AHR Expo 2026 Session Recap | AutomatedBuildings.com
Heat pump technology works. That much is not in dispute. What is in dispute, and what a packed room at AHR Expo 2026 made clear, is whether the industry surrounding that technology is ready to deploy it reliably at scale. The answer, for now, is: not consistently. But the problems are known, the solutions are largely understood, and the gap between knowing and doing is closable.
This session, hosted by AutomatedBuildings.com, brought together a consulting engineer and a panel of application and sales engineers with decades of combined experience in hydronic systems, modular equipment, and central plant design. What followed was one of the more candid and practically useful conversations of the conference. Here is what came out of it.
The Core Problem: We Are Pushing Machines Past Their Sweet Spot
The industry spent 80 years perfecting chillers and boilers. Heat pumps have been in serious commercial deployment for a fraction of that time, and the mistakes being made today are often the same ones made with earlier technologies, except we do not yet have 80 years of learned instinct to catch them early.
The most consistent failure pattern is running equipment at the edges of its operating envelope: chasing the highest possible leaving water temperatures, the lowest possible flow rates, the largest possible delta T, all at the same time. A machine can technically hit those numbers. The question is whether it can do so reliably and consistently over years of operation. Usually, the answer is no.
The fix is straightforward in principle: understand the equipment’s true sweet spot and design the system around that, not around maximum nameplate performance. Pushing for 135 degrees, only to find on startup day that the machine tops out reliably at 125, is an avoidable problem. It requires earlier, deeper engagement between the consulting engineer, the manufacturer’s application team, and the equipment representative, not at startup, but at design.
Do Not Operate a Heat Pump Like a Boiler
This sounds obvious. In practice, it is not.
Control systems are regularly set up to disable a heat pump once it reaches the set point, wait for the temperature to drift, and then restart the machine from a cold state. That is how you might sequence an atmospheric boiler. It is exactly the wrong approach for a heat pump.
The correct approach is simpler: enable the machine, set a point, set the appropriate flow rate, and let its internal controls do the rest. The unit controller was designed to manage staging, capacity modulation, and set point maintenance. Overriding that logic with external BAS sequences that second-guess the machine creates alarms, reduces reliability, and gives the appearance of a broken system when the controls are the actual problem.
A related issue is the blind application of ASHRAE Guideline 36 sequences to heat pump plants. Those guidelines were written primarily with chiller and boiler plants in mind. Applying demand-based staging logic that forces a heat pump to cycle off every 15 minutes ignores how the equipment’s internal logic actually works. The people writing those guidelines have, in many cases, never sat down with a manufacturer’s application engineers to understand the consequences. That conversation needs to happen at the standards level, not just on individual job sites.
Startup Is Not Commissioning
This distinction matters more with heat pumps than with almost any other HVAC equipment type.
A startup means a technician has verified wiring, loaded the program, set initial parameters, and confirmed the machine will run. Commissioning means the system has been run through its full range of operating conditions, observed, adjusted, and verified to perform correctly. With a boiler, the gap between those two things is relatively small. With an air source heat pump, the gap is seasonal.
Air source heat pump performance varies significantly with outdoor conditions. A system commissioned in October has not been commissioned for a Denver winter. A system commissioned in April has not seen peak cooling demand. Seasonal commissioning is not a luxury on these projects. It is a requirement for understanding how the system actually behaves.
There is also a distinction worth drawing between commissioning for reliability and commissioning for optimization. Both matter, but they are not the same exercise. A system that squeezes every last unit of efficiency under ideal conditions but faults unpredictably under real-world load variation is not a good outcome. The priority sequence should always be: get it working first, then get it working efficiently.
Budget is the consistent obstacle here. Commissioning costs money. Contracts close, GCs move on, and the careful seasonal follow-up that these systems need often does not happen because nobody allocated funds for it. If you cannot budget for proper commissioning, the honest answer is that you cannot afford the heat pump.
Retrofits Are Hard. Say So Up Front.
New construction allows the mechanical design to inform the building. Retrofits do not. Pipe sizes are fixed. Duct layouts are fixed. Terminal units were sized for high-temperature hot water. The owner has a budget number in their head based on what they paid for the last boiler replacement.
None of those conditions is friendly to heat pump retrofits, and yet a significant share of the industry’s current decarbonization work is exactly this: replacing steam or high-temperature hot water systems in buildings that were never designed for low-temperature heat delivery.
The work can be done. There are successful examples. But the projects that go wrong almost always share a common failure: the difficulty was not communicated clearly enough, early enough. Owners are being told they must decarbonize without being told what that actually requires. Consultants are handed mandates without road maps. The result is sticker shock at the budget stage, compressed timelines, skipped commissioning, and buildings that technically have a heat pump installed but are running on the backup boiler three years later.
The advice that emerged from this session is consistent: pick the team early, get everyone at the table before design begins, and have the hard conversation about cost, complexity, and timeline before anyone draws a single pipe. Design-bid-build procurement is particularly poorly suited to these projects. The early involvement of contractors and manufacturers in the design process is not a luxury; it is one of the most effective cost control mechanisms available.
