Heat Exchanger Problems That Hurt Efficiency—And How to Fix Them
In any commercial or industrial boiler system, the heat exchanger is one of the most critical components. It’s responsible for transferring heat from combustion gases to the water or steam used throughout your facility. When that process is disrupted—whether by scale, corrosion, or mechanical failure—your boiler’s efficiency plummets, energy costs rise, and system reliability suffers.
Over time, even minor heat exchanger issues can lead to major performance losses or even full system failure if not addressed. At Houston Boiler Works, we specialize in inspecting, repairing, and replacing commercial and industrial heat exchangers across Texas. This guide outlines the most common problems we see and how to fix them before they cost you thousands in fuel and downtime.
What Does a Heat Exchanger Do in a Boiler System?
A boiler’s heat exchanger is where thermal energy is transferred from the burner’s hot combustion gases to the water or steam that circulates throughout your facility.
The efficiency of this process has a direct impact on:
- Fuel-to-heat conversion rates
- Operating pressure and temperature stability
- Emissions and environmental compliance
- Energy costs and system performance
When heat transfer is impeded, the system has to work harder to deliver the same output, wasting energy and stressing equipment.
In Texas, where mineral-rich water and variable operating conditions are common, heat exchanger performance degrades quickly without regular inspection, cleaning, and water treatment.
6 Common Heat Exchanger Problems That Reduce Efficiency
Here are the most frequent issues we encounter in commercial and industrial boiler systems—and what you can do about them.
1. Scale Buildup
What it is: Hard water introduces calcium and magnesium into the system, which form solid deposits (scale) inside the heat exchanger.
Why it matters: Scale acts as an insulator, reducing heat transfer and causing uneven thermal expansion. Just 1/8" of scale can reduce efficiency by 10–15% and lead to overheating.
How to fix it:
- Install a commercial water softener system
- Schedule regular descaling and internal cleaning
- Monitor hardness levels and perform periodic water testing
2. Fouling from Soot or Combustion Byproducts
What it is: Poor combustion or air-to-fuel imbalance leads to soot deposits on the fire side of the heat exchanger.
Why it matters: Fouling reduces surface area for heat transfer and creates hot spots that accelerate metal fatigue or cracking.
How to fix it:
- Conduct annual combustion analysis and burner tuning
- Check for proper draft, venting, and burner calibration
- Clean heat exchanger tubes or plates on a scheduled basis
3. Corrosion
What it is: Corrosive agents—like oxygen, low pH, or acidic condensate—attack internal metal surfaces, especially in the presence of untreated water.
Why it matters: Corrosion leads to pitting, leaks, weakened joints, and potential structural failure of the heat exchanger.
How to fix it:
- Replace affected tubes or tube sheets
- Monitor and adjust water chemistry using chemical treatment plans
- Ensure proper deaeration and install oxygen scavengers
4. Flow Restrictions or Blockages
What it is: Sludge, rust, or mineral debris can block flow channels within the heat exchanger, restricting circulation.
Why it matters: Poor flow causes uneven heating, pressure drops, and local overheating—all of which reduce efficiency and increase stress on pumps and valves.
How to fix it:
- Flush the system and remove accumulated sludge
- Use inline strainers and filters
- Inspect for signs of flow imbalance or water hammer
5. Gasket Failures
What it is: Heat, chemical exposure, and age degrade the gaskets that seal water and combustion passages in shell-and-tube or plate heat exchangers.
Why it matters: Failed gaskets can lead to internal leaks, cross-contamination, and unsafe operating pressures.
How to fix it:
- Inspect gaskets during each service interval
- Replace gaskets with high-temperature, chemically resistant materials
- Avoid overtightening and use torque specifications
6. Tube Erosion or Cracking
What it is: Continuous high-pressure and high-temperature operation, combined with poor water quality, erodes internal tube surfaces or causes cracking.
Why it matters: Cracked or eroded tubes reduce performance, risk sudden leaks, and may force a full shutdown.
How to fix it:
- Perform ultrasonic thickness testing
- Replace damaged tubes using ASME-certified welding
- Monitor water velocity and quality to reduce mechanical wear
How Houston Boiler Works Repairs and Maintains Heat Exchangers
At Houston Boiler Works, we deliver full-service heat exchanger maintenance and repair for commercial and industrial systems across Texas. Our team is ASME Code-certified, and all work is performed in compliance with state and national safety standards.
Our services include:
- Ultrasonic testing for wall thickness and erosion
- Tube sheet cleaning and recoating
- Plugging or replacement of leaking or failed tubes
- Gasket inspection and full resealing
- Emergency leak repair and bypass piping
- Full heat exchanger removal and replacement, if required
Whether your facility uses a shell-and-tube, finned, or plate heat exchanger, we have the expertise and equipment to restore performance and reliability.
Case Study: Heat Exchanger Restoration in Austin
In July 2023, a university campus in Austin began experiencing overheating alarms and rising natural gas bills. Our technicians inspected the boiler system and found:
- Scale deposits on 70% of internal tube surfaces
- Two leaking tubes caused by internal corrosion
- Flow imbalance due to a partially blocked return line
We performed a full descaling, replaced the leaking tubes, and flushed the system. Post-repair efficiency testing showed a return to 92% thermal efficiency, saving the university an estimated $8,500 annually in fuel costs alone.
Frequently Asked Questions
How often should heat exchangers be cleaned?
At least once per year for most commercial systems. For facilities with high water hardness or continuous operation, we recommend quarterly inspections and cleaning.
Can heat exchangers be repaired, or do they need full replacement?
In many cases, yes—individual tubes, gaskets, or flow sections can be repaired or replaced. We only recommend full replacement when damage is widespread or structural integrity is compromised.
How can I tell if my heat exchanger is losing efficiency?
Look for:
- Rising fuel costs
- Inconsistent temperatures
- Pressure swings
- Alarms related to combustion or flow
Regular inspections help detect these issues before they impact system performance.
Do you service all types of heat exchangers?
Yes. We work with:
- Shell-and-tube systems
- Plate heat exchangers
- Finned coil exchangers
- Custom and OEM models
Get Professional Heat Exchanger Service in Texas
If your boiler system is underperforming, don’t wait for a full breakdown to take action. Houston Boiler Works provides fast, expert service to repair, replace, or upgrade your heat exchanger—reducing downtime and improving energy efficiency.
Serving Texas facilities in Houston, Dallas, Fort Worth, Austin, San Antonio, and beyond.
