Hidden HVAC Energy Costs: The Blind Spot Burning Cash in Commercial Buildings

Commercial buildings are under increasing pressure to reduce operating costs, improve energy performance, and meet tightening decarbonisation expectations.

Yet across Australia, one of the largest and least‑understood costs is hiding in plain sight: HVAC systems that appear to be “off,” correctly scheduled, or optimised but continue running, cycling, or working against themselves in the background.

This silent behaviour burns electricity, inflates emissions, and drains budgets and in most buildings, no one even knows it’s happening.

What Your Energy Bill Doesn’t Tell You

Energy bills show kilowatt‑hours and dollars, but they don’t show the story behind them. They won’t tell you:

• That a rooftop unit is quietly ramping compressors at midnight.

• That a heat pump is reheating air it just cooled because a stale sensor pushed it into a default protection mode.

• That fans are running long after the building has closed because the controller is attempting to stabilise supply‑air temperature.

• That two pieces of equipment are fighting each other one heating, one cooling while still technically meeting set-points.

To the operator, scheduling looks correct. The system shows “off.” The controller reports everything within limits. Yet the load profile refuses to drop.

And here’s the catch: HVAC systems are built with protective logic designed to maintain supply-air stability, but that same logic often overrides controller's commands without operators ever knowing.

Even when the system is programmed to be “off,” the onboard logic can force compressors on, select cooling/heating, or fans to continue running to satisfy internal rules. This behaviour is invisible from the front‑end interface.

Your Energy Bill is a summary, not a Diagnostic

Through our first-hand observations of installations across a diversity of customer sites including colleges, bulk retail outlets, universities, restaurants, and data facilities a consistent pattern has been revealed, everything appears normal from the operator’s perspective.

Programmed "schedules" show systems turning off, dashboards report stable conditions, and climate control performs as expected. No alarms are raised, no faults appear, and nothing suggests a problem.

But the energy bill was only a summary, not a diagnostic tool. Behind that summary, the systems are often running far more than anyone realises, silently driving up energy use and operational cost.

The fact is the equipment owners weren’t looking in the wrong place or ignoring these inefficiencies, they simply had no tools to see what the equipment was actually doing.

The behaviour was invisible, and the energy bill only hinted that something was off without revealing the cause.

The Data Told the Whole Story

Once real-time, equipment-level data is captured, the truth becomes impossible to ignore. Patterns emerge instantly:

• Compressors cycling outside scheduled hours

• Evaporator fans running 24 hours a day

• Units oscillating between heating and cooling

• Supply air hitting set point only because equipment is overworking and not operating efficiently

This is the reality hidden behind "normal" operation. HVAC control logic is designed to preserve temperature at all costs even if that means defeating the programmed schedule, fighting other components, or consuming far more energy than intended.

In building after building, the gap between what the system is meant to do and what it's actually doing becomes stark.

Equipment Age Isn't the Major Problem

The assumption is often that energy waste comes from “old units.” But in truth, the problem is largely behavioural, not mechanical.

Modern systems with advanced logic can waste just as much as older ones. In fact, the more complex the controller as in newer equipment, the more pathways exist for unintended runtime issues to occur.

The issue isn’t the hardware it’s the lack of visibility into how that hardware behaves minute-to-minute. Buildings with brand‑new assets frequently show the same runaway patterns seen in buildings with 20‑year‑old equipment.

HVAC equipment Age isn’t the culprit. Lack of insight is.

It’s Not an Industry‑Specific Problem

This hidden HVAC waste is universal. It also appears in:

• Retail

• Education

• Healthcare

• Corporate offices

• Government buildings

• Industrial facilities

• Hospitality

• Aged care

• Data‑heavy environments

Whether the building is a courthouse, a university, a fast‑food outlet, or a shopping centre, the same pattern repeats: systems that appear off are often quietly operating in the background.

No sector is exempt, because every sector relies on HVAC equipment governed by the same logic, assumptions and blind spots.

Why Waste Goes Unnoticed

Most buildings operate on trust‑based assumptions:

• The system is scheduled, so it must be off.

• The thermostat is satisfied, so energy use must be low.

• The controller says “OK,” so performance must be fine.

But HVAC systems follow internal logic trees that prioritise equipment protection, coil temperature, frost prevention, and supply‑air stability. This logic can:

• Override schedules

• Ignore commands

• Run fans for anti‑short‑cycle protection

• Revert to factory default settings

• Heat and cool simultaneously

• Maintain comfort even through wildly inefficient operation

Because the building still feels comfortable and no alarms are triggered, the waste continues undetected. 

The only signal is a higher‑than‑expected energy bill and even that is too abstract to pinpoint the cause.