The Information Gap Is Real, and the Industry Is Responsible for It
One of the more candid exchanges in the session revolved around a simple complaint: consulting engineers often cannot get the technical information they need to design these systems well. They cannot find out how a specific machine stages its compressors. They cannot learn what happens to internal logic when an external BAS sends a shutdown signal at the set point. They cannot determine the actual minimum flow requirement for a package unit versus a modular unit.
The reason is not malice. The reason is pace. Manufacturers are replacing entire refrigerant lineups and launching new product families faster than their application documentation can keep up. The sales rep is often the only point of contact, and they frequently do not have the answers. The application engineers who do have the answers are buried.
The solutions being applied in better-run organizations include factory visits, direct relationships with application engineering teams, and the development of internal application guides based on those conversations, which then get shared with design engineers at lunch-and-learns before the project starts. That model works. The problem is that it requires time and initiative that not every firm or rep can provide on every job.
What the industry needs is better baseline documentation from manufacturers, released alongside products rather than months after. What individual practitioners can do right now is be direct: ask the rep for access to the manufacturer’s application team, not the sales sheet. Most reps who are doing their jobs well will make that connection.
The Bottom Line
Heat pump projects fail for mostly preventable reasons. The equipment works. The physics works. What fails is the system around the equipment: hydronic design that ignores minimum flow requirements, control sequences that treat a heat pump like a boiler, commissioning scopes that end at startup, and project structures that leave the hard conversations about cost and complexity until it is too late to have them.
The consistent thread from every experienced voice in this session was: get everyone involved early, keep the system as simple as the load will allow, let the machine do what it was designed to do, and build in time and budget for commissioning across all seasons. None of that is new advice. The industry just needs to follow it.
SPEAKERS
Brad White, President, SES Consulting
Brad is President of SES Consulting and a Professional Engineer with over 15 years of experience in energy efficiency, low carbon technologies, and smart building systems. He has demonstrated his passion for the sustainable use of energy throughout his professional career and this continues to be a driving force in his work. Brad works closely with clients to integrate leading edge technologies and energy conservation strategies into existing buildings; these can include fault detection and analytics, electrification of heating systems, and advanced controls. Brad is a Contributing Editor to AutomatedBuildings.com and a member of the City of Vancouver’s Technical Advisory Committee on Existing Multi-Unit Residential and Commercial Buildings.
Dan Gentry, Application Engineer, Trane
Dan Gentry is an Applications Engineer at Trane in La Crosse, WI. He joined Trane in 2018 after 8 years at another local WI based chiller manufacturer. Dan first interned at Trane in the Technology Lab where he worked in the acoustic lab while attending school through 2008. His areas of expertise revolve around chiller plants, heat recovery and heat pump systems, data center chiller plants and their reliable and efficient design and operation. He graduated from Ferris State University in 2011 with a bachelor’s degree in HVAC Engineering Technology. Dan enjoys spending time with his family on the Mississippi river and relaxing time at the family cabin in the UP.
James Murphy, Sales Manager, LONG Building Technologies
James Murphy is a dedicated and accomplished Sales Manager at LONG with 25 years of experience in the industry. Specializing in large commercial and industrial equipment, James has primarily focused on working with consulting engineers. With a degree in Mechanical Engineering from Vanderbilt University, James brings a strong technical background to the sales team. Throughout his career, James has consistently demonstrated exceptional leadership and strategic thinking, achieving numerous milestones and driving significant results. Outside of work, James enjoys spending time with his wife and four children, exploring the mountains and soccer fields of Colorado.
Matthew Smith, Product Specialist, Air Treatment Corporation
Matthew Smith is a senior HVAC technical specialist with more than 20 years of hands-on experience in hydronic systems, modular equipment, and central plant applications. He is currently a Product Specialist at Air Treatment Corporation, supporting high-performance HVAC solutions including modular chillers and heat pumps, hydronic system integration, and advanced control strategies.
Matthew’s background includes field service, factory support, system startup, and design review, with deep experience in modular chiller and heat pump applications. His expertise covers staging and load-sharing logic, pumping and decoupling strategies, and resolving real-world operational challenges. He works closely with engineers, contractors, and owners to develop effective Sequences of Operation, troubleshoot complex hydronic issues, and optimize system performance.
Prior to joining Air Treatment Corporation, Matthew held senior technical roles at Multistack and Trane, where he supported factory startups, led installation and commissioning training, and serviced large-scale chilled water and heat pump systems. His experience spans ammonia and process cooling, traditional comfort HVAC, and modern electrification-focused designs.
Matthew regularly delivers engineering lunch-and-learns and technical training sessions, translating manufacturer application guidance into practical, field-proven solutions. His focus is helping design teams and operators successfully implement modular heat pump and hydronic systems that improve efficiency, resiliency, and long-term performance.
