One of the most common problems with commercial boilers is water leaks. While you may think that a few drops underneath the boiler might be a simple fix, please be cautioned that a leak can lead to significant damages within your boiler system, so it best to act quickly and efficiently.

We always recommend incorporating routine preventative maintenance practices as a company standard for operational excellence, but we understand that sometimes these things can happen and we want to prepare you should this situation arise. In this article, we will explain the common causes of boiler leaks along with solutions to repair boiler leaks for both the short- and long-term.

If you have a water leak within your boiler system, please contact Powerhouse immediately and we will send a technician to ensure proper safety measures are enacted.

How to Identify a Boiler Leak?

There are a few ways to detect if your boiler is leaking water, which we will identify so you can then determine your repair plan. As you may expect, a buildup of water around the base of your boiler is one of the most common ways to spot a leak, but it is not always that obvious to the eye. Fortunately, there are other things you can look into to identify the issue. You should check your boiler system for steam leaks along with any rust or deterioration of the jacketing and insulation material. Lastly, you can track the amount of water your boiler system uses with the water meter, and if you notice that water usage is rising, then you may, again, have an issue with a leaking boiler.

Boiler repair leaks

What Causes a Boiler to Leak Water?

Now that we know how to identify a boiler leak, we will describe the most common diagnoses to help you better identify the source of the problem. Understanding the root cause of the leaking water along with the make and model of the boiler will then allow you to determine the best course of action. Please consult with a service technician before moving full steam ahead with a remedy.


The pump is an integral part of your industrial boiler with its main function being that it constantly runs and circulates water throughout the entire boiler system. Because of the nonstop workflow, it is common for the pump valve or seal to break since the rubber seals can be hardened or destroyed by elements rapidly moving within the boiler system.

Depending on the amount of damage to the pump, you will have two options on how to repair the part. It is possible that you can simply reseal the pump with a gasket kit, yet there might be a need to replace the boiler pump entirely. In either case, we recommend that you connect with our partners at Boiler Geek, who can help source the part you need, quickly and efficiently.

Pump discharge piping


The pipes are the carriers that circulate water throughout the boiler system. It is possible that the pipes leading in and out of the boilers are the reason for your water leaks. This is likely caused by improper installation or the degradation of pipe connection due to corrosion over time. Either reason requires replacement of the part and proper installation.

Pressure Relief Valve

The pressure relief valve protects the boiler system from building up too much pressure. If the pressure is too high, then the boiler will release steam and water. Should this happen, there could be significant damage so it is important to identify and treat this issue as soon as possible.

Some possible repairs for the pressure relief valve are to remove lime or debris, reseal the valve or bleed the boiler. Of note, the pressure relief valve is regulated by ASME and is subject to inspections based on jurisdictional guidelines.


Rust and corrosion of the boiler vessel weaken the boiler system and allows water to escape. There is a good chance that the corrosion you see signifies that your boiler system is old and needs to be replaced. However, there is also the possibility that corrosion is a result of poor water quality. A feedwater system is supposed to remove harmful impurities that contribute to scale build-up in the boiler and associated piping and fittings. If you have an “improperly treated feedwater” condition, then you will notice scaling in the boiler internals, safety equipment and auxiliary pipings. As part of an ongoing service for water treatment, we can help you protect and maintain your boiler.

Thermal Fatigue

Thermal fatigue is another cause of boiler leaks that stems from an improperly regulating feedwater temperatures and quality. The first area to check is the feedwater coupling where the boiler is supplied water from the feedwater system. If the feedwater temperature is too low, high thermal shock will result in cracking of the welds on the coupling where the hot boiler water is contacting the low temperature feedwater. Moving to the internal of the boiler, one of the biggest concerns is the reduction of heat transfer in the internal components. The boiler tubes and tubesheets are the transfer mediums between the hot combustion gases and the boiler water. When the scale is built upon the boiler tubes and the tubesheets, then the heat transfer rate declines as the scale acts as an insulator instead of a conductor. As the heat transfer rate declines, the boiler components are exposed to overheating, which will result in metal fatigue and failure. Typically, this is seen in cracks, ruptures, or complete boiler failure cases. Leaving these items untreated can eventually result in boiler failures.

How to Address Boiler Leaks

If you notice that your boiler is leaking water, then you should call a service technician to further assess the situation and determine the best course of action to fix the issue. We offer 24/7 emergency services and can send a boiler technician to your business within 24 hours anywhere in the country. Additionally, we have provided both short- and long-term solutions.

Preventative Maintenance

The best thing you can do for your boiler system is to introduce preventative maintenance into your policies and procedures because it helps to troubleshoot any issues before it becomes a massive problem. We have created a boiler maintenance checklist of daily, monthly, periodic and annual services to help you get started. Another option is to connect with our partners at 801 Boiler and develop a comprehensive program using their Boiler Plus preventative maintenance services that will make sure your boilers get the service they need when they need it.


Once you identify the cause of your boiler leak, it is then important to understand the severity of the issue so you can determine if you need to implement a short-term or long-term solution. As you may have noticed some of the causes of water leaks might require a simple fix while others may be a significant overhaul to your boiler system. In the cases where the water leak was caused by the pump and pipes, you have the option to reseal or replace the part. This provides an immediate fix that should get your boiler up and running as soon as possible, or suggest that there’s a larger problem with your boiler system if it continues to leak water.

If you have a major leak or issue with your boiler system but can’t afford to shut down your operations, then contact Powerhouse about our rental boilers. We understand that you need a solution that solves for the short-term while you figure out the best course of action for the long-term. With our rental boilers, we provide you with rental equipment that will allow you to operate your business as normal while service technicians fix the issue on your original boiler system. We even include the option for you to be able to purchase our rental boilers should that be of interest to you and your team.


In some cases, the solution might be that you need to replace your entire boiler system. While that might not be an ideal scenario, a water leak caused by rust or corrosion might be a foreboding sign that your boiler is too old and will continue to malfunction despite any short-term repairs. If you need to replace your boiler system, please contact us and we will be able to help you determine the best equipment and services that meet your specific needs.

What’s the Difference Between a Residential and Industrial Boiler Leak?

The American Society of Mechanical Engineers (ASME) has developed the code (Boiler Pressure & Vessel Code, BPVC) with individual sections to cover all types of boilers and pressure vessels. Section I Boilers, Power Boilers, are high pressure boilers and are typically found in industrial and commercial settings while Section IV Boilers are low pressure and low temperature hot water boilers often found in small commercial and residential settings. Along with ASME guiding the manufacturing of boilers, the National Board has written a code, National Board Inspection Code (NBIC), to control the repair of boilers and pressure vessels.

It is important to understand the type of boiler that is being used in your facility and the issue at hand such as a boiler leak, so you can ensure that you are scheduling the appropriate service. For large apartment complexes, commercial and industrial companies, you will often have boiler systems that require a company with an “R” stamp for repairs. Meanwhile, residential boilers typically do not require a certified company to perform repairs and jobs may be handled by a trained plumber or technician. Powerhouse holds an ASME “S” Stamp and NBIC “R” Stamp, which certifies us for the manufacturing of new equipment as well as repair existing equipment.

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