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Ahr2023 Succession

An Update on Service Benchmarking

Oct. 19, 2016

Responses from an article on benchmarking that ran in Hotmail nearly a year ago continue to appear in my inbox. This new field evaluation and test method is being included in progressive service and maintenance agreements throughout the industry. It is proving as beneficial to customers as it is for service companies. Let’s take a look at what we’ve learned about the practice of benchmarking this past year and where it may be headed in the future.

Benchmarking Overview

Benchmarking is a five-minute field evaluation and test method included in a new breed of service agreements. Key system performance measurements are taken and recorded on each visit and then compared to the same measurements taken when the system was installed or optimized. 

Air pressure, temperature, and fan speed measurements are gathered under the same set of conditions and test points as when the system was optimized. Optimized means bringing the HVAC system to its best performance level.

Comparing the two sets of readings allows a technician to notice any deterioration in system performance. Any performance reduction can then be communicated to the customer and be repaired.

This testing is far beyond of the normal 15-point checklist included in the typical maintenance checklist that does little more than assure the equipment is still working. This information points to the performance level or score representing what the system’s operating efficiency. This is a big step up.

For more information on the basics of service benchmarking, follow this link: http://ncilink.com/RFBenchmark.This article compares service benchmarking to taking medical vital signs and describes how take and record system benchmark measurements.

How Techs Describe Benchmarking

Reports from the field describe adding benchmarking to your maintenance and service agreements like going from analog to digital test instruments. You can see beyond the basic tests and can pinpoint changes in the performance of the system that would otherwise go undetected.

Some techs say it is like following a paper map to get to your next service call compared to using the GPS in your phone and having audible instructions tell you the directions. Remember driving with a paper map draped over your steering wheel?

The primary benefit of benchmarking enables technicians to see beyond whether equipment is “still working” to how efficient the system is performing.

One technician said traditional service can be compared to driving a truck down the road without knowing where you are or how fast you’re going. Adding benchmarking testing and diagnostics to a service agreement is like adding a speedometer to know how fast you’re going and a navigation system so you can know where you are.

Multiplied Diagnostic Ability - What’s next?

I visited with my health care provider yesterday to get a prescription for an irritating problem that hasn’t gone away for a few days. After taking my vitals and a 30-second inspection, he diagnosed my issue and emailed a prescription to my pharmacy.

Then he said, “Rob, it’s good to see you, but why didn’t you just Facetime me? I could have saved you the trip?” What a huge change in the medical profession! He explained that in the past he could see maybe 25 patients a day. By offering digital visits, he envisions a day when he can “see” and help 90 patients a day. Could something like this apply to our industry?

With the shortage of skilled workers bearing down on the HVAC industry, progressive thinkers are looking into the future and discovering how to make the most of the available manpower.

What if a technician could arrive at a job site, scan the equipment label, and pull up the digital benchmark record of the system?

His handheld unit downloads a data file including the monitored results of a half-dozen performance measurements from the system. The software analyzes the trends of the system’s performance. On his screen appears an analysis of:

  • Any changes in the static pressure profile of the system. This detects a change in fan airflow, damage to the air distribution system, any variation in the minimum outside air setting, as well as new restrictions in the airside of the system. It can also uncover air filter restrictions or a dirty coil or fan motor decline.
  • The software analyzes the temperature monitoring data collected at specified benchmarking points. The data pinpoints and diagnoses a change in the system’s refrigerant circuit compared to its performance at the time of commissioning. The diagnostics identify any worsening in the combustion performance, reduced capacity in the system, or changes in duct leakage.
  • This same information can also signal failure or impending decline in the operation of system controls or other system components by combining pressure, airflow, temperature, and system Btu data. Since sensors would be constantly gathering, recording, and analyzing the data, why not add power, gas, and refrigerant sensors to analyze run time compared to outdoor temperature to tell us more?  

Software analysis using benchmarking performance data can combine the wisdom of system performance experts and present solutions neatly in an easy-to-understand format. This allows a single moderately-trained technician to out-produce a half dozen of today’s service technicians.

Predictive Maintenance

Each defect discovered through benchmarking is evidence of deterioration in system performance that can be corrected.   

The technician reviews the recommended diagnostics from the software, confirms or improves the prescription for needed system upgrades, then prices the repair.

Using the commissioning and performance monitoring data, the software analyzes deteriorated performance repair costs to the customer over the next 36 months. Since the payback of the repair is within the agreed cost parameters of the maintenance agreement, based on payback, the repair is preapproved. The service tech makes the repairs or forwards the work order to the system renovation crew for completion.

What Does Maintenance Maintain?

Data derived from benchmarking data documents that traditional maintenance tasks have little impact on installed performance of an unimproved system. Initial data shows that while service can occasionally uncover massive performance flaws, it is often focused on little more than keeping the equipment running and results in less than a 2% improvement in the operating performance.

From this we learn that without first making changes in the system necessary to maximize its installed performance score, maintenance lacks a worthy objective. Without considering the scored system performance, there is no understanding of what maintenance is for. There is more to service than to keep equipment running.

Benchmarking gives maintenance a purpose beyond keeping the equipment from being replaced. When coupled with optimizing system performance, it focuses on maintaining the score of a system. This becomes the target of maintenance. Without a target, maintenance has nothing to aim at.

Rob “Doc” Falke serves the industry as president of National Comfort Institute, an HVAC-based training company and membership organization. If you're an HVAC contractor or technician interested in a sample benchmarking label and test procedure contact Doc at [email protected] or call him at 800-633-7058. Go to NCI’s website at nationalcomfortinstitute.com for free information, articles, and downloads.

About the Author

Rob 'Doc' Falke | President

Rob “Doc” Falke serves the industry as president of National Comfort Institute an HVAC-based training company and membership organization. If you're an HVAC contractor or technician  interested in a building pressure measurement procedure, contact Doc at [email protected]  or call him at 800-633-7058. Go to NCI’s website at NationalComfortInstitute.com for free information, articles and downloads.