Heat Exchanger Troubleshooting: Causes & Fixes

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Problems on this page:

Poor heat transfer Internal leak / cross-contamination High pressure drop Gasket leaks to the outside Tube failures from vibration or erosion Corrosion Temperature control unstable Damage from freezing or water hammer Steam heated exchanger stalling

Poor heat transfer

Hits OEE: Performance

Symptoms: Outlet temperatures miss their targets, more steam or cooling water is needed, the duty falls over time.

Fouling, scale or biofilm on the surfaces

Clean mechanically or chemically and fix the water treatment that let it build.

Air or non-condensable gas trapped on the steam or water side

Vent the exchanger as the maker describes.

Low flow or poor distribution on one side

Check pumps, strainers and valves on both sides.

Flow far below the design

Check the operating flows against the design.

Prevention: Approach temperatures trended so fouling shows before it limits production.

Internal leak / cross-contamination

Hits OEE: Quality

Symptoms: One fluid contaminating the other, pressure or level cross-talk.

Tube or plate failure

Pressure-test to find the failed tube/plate; plug or replace.

Failed gasket (plate type)

Replace gaskets; re-torque the plate pack to spec.

Prevention: Periodic integrity testing, gasket renewal, corrosion control.

High pressure drop

Hits OEE: Performance

Symptoms: Rising differential pressure across the unit, reduced flow.

Fouling or scaling

Clean (chemical or mechanical); treat the fluid.

Partial blockage / debris

Strip and clear; fit upstream strainer.

Flow above design

Check the flow rate against the design envelope.

Prevention: Cleaning schedule, upstream filtration, flow monitoring.

Gasket leaks to the outside

Hits OEE: Availability

Symptoms: Drips or sprays from a plate heat exchanger pack.

Gaskets aged or hardened

Replace the gaskets.

Pack not tightened to the right dimension

Tighten to the maker's pack dimension.

Gaskets attacked by cleaning chemicals

Check the chemicals against the gasket material.

Pressure spikes

Check valves and pumps for shocks.

Prevention: Gasket replacement planned before they age out.

Tube failures from vibration or erosion

Hits OEE: Availability

Symptoms: Leaking tubes near the inlet or at the baffles.

Shell side flow above design

Check flows against the design.

Missing impingement protection at the inlet

Fit an impingement plate.

Baffles damaged

Inspect the bundle.

Prevention: Tube inspections at shutdowns.

Corrosion

Hits OEE: Availability

Symptoms: Pitting, leaks, rust deposits.

Material not suited to the fluids

Check materials against the fluids.

Chlorides in the water

Check the water chemistry.

Mixed metals in contact

Isolate dissimilar metals.

Prevention: Water chemistry tested on schedule.

Temperature control unstable

Hits OEE: Quality

Symptoms: The outlet temperature swings.

Control valve oversized

Check the valve sizing.

Sensor in the wrong place

Move the sensor.

Condensate backing up on the steam side

Check the steam trap and condensate line.

Prevention: Loop performance reviewed.

Damage from freezing or water hammer

Hits OEE: Availability

Symptoms: Split plates or tubes, bulged headers.

Water left in an idle exchanger in frost

Drain it or keep water flowing.

Condensate hammer on a steam heated exchanger

Drain condensate properly.

Valves closing fast

Slow the valve actuation.

Prevention: Winter checklist for idle equipment.

Steam heated exchanger stalling

Hits OEE: Performance

Symptoms: Heating falls off at low loads, condensate backs up, temperature control hunts.

Steam pressure in the exchanger drops below the condensate back pressure

Use a pump trap or pumped condensate return.

Trap sized for the wrong pressure

Size the trap for the lowest working pressure.

Condensate line rising straight after the trap

Re-route or pump the condensate.

Missing vacuum breaker

Fit a vacuum breaker so condensate can drain at low pressure.

Prevention: Condensate drainage reviewed when loads change.

Guidance only. Always follow lockout/tagout and your site's safe-work procedures, and verify against OEM manuals before acting.

Stop the same fault coming back

Recurring heat exchanger stops usually trace to a cause you cannot see by hand. The partner we recommend is Fabrico: it tracks OEE and downtime live from PLCs, IoT sensors or AI cameras; where cameras are fitted, the video of a stop sits next to its machine data so the cause can be reviewed; and a technician opens the work order from the stop in the same system. Data is hosted in the AWS EU region, and Fabrico and the company behind it hold ISO/IEC 27001, ISO/IEC 20000-1 and ISO 9001.

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Methods that cut recurring stops: the six big losses · root cause analysis · preventive vs predictive maintenance · TPM · SMED & changeover