How to Improve Boiler Efficiency: A Plant Operator’s Guide

Rising gas bills show up fast in a boiler house.

The load has not changed much. Production still needs steam. The header still needs pressure. Yet the fuel meter keeps climbing.

Boiler efficiency is the share of fuel energy delivered to the plant as useful steam or hot water. A well-maintained industrial boiler on natural gas reaches 80% to 85%. Most Australian plants achieve only 70% to 75% in service, and the gap between the two figures is roughly one dollar in every eight on the gas bill. Almost all of the gap is recoverable without touching production.

How to improve boiler efficiency is rarely a question with one big answer. In practice it runs as eight steps in cost order. First measure the baseline and rank the losses. Then tune combustion, recover waste heat, control blowdown, protect the waterside and match the boiler to the load. Finally, retest and verify the saving.

O’Brien Energy is Australia’s largest privately owned boiler company, with more than 350 years of combined team experience, 40,000-plus jobs completed and 24/7 nationwide breakdown response. This guide is written for real plants. Steam users, hot water users, and process sites chasing lower gas use without putting throughput at risk.

For upgrades, service or new plant selection, see our range of industrial boilers, engineering and consulting, and boiler maintenance services.

What boiler efficiency means

Boiler efficiency is the useful heat output delivered to the plant divided by the energy input from the fuel, expressed as a percentage. In practical terms, boiler efficiency is how much of the gas, oil or biomass purchased leaves the boiler as usable steam or hot water. A well-maintained industrial boiler runs 80% to 85%. Poor combustion, fouling, heavy blowdown, short cycling and cold feedwater pull the same boiler into the low 70s.

The target is simple. More useful heat, less wasted heat, for the same output. Driving the boiler harder is not the same thing.

Fuel is the dominant lifecycle cost of an industrial boiler, usually several times the purchase price across 20 years of service. For example, a two-point efficiency gain on a plant burning $400,000 of natural gas a year returns about $9,500 annually, every year, with no change to production output. Better efficiency also brings lower carbon emissions, more stable header pressure, reduced burner stress, longer asset life and more predictable maintenance planning.

The boiler room is one energy conversion system: burner, furnace, heat transfer surfaces, feedwater, blowdown, controls, flue, economiser, condensate return, water treatment and operator rounds. Efficiency sits across all eleven, which is why single-component upgrades so often disappoint.

How to calculate boiler efficiency

A boiler efficiency calculation is the ratio of useful heat output to fuel energy input, expressed as a percentage, and two accepted methods produce the figure.

The direct method divides useful heat output by fuel energy input and multiplies by 100. For example, 8,000 kW of useful steam output against 9,500 kW of fuel input gives 84.2%. The direct method tells an operator where the plant stands, and needs accurate steam and fuel metering to mean anything.

The indirect method starts at 100% of fuel input and subtracts each measured loss: stack loss, moisture, carbon monoxide, unburnt fuel, blowdown, radiation and cycling. A direct test may report 82%, but only the indirect breakdown shows whether the missing 18% is excess air, a fouled tube bank, an over-open blowdown valve, or a burner cycling forty times an hour.

Run both on the same test. Agreement within two or three points confirms the instrumentation. A wider gap points at a metering fault before a boiler fault, and chasing the boiler before fixing the meter wastes a shutdown.

The boiler efficiency formula, and the two numbers that break it

The boiler efficiency formula for the direct method is:

Boiler efficiency (%) = useful heat output ÷ fuel energy input × 100

For a steam boiler, useful heat output is steam mass flow multiplied by the enthalpy rise between feedwater and steam. Fuel energy input is fuel flow multiplied by calorific value. A real test needs eight reliable inputs: steam flow, steam pressure, steam temperature where superheated, feedwater temperature, fuel flow, fuel calorific value, the operating period, and blowdown conditions where included.

Two details decide whether the result means anything. First, state the calorific value basis, because gross (higher heating value) and net (lower heating value) differ by roughly 10% on natural gas, which is larger than most efficiency improvements being measured. Two plants quoting 85% on different bases are not running the same boiler.

Second, state the measurement boundary: boiler only, boiler plus economiser, boiler house, or complete steam system. A stated boundary prevents most of the arguments that follow an efficiency test.

Standards and repeatability

In Australia, AS 2593 governs boiler operation and attendance discipline, and O’Brien Energy supplies and maintains AS 2593-compliant systems. Efficiency testing should also follow site regulations, manufacturer documentation and statutory inspection requirements.