How Much Is Being Wasted

Across commercial buildings, the waste is significant. Studies and on‑site trials consistently show:

• 10-40% percent unnecessary HVAC energy consumption

• Thousands of annual run‑hours that shouldn’t exist

• Tens of thousands of dollars per building in avoidable costs

• Large Scope 1 and 2 emissions increases from unnecessary compressor and fan use

Scope 1 refers to direct emissions from fuel burned on‑site, such as gas used for heating. Scope 2 refers to indirect emissions from the electricity your building purchases. When

HVAC equipment runs unnecessarily, both scopes rise even though the building appears to be operating normally.

Across multi‑site portfolios, the numbers grow exponentially. A business with 50-100 sites can unknowingly waste hundreds of thousands of dollars per year.

And this waste isn’t hypothetical it’s happening right now, silently, across thousands of buildings.

Why This Blind Spot Matters Now

With electricity prices rising, pressure from NABERS* and BEED* increasing, and net‑zero requirements accelerating, unplanned HVAC runtime is no longer a minor inefficiency it’s a material financial and compliance risk.

*NABERS is Australia’s national energy rating system for buildings, and;

*BEED is the new mandatory Building Energy Efficiency Disclosure framework driving deeper reporting and accountability)

What once blended into background noise is now a meaningful line on the P&L.

• Buildings that can’t see inside their HVAC logic can’t control it.

• Buildings that can’t control it can’t reduce it.

• Buildings that can’t reduce it won’t meet the energy and emissions targets of the next decade.

How We Can Help

Cresstec’s HDAC and REED systems were built for this exact blind spot.

• HDAC actively corrects runaway control logic, stabilises operation, and reduces unnecessary compressor and fan cycles without affecting comfort.

• REED while providing the benefits and functionality of HDAC also monitors refrigerant conditions and detects inefficiencies and micro‑leaks that push systems into high‑energy behaviour.

Together, they allow HVAC systems to run as intended not just as programmed delivering immediate energy savings and meaningful emissions reductions.

Digital Smart Power Meters on Each Compressor and the Overall System

The foundation of solving the problem is measurement.

Most buildings rely on a single main electricity meter or broad sub‑metering, which only shows total consumption. It cannot tell you which unit is running, why it is running, or whether the behaviour matches the intended schedule.

Digital, high‑resolution power meters change that completely. By measuring each compressor, fan and system feed individually, they reveal:

• Exactly when equipment is running

• How hard each component is working

• Which units are wasting energy or cycling unnecessarily

• Where scheduling is being overridden by internal logic

• The true cost of every unexpected hour of runtime

This level of detail finally shows the difference between "what the controller says" and "what the equipment is actually doing".

It gives operators visibility they have never had before and provides the evidence needed to correct behaviour, verify improvements, and maintain efficiency over time.

This is the data buildings have been missing for decades and it exposes inefficiencies in minutes, not months.

Letting the Numbers Talk for Themselves

Once the data is live, there’s no need for guesswork or theoretical models. 

The numbers tell the story clearly:

• Unintended runtime becomes visible.

• Wasted kilowatt-hours are quantified.

• Savings delivered by HDAC and REED can be measured and verified

• Operational behaviour becomes transparent, not hidden behind system logic

It transforms HVAC from a black box into a predictable, optimisable asset.

Take Control: Expose and Eliminate Your Hidden HVAC Energy Costs

Every day that hidden HVAC runtime continues, your building is quietly losing money and energy. The fastest path to savings is visibility.

Contact us for a site assessment, Let us identify inefficiencies, reveal hidden behaviour, and demonstrate measurable savings. Once the numbers are clear, action becomes simple, repeatable, and scalable across your entire portfolio.

Stop paying for energy you never intended to use. Organise your site assessment today and put your hidden HVAC bill to the test.

References

• ASHRAE Guideline 36-2021 : High-Performance Sequences of Operation for HVAC Systems. Fail-safe behaviours that can cause equipment to run to maintain conditions

• CSIRO & DISR (Department of Industry, Science and Resources) : Part of a series of reports on HVAC energy efficiency in Australian buildings. Highlights prevalence of factory-set logic and poor commissioning as key sources of energy waste.

• Energy Efficiency Council (EEC), Australia : “HVAC Optimisation” series. Emphasises the role of onboard logic in unintended runtime and notes the importance of real-time monitoring to combat hidden energy use.

• NABERS Technical Documentation : NABERS Energy for Offices and Shopping Centres. Describes challenges in attributing energy use to specific systems without sub-metering, and how HVAC often accounts for 40–60% of total site usage.

• BEED (Building Energy Efficiency Disclosure) Consultation Paper : Reinforces the importance of equipment-level data in meeting regulatory and reporting requirements, especially for buildings over 1,000 m².