monitor a system this large? Only 6 sensors to monitor this entire cooling tower system!

- How to keep the sensors from getting destroyed in a harsh environment? All sensors are sealed in UV and water resistant plastic enclosures.

Rugged Sensor

- Where do you place the sensors and not interrupt building operations? Since they are installed with industrial strength tape and are non intrusive they can be place almost anywhere, that means no equipment down time or service disruption.

These pictures shows the microphone attached directly to the cooling tower fan housing, no penetrations required!

Fan Housing Sensor Attached to Housing

- Doesn’t the system already have an energy management system?

These towers are monitored with the latest technology from Tridium (Honeywell Controls). Even with all this technology we found lots of opportunities for improvement from load balancing to reducing VFD hunting.

- How long did it take us to install our system? Only 2 hours for 2 people!

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