Self-diagnostics are proving to be a huge component of the growing role of the Internet of Things (IoT) in the HVACR industry.

They’re heralded for their ability to save contractors precious time and money and for their ability to communicate a problem before a homeowner even realizes there is one. So, what are self-diagnostics and what does the future hold for this technology?

“Self-diagnostics describe the collection of hundreds of data points, such as power usage, entering or leaving temperatures, outdoor air temperature, humidity, set points, runtime, etc., from a piece of HVAC equipment,” said John Marden, Intelligent Solutions service program manager, Daikin Applied. “Self-diagnostic algorithms analyze combinations of data in both real-time and trends over time and look for anomalies. Similar to monitoring cholesterol levels or blood pressure in the human body, there are some key real-time metrics that are excellent indicators of HVAC equipment health.  

“In addition, storing data points on equipment and analyzing trends over time allows for deeper diagnostics into changes from a healthy baseline — similar to a human concussion protocol,” he continued. “Self-diagnostics will help technicians maintain the efficiency of HVAC equipment, improve uptime, and allow equipment to have a longer effective life by identifying small maintenance issues and fixing them before they become bigger problems.”


Manufacturers are honing in on creating products that are able to communicate with the technician in real-time and self-diagnostics allows them to do so. As this technology continues to evolve, is it something that is more so for residential buildings, commercial, or both?

“Self-diagnostics are prevalent in both commercial and residential applications,” said Gary Hsieh, director of product and business development, Lux Products Corp. “Commercial applications/products tend to focus more on having an informed building manager, and there are typically defined levels of understanding of labor cost, restrictions of maintenance hours, etc. In these situations, self-diagnostics can be effective tools. In residential applications, self-diagnostics helps the DIY installation flow and aids in preventive maintenance, which typically benefits users. The challenge, though, is understanding the methodologies behind the self-diagnostics. Without this, they are not effective troubleshooting tools for contractors.”

Self-diagnostics are more commercial at this point, but residential is coming on fast, said Joe Summers, product planner, refrigeration, commercial and residential solutions platform, Emerson.

“Businesses look at the total cost of ownership and are adopting at a faster rate. Residential features, such as thermostats with a simple timer that can alert users to change an air filter, can give heating and a/c equipment a longer life and help it perform more efficiently. We offer a service to monitor an entire house’s HVAC system. Our call center can monitor the system and call a technician to fix an issue before it becomes an expensive problem.”

Currently, the primary challenges with self-diagnostics are assessing the large amount of data and to correctly assess that data.

“The sheer volume of data we can collect and store on each piece of equipment can be daunting,” said Marden. “The biggest challenge is to track, report, and alarm on meaningful trends and events that can make equipment last longer and run more efficiently while avoiding nuisance alarms.”

“The primary challenge when it comes to self-diagnostics is how meaningful the responses are,” said Hsieh. “Contractors need to feel confident that the output provided is driving the best action and is not just a bunch of information without a recommended corrective action. The information must also be presented in a clear and simple manner so that action can be quickly and easily taken without assumptions. And, finally, the self-diagnostics need to be robust enough to help a contractor make the best on-site decisions.”

There’s been talk that some feel self-diagnostics are “dumbing down” the industry; however, many manufacturers don’t see that occurring.

“Not at all,” said Rick Wilson, director of sales and marketing, Arzel Zoning Technology Inc. “I would not call it dumbing down, but maybe plug and play. Over the years, equipment has become more modular, which has allowed for the replacement of entire PC boards or complete subassemblies to be replaced rather than individual components.”

“Self-diagnostics helps skilled technicians work smarter, not harder, without spending empty hours on, say, truck rolls that weren’t necessary,” said Marden. “Factory recommended commissioning/recommissioning procedures, maintenance schedules, diagnostics, set points, etc. are all built into Daikin’s Intelligent Equipment and are unique for each serial number. All these data points are available to technicians on their smartphones, tablets, or computers. Any changes are stored and available for the entire life span of the equipment. This allows technicians to review any work or changes done to the equipment and bring it back to factory-recommended specifications without having to spend time looking up the specs for each unique piece of equipment.”

Self-diagnostics are making it easier to keep constant tabs on HVAC systems, making sure they’re always running efficiently and saving the end user money, said David Hules, director of marketing, commercial air conditioning, commercial and residential solutions platform, Emerson.

“With the shortage of technicians and the increasing complexity of systems, self-diagnostics are enabling technicians to be more effective in their work,” he said.


The future of HVAC systems largely lies in self-diagnostics. Manufacturers are looking to transform most or all of their products to be able to communicate with technicians and homeowners.

“Daikin is targeting more and more pieces of equipment for both factory-built and retrofit intelligent equipment diagnostic packages,” said Marden. “There will always be a low end of the market, but with the cost of sensors dropping, self-diagnostics may become an expectation or requirement to compete. Daikin sees a big growth opportunity with Intelligent Solutions that include self-diagnostics.”

“Most units do [utilize self-diagnostics] today already,” said Summers. “Those that don’t are usually legacy-type products that are on their way out. The newer products with the self-diagnostic ability are more efficient and have better reliability.”

“It’s inevitable that all units will eventually feature self-diagnostics,” said Udi Meirav, CEO, enVerid Systems.

Wilson said Arzel Zoning will continue utilizing these technologies to advance its products’ reliability and make them easier for contractors to repair.

Self-diagnostics are known to be correlated with condensing units, but the future of this technology will likely expand into other areas.

According to Marden, Daikin Applied is looking to include self-diagnostics in all aspects of its HVAC systems

“Self-diagnostics could apply to any part of the HVAC system that could fail or requires maintenance,” he said. “For example, analyzing power use on each particular piece of HVAC equipment allows self-diagnosis regarding any unexpected change in power consumption. This could mean that a fan is failing or incoming air is blocked. If the unit is maintaining output temperature, the technician may choose to wait a while before making a service call. If the output temperature is dropping, the technician may make an emergency service call. This sort of analysis of the entire piece of equipment allows maintenance technicians to be more efficient and proactive.

“Technicians can base service visits on events, rather than the calendar,” Marden continued. “Adding additional sensors could also help improve self-diagnostics, particularly in cases like clean room manufacturing or museum collections where the customer requires constant HVAC uptime to effectively run their business.”


With self-diagnostics, different manufacturers will have different types of systems. Therefore, technicians will need to be trained in order to be properly educated on self-diagnostics systems.

“Just as they need to learn about new digital and communicating diagnostic tools, they also need to learn new troubleshooting and repair techniques,” said Wilson. “Look in the tool box of the advanced tech, and you might find the usual nut drives and snips, but you will also find many new tools that weren’t available just a few years ago that are digital and communicate to a mobile device.”

Daikin Applied’s self-diagnostic technology is built to be user-friendly, so both tech-savvy technicians and those less ‘techy’ can navigate the system, Marden said.

“Technician skill sets all differ from one another,” he said. “It’s similar to the transition auto mechanics made as cars gained more electronic parts and on-board computers. Today’s technicians will expand their skill sets to become controls and software pros and trusted advisors for entire building systems. Training programs could morph to graduate prepared technicians; but the onus is not all on the technician or the school. The user experience on self-diagnostic interfaces should be intuitive so that skilled technicians or less experienced building staff can easily benefit. That’s our goal with Intelligent Solutions.”

Self-diagnostics are changing the way technicians are being educated, said Meirav.

“I have no doubt it will [change things],” he said. “You see this in other industries. Conditions need to become more sophisticated. Generally, the whole aspect of self-diagnostics is becoming bigger, and, with that, the way we train is going to go in the same direction.”

Publication date: 7/31/2017

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