Repeatability is the part operators most often get wrong. Same instruments, same load condition, same fuel basis, same boundary, same calculation method. Change any one of the five variables between tests and the numbers drift far enough to hide a real 3% gain, or to invent a gain that never existed. In practice, a test at 60% load reads several points away from the same boiler at 90% load, so log the conditions alongside every result.

Where the losses are, in rank order

Boiler heat loss is the sum of eight predictable paths, and the paths are not equal in size. On a boiler running at 82%, the missing 18% left through these eight, and flue gas is normally the largest single share.

1. Stack and flue gas, usually the largest. Hot gases carry energy straight out of the building, and both excess air and fouling make the loss worse.
2. Excess air. Every percentage point of unnecessary combustion air is fuel spent heating atmosphere.
3. Blowdown. Hot treated water discharged from the boiler carries heat, chemicals and water treatment cost with it.
4. Fouling. Soot on the fireside and scale on the waterside both insulate the tubes.
5. Radiation and convection. Casing, valves, flanges and uninsulated fittings, continuously, for as long as the boiler stays hot.
6. Cycling. Each purge and light-off pushes air through the boiler and heat out the flue.
7. Steam and condensate losses. Leaks, failed traps, vented flash steam, open condensate drains.
8. Control losses. Wrong setpoints, drifting sensors, poor sequencing.

Biggest first. Safest first. Measurable first. In practice that order protects capital better than any brochure, because the cheapest losses are usually the largest.

Combustion efficiency and excess air

Combustion efficiency measures how completely the burner converts fuel into heat. Combustion is the fastest and cheapest way to reduce boiler fuel costs, and also the setting that drifts most.

Perfect combustion on natural gas needs a fuel-to-air ratio of 9.7:1, with all oxygen consumed and all fuel burned. No plant runs at the theoretical ratio. For safety and maintenance margin, an industrial burner is typically commissioned with a minimum of 24% to 30% excess air. Below the 24% floor, combustion produces unburnt fuel and carbon monoxide, which is both toxic and explosive. Above 30%, gas is being burned to heat air that leaves through the stack.

So the goal is not the lowest possible oxygen reading. The goal is stable, complete combustion at the lowest safe excess air, held across the whole firing range.

The firing range is where most plants lose money. A burner with simple controls has the combustion air fan set for high fire. If the fan cannot vary speed, it still delivers full high-fire air volume when the burner modulates down, so excess air climbs far above the 24% to 30% band and efficiency falls away as demand drops. The effect is worst at low fire, which on many sites is where the boiler spends most of its operating hours. The fix is combustion control hardware: a variable speed drive on the air fan plus O2 trim, which measures flue gas oxygen continuously and corrects the ratio in real time instead of holding a single commissioned curve.

Regular flue gas analysis makes all of this visible. Track oxygen, carbon monoxide, stack temperature, flame stability, burner and fuel pressure, damper and gas valve position, linkage condition and draft pressure.

Poor combustion leaves clues before the gas bill shows anything. Rumbling. Flame instability. Rising oxygen. Carbon monoxide spikes. Soot. Wide swings during modulation. The usual causes are a burner out of tune, worn linkages, damper slop, poor gas pressure control, incorrect draft, fouled heat transfer surfaces, a drifting oxygen sensor, or commissioning settings never corrected after maintenance. Boiler tuning needs calibrated instruments and licensed people. Guesswork on a gas train is not a saving.

Stack and flue-gas loss

Stack loss is the energy carried out of the boiler by hot flue gas, and on most industrial boilers it is the largest single loss. Stack temperature is therefore the most useful number an operator can trend. For example, on a boiler running at 82% efficiency, most of the missing 18% leaves through the flue.

Stack temperature responds to boiler design, load, cleanliness, firing rate, excess air, feedwater temperature and heat recovery equipment. With so many variables feeding one reading, a single measurement proves little and a trend at comparable load proves a great deal. A rising trend at constant load and constant excess air means heat transfer is degrading, and the cause is almost always soot on the fireside or scale on the waterside.

Scale is the expensive one. A thin, hard scale layer conducts heat far worse than steel, so the same fuel produces less steam and a hotter stack, and the tube metal runs hotter too. Scale is therefore a reliability problem as well as an efficiency problem, and scale starts in the feedwater.

