Effective Cleaning Methods for Heat Exchangers: Techniques, Intervals, and Best Practices

Mr. Toey

Over time, all heat exchangers are affected by fouling, which leads to reduced heat transfer efficiency, increased pressure drop, and higher energy costs. Selecting the proper cleaning method is critical to maintaining system performance, extending service life, and ensuring process safety.

This article explores the most widely used heat exchanger cleaning techniques, their advantages and limitations, recommended cleaning intervals, and materials compatibility—helping you build a smart maintenance strategy.

Why Cleaning Is Essential

According to Wikipedia – Heat exchanger fouling, fouling is the accumulation of unwanted material on heat transfer surfaces. Common fouling types include:

Scaling (e.g., calcium carbonate in water systems)
Particulate fouling (dust, sediment, sludge)
Chemical fouling (polymer or chemical film buildup)
Biological fouling (biofilms, algae)
Corrosion products

Uncontrolled fouling can reduce thermal efficiency by 20–40%, shorten equipment lifespan, and increase operational risk.

Common Heat Exchanger Cleaning Methods

1. Mechanical Cleaning (Manual or Automated)

Best for: Shell-and-tube heat exchangers with removable bundles or U-tubes.

Techniques include:

Tube brushing or rod cleaning
High-pressure water jetting
Pneumatic tube punching

Pros:

No chemical handling
Ideal for heavy scaling and hard deposits
Reaches internal surfaces

Cons:

Requires shutdown and disassembly
May not reach complex geometries

2. Chemical Cleaning (CIP – Clean-in-Place)

Best for: Plate heat exchangers and systems requiring hygienic standards.

Typical chemicals:

Acidic descalers (e.g., citric, sulfuric acid) for scaling
Alkaline cleaners for grease, biofilms
Biocides for microbiological fouling

Pros:

Non-invasive; no need to disassemble equipment
Cleans internals thoroughly
Efficient for smooth and compact exchangers

Cons:

Must manage waste and neutralization
May not remove thick or hard scaling
Material compatibility must be verified

See Wikipedia – Clean-in-Place

3. Hydroblasting / High-Pressure Jetting

Best for: Industrial shell-and-tube units with moderate to heavy fouling.

Key features:

Pressures from 5,000 to 20,000 psi
Robotic or manually guided jets

Pros:

No chemicals involved
Very effective on large-scale fouling
Short cleaning time with trained personnel

Cons:

High noise, water consumption
Safety precautions required

4. Ultrasonic Cleaning (Less Common)

Best for: Small heat exchangers, medical and precision systems.

Principle: Uses cavitation bubbles generated by high-frequency sound waves to dislodge contaminants.

Pros:

Delicate and precise
No abrasive contact

Cons:

Limited to smaller units or components
Higher equipment cost

How Often Should Heat Exchangers Be Cleaned?

There is no universal schedule—it depends on:

Fluid type (dirty vs. clean service)
Operating hours
Water chemistry or contamination risk
Design (PHE vs. STHE)

General guidelines:

Application	Typical Cleaning Interval
Food & beverage (CIP)	Every 2–4 weeks
HVAC / Chiller	Every 6–12 months
Oil & Gas Processing	Every shutdown / turnaround
Boilers / Steam	1–2 times per year
Offshore Systems	As per inspection cycles

DLSS Tips: Designing for Cleanability

When designing or selecting a heat exchanger, consider:

Tube material: Stainless steel, Duplex, and Titanium resist scaling and fouling
Surface finish: Polished or bright-annealed surfaces reduce adhesion
Removable tube bundles: Simplifies mechanical cleaning
Flow velocity: High enough to minimize deposition
CIP-compatible design: Especially for food, pharma, and HVAC

More on materials: DLSS Heat Exchanger Tubing Solutions

Frequently Asked Questions (FAQ)

Q1: Can I use acid to clean stainless steel tubes?
Yes, but only compatible acids like citric or phosphoric. Avoid high-concentration HCl or sulfuric acid on 304/316L.

Q2: What are the signs my heat exchanger needs cleaning?
Reduced heat transfer, increased pressure drop, abnormal energy consumption, or inspection showing deposits.

Q3: What tube materials are easiest to clean?
316L, Duplex, and Titanium offer superior resistance to both fouling and chemical attack.

Q4: Can I clean U-bend tubes with mechanical brushes?
Yes, but flexible or rotary brush systems are needed due to the curved geometry.

Contact Us

DLSS supports global clients with high-performance tubing designed for durability, cleanability, and chemical resistance. Whether you operate in clean service or heavy-fouling environments, we offer: