In Charge Of Boiler Maintenance? Here’s What You Need To Know

Boiler MaintenanceThe industrial revolution was built on boilers. They are still used for various applications to this day. In fact, it would be hard to find a facility without a single boiler somewhere on its premises.

Boilers play an important role in industrial settings and operate around the clock. That’s why boiler maintenance requires a disciplined approach.

If you are in charge of the maintenance of boilers, we have much important information to share.

Boiler maintenance checklists

Maintenance tasks must be done carefully and consistently. Checklists are helpful tools that ensure technicians perform every task and address every detail they need to. 

Each boiler system will have its own routine maintenance tasks that must occur daily, weekly, and semi-annually. The following sections cover common boiler service needs at different time intervals. 

Remember that the proper maintenance schedule for your boiler should be based on the boiler type, OEM guidelines, maintenance history, and the conditions in which the boiler operates. Consult those resources to supplement and individualize these checklists for your equipment. 

Daily maintenance checklist

Perform the following tasks daily.

  • Open the drainage and blow out water from the pipes when the boiler is not in use. 
  • Keep track of boiler parameters such as fuel consumed, temperature, and pressure. This ensures the boiler system is operating as expected.
  • Regularly check the pressure readings for output steam as well as the water inlet. 
  • Observe the furnace periodically through the sight port. Look for sooting and flame abnormalities.
  • Check the various venting and drainage systems for blockages.
  • Monitor the characteristics of the water used in the boiler. Take samples and check water hardness, the minerals present, etc.

Weekly maintenance checklist

Check the following every week.

  • Check fuel supply and related pipes, tubes, and valves.
  • Perform evaporation tests to ensure proper operation.
  • Check the boiler for leaks, including water, steam, and exhaust gases.
  • Check operating controls to ensure normal functioning. 
  • Check indicators and safety features to ensure they are working properly.
  • Check for unusual noises and vibrations.

Checklist for Creating a Preventive Maintenance Plan

Following a consistent Preventive Maintenance Plan can make life easier. Use this checklist to create your own!

Monthly maintenance checklist

Complete the following checks on a monthly basis.

  • Check boiler components for visible cracks and other damages.
  • Clean the combustion chamber, chimney, and exhaust stack.
  • Check the boiler’s ignition system.
  • Check for hotspots on the boiler’s exterior.

Semi-annual maintenance checklist

Some maintenance tasks need to be done in six-month intervals, including:

  • Check for scaling inside the boiler components.
  • Assessing corrosion levels in the boiler and transport tubes.
  • Checking the operational characteristics of various boiler pumps.
  • Performing non-destructive testing to test boiler components materials.
  • Checking the condition of wires, switches, and other electrical components

Creating a routine maintenance schedule for industrial boilers

Boilers must be regularly maintained to ensure safety and energy efficiency. Creating a preventive maintenance schedule, particularly for industrial boilers, is critical for avoiding boiler failure.

The boiler manufacturer will provide a standard maintenance schedule for you to start from that you should stick to closely. Then, the maintenance schedule must be adjusted over time based on the condition and usage of the boiler. 

Customizing your maintenance schedule

When customizing your industrial boiler maintenance schedule, you must take several things into consideration. 

Water characteristics such as:

  • Hardness
  • pH level
  • Impurities

Environmental factors such as:

  • Humidity
  • Temperature
  • Boiler location

Factors impacted by other plant equipment such as:

  • Spillage 
  • Debris 
  • Changes to environmental conditions (heat, humidity, vibration, etc.)

Getting expert input on your maintenance schedule

The boiler maintenance schedule should be created by experienced professionals who work together to prioritize daily, weekly, and monthly tasks.

Experts to include in this process are:

  • The boiler manufacturer
  • Operations engineers and technicians
  • Reliability
  • Maintenance technicians

For an added layer of safety, you can create preventive maintenance checklists and standard operating procedures for individual boiler maintenance tasks.

Characteristics of different boiler types

Here is a quick breakdown of the more common types of boilers based on energy sources, tube contents, tube numbers, furnace positions, and circulation methods.  Understanding these characteristics will make troubleshooting boiler problems that much easier.

Energy source

Boilers can use a variety of fuels as the source of their energy including: 

  • Wood
  • Charcoal
  • Coal
  • Oil
  • Natural gas
  • Electricity

Contents in tubes

Based on the type of fluid flowing through the boiler’s tubes to create heat, we can differentiate between two types of boilers.

  • Fire-tube boilers: Hot gases and fumes generated by combustion are passed through the boiler tubes to heat up water.
  • Water-tube boilers: Water is heated by passing through tubes surrounded by hot gases, fire, and heat from the combustion chamber.

Number of tubes

Boilers can also be classified depending on the number of tubes in the boiler shell.

  • Single tube boilers: A single tube that can be either a fire tube or a water tube. Single-tube boilers generally have a low capacity.
  • Multi-tubular boilers: Multiple tubes that heat a larger quantity of water in a shorter time for high-efficiency needs.

Furnace position

Another way to classify boilers is based on the position of the combustion chamber or heater.

  • Internally fired boilers: Fuel combustion takes place in a specific chamber within the boiler shell.
  • Externally fired boilers: Fuel combustion happens outside the boiler shell.

Of course, some boiler designs do not include a furnace. For example, electric boilers do not burn any type of fuel, and therefore do not need a combustion chamber.

Circulation methods

Water and steam can be circulated throughout a boiler using different methods: 

  • Natural circulation boilers: Convection currents and gravity are used to move fluids.
  • Forced circulation boilers: The fluid is moved using pumps or other external forces.