Controlling stack loss means regular flue gas analysis, burner tuning, fireside cleaning, waterside inspection, scale prevention, economiser inspection, draft control, and O2 trim where appropriate. The stack is not just an exhaust. The stack is a loss meter, and most plants never read it.

Blowdown and feedwater

Boiler blowdown removes the dissolved and suspended solids that concentrate as water turns to steam and leaves impurities behind. Blowdown is a protection system, not a waste.

Too little blowdown risks carryover, foaming, scaling and corrosion. Too much wastes heat, treated water and chemicals. Efficient operation sits between the two failures, set by measured water chemistry and site limits rather than by habit.

Manual blowdown works on small or simple systems, but manual control drifts, because operators over-blow to buy safety margin. Automatic TDS control holds concentration at the actual limit instead of well below it. Continuous surface blowdown heat recovery goes further, holding target total dissolved solids while recovering heat from the high-temperature discharge into incoming cold makeup water. On steam plant, blowdown heat recovery typically pays back within a few months from fuel savings alone.

Feedwater temperature is the other major lever, and the more commonly neglected one. Cold feedwater has to be lifted further to reach boiling, and the lift is paid for in gas. Feedwater performance depends on condensate return rate, deaerator operation, feed tank temperature, makeup volume, flash steam recovery, economiser performance, line insulation, steam trap condition and water treatment quality.

Condensate return is the highest-value item on that list, because returned condensate brings back heat, treated water and chemical value at the same time. Every kilogram lost is replaced by cold makeup water, which must then be treated and heated from ambient. In practice, a site running 40% condensate return instead of 80% pays three times over: fuel, water and chemicals. So a boiler efficiency programme has to cover the steam and condensate system, not just the pressure vessel.

Insulation belongs in the same category. An un-insulated 4-inch (DN 100) globe valve in a 160°C system loses about 1,199 watts continuously, which is roughly 629 cubic metres of natural gas a year from one valve. Removable valve and steam trap jackets recover most of the loss and still allow access for maintenance. Count the bare valves and flanges in your boiler house, then multiply.

Economisers and heat recovery

An economiser is a heat exchanger fitted to the boiler stack, capturing waste heat from exhaust gases to preheat feedwater. Fitting an economiser can improve overall boiler efficiency by up to 10%, straight off the annual fuel bill. Typical fuel savings run 5% to 10%, and most installations recover their cost within one to three years.

An economiser is the most common industrial boiler efficiency upgrade on plant with long operating hours and steady loads, and the value depends entirely on the site: load profile, stack temperature, fuel cost, feedwater temperature, available space, controls, condensation risk, maintenance access and boiler design. Three configurations cover most industrial cases.

Single-stage feedwater economiser. Individually removable finned tubes, compression-fitted to the liquid manifold so tubes can be replaced without welding, and no pressure vessel welds inside the shell. An internal stainless steel gas bypass tempers the exit gas for stack corrosion control, or holds water temperature when more heat is available than the water can absorb. Suits steam and hot water applications at all boiler design pressures.

Condensing economiser. Preheats almost any cool liquid stream (makeup water, wash water, process water) below roughly 50°C, capturing considerably more heat because the unit condenses moisture out of the flue gas. Tube cores are 316 stainless steel with aluminium fins, with a 316 stainless gas bypass, interior shell and condensate drain, because the condensate is acidic. Condenses on natural gas only.

Blowdown heat recovery. Recovers heat from continuous surface blowdown into cold makeup water while automatically holding boiler TDS at target.

Not every heat recovery idea suits every boiler. Sulphur content, return water temperature, draft, materials and controls all decide whether a given unit saves fuel or corrodes a stack. A condensing unit fitted to a fuel with meaningful sulphur content, or fed water too warm to condense against, returns a fraction of the brochure figure. Our boiler economiser and energy efficiency page sets out the full range, including the combustion and controls upgrades described above.

For operators comparing options, the question is not peak efficiency at full load. The question is seasonal operating efficiency: how the boiler performs at the loads the plant actually runs.

Load control, sequencing and cycling

A boiler can test well and still run badly, because a test holds a steady load and a plant does not.

Burner cycling is the single biggest reason in-service efficiency lands at 70% to 75% against a design figure of 80% to 85%. The usual cause is a boiler oversized for the real heat or process load, whether from original over-sizing, building efficiency upgrades, boiler upgrades, or all three together. An oversized boiler cycles constantly, and cycling inflates the fixed radiation and convection losses that grow as a percentage of input as firing rate falls.

Most plants carry variable demand: batch processes, washdowns, sterilisers, heating loads, start-ups, shutdowns, weekend operation, seasonal swing. Sequencing decides how well the plant absorbs it. Practical actions, in the order they usually pay:

1. Match lead and lag boilers to the actual measured load, not the nameplate
2. Specify real turndown capability rather than peak output
3. Avoid running several boilers together at poor part-load
4. Review pressure setpoints and remove unnecessary margin
5. Use controls that prevent short cycling, and trend burner starts per hour
6. Stabilise steam demand where the process allows
7. Keep sensors and actuators maintained and calibrated

Lowering steam pressure reduces distribution and flash losses on some systems, but only where the process genuinely allows a lower pressure. Steam quality, control valve authority, heat exchanger sizing and product performance all need checking first. Efficiency never justifies risking production safety or product quality.

Sizing is a design decision operators inherit. Where a boiler cycles because it is twice the size the plant needs, no amount of tuning fixes the underlying problem, and the answer is a sizing review before the next capital replacement rather than after.

Maintenance that protects efficiency

Boiler efficiency does not hold after commissioning. Efficiency drifts. Burners wear. Sensors drift. Tubes foul. Insulation gets damaged. Traps fail. Linkages loosen. Control valves pass. Operators inherit settings nobody remembers setting.

A boiler maintenance programme is the mechanism that protects a measured efficiency baseline against that drift. The high-value tasks are combustion testing and burner tuning, linkage and damper inspection, gas train and flame safeguard checks, fireside cleaning, waterside inspection, water chemistry review, blowdown valve inspection, steam trap surveys, insulation repairs, economiser inspection, and control calibration.

One habit separates maintenance from energy management: recording before-and-after readings. For example, a burner tune logged as 6.2% flue gas oxygen before and 3.8% after is a defensible saving, while the same tune with no readings is just an invoice.

Operator competence sits alongside the hardware. Unattended and high risk work boiler operation in Australia carries licensing requirements, and a licensed operator who understands the readings will hold a tuned boiler at setpoint far longer than one who does not. O’Brien Energy delivers accredited boiler operator training as RTO #45484.

An efficiency checklist for operators

A boiler efficiency checklist is a tiered routine that turns engineering judgement into the same set of checks on every shift. For example, a rising stack temperature caught on a daily round is a fireside cleaning task, while the same trend found only at annual shutdown has already cost a year of fuel at 2% to 4% below baseline. Adapt each tier to the boiler type, site procedure, statutory requirements and manufacturer instructions.

Daily. Record steam pressure, load and fuel meter readings. Check feedwater temperature, water level stability, stack temperature against trend, condensate return temperature and blowdown operation. Review burner operation and listen for unusual combustion noise. Look for steam leaks and damaged insulation.

Weekly. Review fuel use against production output, plus oxygen and carbon monoxide readings. Check burner modulation pattern and the number of starts and stops. Inspect visible flue and casing condition. Review condensate return, chemical dosing and water test results. Inspect steam traps in critical service.

Monthly. Compare stack temperature at similar load. Review blowdown rate and TDS control. Inspect burner linkages and review pressure setpoints. Check economiser approach temperature where data exists. Review makeup water consumption and condensate losses. Identify leaking valves and traps.

Annual or planned shutdown. Run a full combustion tune across the firing range. Inspect and clean the fireside, then inspect the waterside and the economiser. Calibrate controls and inspect burner components. Complete the safety system checks, an insulation audit and a steam trap survey. Then assess efficiency against the recorded baseline.

A practical path to lower fuel cost

A boiler efficiency project is a structured sequence of eight steps, and the sequence matters more than the budget. Fuel invoices show the pain. Plant data shows the cause. For example, a plant that buys an economiser at step 5 before checking combustion at step 2 often finds the economiser recovering heat that better burner tuning would have saved for a fraction of the cost.

1. Confirm the baseline. Fuel use, steam output, operating hours, load profile, feedwater temperature, blowdown rate, stack data.
2. Check combustion first. Oxygen, carbon monoxide, stack temperature and burner stability across the full firing range, not only at high fire.
3. Inspect heat transfer condition. Fireside and waterside fouling, scale, soot, cleaning history.
4. Review blowdown and water treatment. TDS control, blowdown rate, feedwater quality, condensate return, makeup volume.
5. Assess heat recovery. Economisers, blowdown recovery, flash steam recovery, condensate upgrades.
6. Review controls and sequencing. Turndown, setpoints, cycling frequency, sensor calibration, multi-boiler logic.
7. Build the business case. Measured data only, including maintenance, downtime, installation and risk alongside the fuel saving.
8. Verify after implementation. Retest under comparable conditions and keep the baseline alive.