Critical boiler components

Boilers consist of many components with unique functions and maintenance requirements. Here are the different components of an industrial boiler system and their respective maintenance considerations.

Follow these tips for each component, and you will avoid (or delay) some of the most common and costly boiler repairs. 


This is where the heat happens. Fuel, air, and sparks meet at the burner to create the energy used to heat water. 

How problems arise:

Inefficient combustion leads to wasted fuel. Clogged burners lead to fuel leakage, which can cause uncontrolled fire and explosions. 

How to avoid them:

Conduct periodic burner inspections, including the electrical and mechanical connections. Ensure there are no fuel leakages. 

Check for corrosion on the surface, the fuel pipes, and other fittings of the boiler. Regularly check for debris blocking the fuel source or the fresh supply of air for combustion.

Combustion chamber

The combustion chamber is the safe and isolated space where fuel combustion occurs, generating energy and heat. 

How problems arise:

This is one of the critical boiler areas.  Naturally, it can also generate many hazards if maintenance is not up to par. Soot and other debris in the combustion chamber can lead to a drop in efficiency. Unwanted objects in the combustion chamber are also a cause for fire hazards.

How to avoid them:

Clean up the combustion chamber periodically. Ensure air intake is not blocked. Check periodically for cracks or corrosion on the materials lining the combustion chamber. 

Heat exchanger

The heat exchanger is where the combustion-generated heat gets transferred to the water. In most boiler designs, the heat exchanger basically consists of fire/water tubes that carry fluids. 

How problems arise:

The surface of the heating system is in contact with fluids of different temperatures. This can cause various material distortions. 

How to avoid them:

Check for cracks or other physical changes in materials. You can also rely on various non-destructive testing methods – like ultrasonic testing and eddy current testing – to check tube health.


The switches, knobs, sensors, and other components for monitoring and controlling the operations can also be considered critical components of the boiler. Control failure can lead to a variety of results ranging from minor to catastrophic. 

How problems arise:

Because controls are typically electrical or supported by more advanced technology, electrical issues or outdated software could cause problems.

How to avoid them:

Check electrical connections on the control elements periodically. If the software is used in control systems, make sure the latest update is installed. Additionally, make sure to follow proper cyber security protocols. Replace hardware components according to the schedule provided by the OEMs.

Transport lines

Boiler water, hot water, and steam are all transported using pipes, tubes, or other mechanical parts known as transport lines transport lines. 

How problems arise:

Cracks or leaks can form in transport lines over the life of the machine, causing inefficiency.

How to avoid them:

Regularly check the transport lines for corrosion and cracks. Ensure there is no pressure loss in the pipes and tubes. On top of that, make sure that there are no obstructions hindering fluid flow.

Exhaust stack

The exhaust stack consists of chimneys and associated equipment used to remove the gases and fumes produced by fuel combustion. The exhaust stack is designed so that no poisonous gases remain in the plant. 

How problems arise:

Broken exhaust pipes and chimneys can cause exhaust gas leakage. Soot and other accumulated debris can decrease exhaust efficiency and, consequently, boiler efficiency as well.

How to avoid them:

Check the pipes and tubes in the exhaust stack for faults. Periodically check for poisonous gases to ensure that the exhaust stack is working properly. Schedule clean-ups regularly to remove soot and other debris.

Common issues with industrial boilers

Despite all the different types of industrial boilers, there are some common problems that plague them all. By keeping an eye out for these common problems, you will know when your boiler needs servicing.  You will also catch small issues before they get too big. 


Leaks are one of the most common boiler troubles. Leaks can happen in various transport components as well as the boiler shell itself. Whenever there is a drip, it is time for an inspection.


Corrosion is another universal problem with boilers. Since the metallic parts and components interact with water, they are prone to corrosion. This damages various boiler components and can cause them to fail if preventive steps are not taken.


Water used in the boiler contains minerals and other impurities. These impurities can form scaly deposits on different boiler parts. Their appearance is similar to fish scales – hence the name.


When water is heated, solid impurities can rise up and foam up over the boiling water. This causes a drop in boiler efficiency. The solid waste can also be carried away with steam and form deposits on other boiler parts.

Low pressure

Low water or steam pressure is another common problem. This is generally an indication of other problems within the boiler.


In steam boilers, water molecules can get carried along with steam. The result is called wet steam. This is called “priming” and can cause many other problems down the line. Priming happens due to improper boiler design, high water levels, water contaminants, and improper usage. 

Unusual noises

If you have been around them for a while, you know what noises boilers or radiators make under normal conditions. Loud bangs and whistling noises are usually not among them. Such symptoms clearly indicate underlying problems.

The dangers of poor boiler maintenance 

Boilers are one of the most commonly used pieces of equipment in the industrial setting. But when you are dealing with combustible fuel, hot water, and steam held at very high pressure, you really need to know what you are doing.

A boiler failure can cause a large catastrophe, harming both life and property. That is why designers and engineers have devoted time and energy to improving their safety and durability. 

Don’t let this lead to complacency or neglect in your boiler maintenance program. Even with the improvements made over the years, the stakes are still too high. 

Take charge of industrial boiler maintenance

Boilers are one of the most critical pieces of equipment used in industrial operations. At best,  boiler failure will cause capital losses and operational disruptions. At worst, it will result in catastrophic damage, taking lives and destroying property. 

Creating comprehensive maintenance schedules is essential, but they are only effective if carried out meticulously. A CMMS like Limble has simple features that ensure consistent and meticulous execution of your maintenance plans. 

If you would like to learn more about how Limble can help you maintain industrial boilers or any other types of heavy machinery or company assets, give Limble CMMS a try. Reach out to our CMMS specialists, schedule a quick product demo, or even sign up for a free trial

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