Steps 2 through 4 cost little and frequently recover more than a capital upgrade would. Two habits undo the whole sequence: judging performance from fuel bills alone, which hides a 4% loss for a full quarter, and skipping the step 8 retest, which turns a measured saving back into an assumption.

Frequently asked questions

What is boiler efficiency?

Boiler efficiency is the percentage of fuel energy converted into useful steam or hot water. Two methods produce the figure. The direct method compares useful heat output against fuel energy input. The indirect method subtracts measured heat losses from total fuel input.

A well-maintained industrial boiler on natural gas runs 80% to 85%. Across a real Australian load profile, most plants achieve only 70% to 75%, because burner cycling and excess air erode the design figure once production varies. For example, a boiler tested at 84% under steady load can average closer to 74% over a month of batch operation. Every point of the gap is fuel bought and vented. O’Brien Energy assesses boiler efficiency against AS 2593 operating discipline and a stated calorific value basis, so successive tests stay comparable.

How do you calculate the efficiency of a boiler?

Divide useful heat output by fuel energy input, then multiply by 100. The direct method formula is: boiler efficiency (%) = useful heat output ÷ fuel energy input × 100.

For example, 8,000 kW of useful steam output divided by 9,500 kW of fuel input equals 84.2% boiler efficiency. Useful output for a steam boiler is steam mass flow multiplied by the enthalpy rise from feedwater to steam. Fuel input is fuel flow multiplied by calorific value.

Two details decide whether the result means anything. First, state whether the calorific value is gross or net, because the two bases differ by around 10% on natural gas. Second, state the measurement boundary: boiler only, boiler plus economiser, or complete steam system. Without both, two efficiency figures cannot be compared.

What is a good boiler efficiency?

A well-maintained industrial boiler with an economiser and modern combustion controls typically reaches 80% to 85% on natural gas. In-service efficiency across a real load profile runs lower, at 70% to 75%, mostly because of burner cycling on oversized plant.

Anything below 70% at steady load points to a specific, findable fault rather than general wear. The usual candidates are excess air well above the 24% to 30% commissioning band, a fouled tube bank, an over-open blowdown valve, or cold feedwater from poor condensate return.

Judge the figure against the plant’s own history rather than a published benchmark. A boiler holding 82% for three years is managed. A boiler drifting from 84% to 78% over one year is telling an operator exactly where to look, regardless of how the number compares to any industry average.

How can I improve boiler efficiency in an industrial plant?

Measure the baseline first, then work in cost order rather than capital order.

Start with combustion. Tune the burner and bring excess air down toward the 24% to 30% band, then fit a variable speed drive and O2 trim so the fuel-to-air ratio holds at part load instead of only at high fire. Clean fireside and waterside heat transfer surfaces. Control blowdown with automatic TDS control rather than manual margin.

Next raise feedwater temperature by recovering condensate, repairing steam traps and insulating bare valves and flanges. Then assess heat recovery: an economiser can improve overall boiler efficiency by up to 10%, with typical fuel savings of 5% to 10%. Finally review sequencing to stop short cycling, and retest under comparable conditions to verify the saving.

What is combustion efficiency?

Combustion efficiency measures how completely the burner converts fuel into heat inside the furnace. Perfect combustion on natural gas needs a fuel-to-air ratio of 9.7:1, with all oxygen consumed and all fuel burned.

No plant operates at the theoretical ratio. For safety and maintenance margin, an industrial burner is commissioned with a minimum of 24% to 30% excess air. Excess air, fuel-air mixing, burner condition, draft, flame stability and carbon monoxide level all move combustion efficiency.

In practice, combustion efficiency is measured by flue gas analysis: oxygen and carbon monoxide readings taken across low, mid and high fire. A burner tuned only at high fire can perform well at the test point and poorly through the rest of the firing range, which is where most industrial boilers spend their operating hours.

Why does excess air increase fuel cost?

Excess air is heated by the fuel and then carried out of the stack, so any air beyond what safe combustion requires is gas spent warming the atmosphere.

Some excess air is essential. Too little produces unburnt fuel and carbon monoxide, which is toxic and explosive, so burners are commissioned with a 24% to 30% minimum margin.

The cost usually appears at low fire. A burner with a fixed-speed combustion air fan delivers full high-fire air volume even when the burner modulates down, pushing excess air far above the design band and driving efficiency down as demand falls. A variable speed drive plus O2 trim corrects the ratio continuously and recovers most of that loss. Trending flue gas oxygen at low, mid and high fire is what makes the problem visible before the gas bill does.

What causes boiler heat loss?

Boiler heat loss is the fuel energy that never reaches the steam, and the largest single path is hot flue gas leaving the stack, made worse by excess air and by fouling that blocks heat transfer into the water.

Seven further paths account for most of the remainder. First, blowdown discharge carrying hot treated water out of the boiler. Second, radiation and convection from casing and uninsulated valves. Third, short cycling on oversized plant. Then incomplete combustion, steam leaks, failed steam traps, and low condensate return forcing cold makeup water into the feed tank.

Rank the losses by size before spending anything, because stack loss and excess air usually dominate and are also the cheapest to correct. For example, one un-insulated DN 100 globe valve in a 160°C system wastes about 629 cubic metres of natural gas a year, while pulling excess air from 45% back to the 30% commissioning band on a large boiler saves many times that.

Does an economiser improve boiler efficiency?

Yes. An economiser captures waste heat from flue gas to preheat boiler feedwater, and can improve overall boiler efficiency by up to 10%. Typical fuel savings run 5% to 10%, with payback commonly inside one to three years.

Suitability depends on load profile, stack temperature, fuel type, feedwater temperature, available space, controls and corrosion risk, so a technical assessment should precede any purchase. A single-stage feedwater economiser suits steam and hot water plant at all design pressures. A condensing economiser recovers considerably more heat but only where a cool liquid stream below roughly 50°C is available, and only on natural gas.

Sulphur content and return water temperature decide the outcome. An economiser fed water too warm to condense against returns a fraction of the brochure figure.

How often should a boiler be tuned?

The right tuning interval is a function of site load, fuel, burner type, operating hours, regulations and manufacturer guidance rather than a fixed calendar date. As a working baseline, industrial boilers on continuous duty benefit from combustion testing at least annually, folded into the planned maintenance and statutory inspection cycle.

Four triggers justify an unscheduled retune. First, flue gas oxygen or carbon monoxide readings drifting from commissioned values. Second, any gas train, burner or control component changed or replaced. Third, fuel use rising against production output. Fourth, burner starts per hour climbing above the normal pattern.

For example, a burner commissioned at 3.5% flue gas oxygen and now reading 6.5% has lost efficiency worth retuning immediately, well before the next scheduled service. Log the readings each time so drift becomes visible across years instead of being rediscovered at every visit.

What data should operators record?

The core efficiency record is a set of 12 readings: fuel use, steam output, steam pressure, feedwater temperature, stack temperature, flue gas oxygen, carbon monoxide, blowdown rate, condensate return rate, makeup water volume, burner starts per hour, and every major maintenance event.

Record all 12 at comparable load, because a reading taken at high fire cannot be compared with one taken at low fire. Note the date, the load condition and the instrument used alongside each value.

Recorded consistently, the 12 readings turn maintenance from unverifiable cost into measurable saving. For example, a stack temperature climbing 20°C at constant load and constant excess air exposes fouling months before the 2% to 3% efficiency loss becomes visible on a gas bill. A documented before-and-after set is also what justifies the next capital request at budget time.

Book an efficiency assessment with O’Brien Energy

An efficiency assessment is a measured review of the whole boiler room rather than a single component. Fuel. Air. Water. Steam. Condensate. Controls. Maintenance. Heat recovery. Closing the typical gap between 70% to 75% in service and a design 80% to 85% almost always takes several small corrections rather than one purchase.

O’Brien Energy brings engineering-led boiler experience to that full picture, from flue gas analysis and combustion tuning through maintenance and engineering review to economisers, heat recovery and plant optimisation. We hold parts on hand, respond 24/7 nationwide, and back the work with accredited operator training as RTO #45484.

If rising gas costs are putting pressure on your site, book an efficiency assessment or call 1300 771 759. We will identify the real losses, rank them by payback, and give you a costed path to lower fuel use.