Boiler Blog | Nationwide Boiler Inc.

Improper water treatment is the leading cause of tube damage and poor performance in a boiler system. In this month’s edition of Boiler Basics 101, we will discuss the consequences of introducing your boiler to hard water and the importance of utilizing a water softener.

If water is not treated properly before entering the boiler, scale will begin to form due to a chemical imbalance within the tubes. Scale is defined as concentrated minerals being precipitated when the water is evaporating in a boiler. The precipitated minerals consist of a mixture of calcium, magnesium, iron, aluminum, and silica, and are often referred to as “hard minerals”. Scale is detrimental in a boiler system because it acts as an insulator and prevents proper heat transfer. This can lead to decreased boiler efficiency, costly downtime, and even premature boiler failure. Eventually, scale build-up will cause boiler tubes to overheat and rupture.

To help prevent scale and deposit formation, make-up water should be circulated through a water softener before it is fed to the boiler. A water softener is an ion exchanger designed to remove positively charged ions from hard minerals (like magnesium, calcium, and iron) and replace them with negatively charged ions. The resin beads that are inside the resin tank are negatively charged by brine, which contains salt and potassium. As the water goes through the resin tank, the positively charged ions are chemically attracted to the negatively charged resin beads. The hard minerals then stick to the resin as the water runs through the tank, thus turning the water into “soft water”. This process frees the water from these minerals before entering the boiler and decreases the risk of tube scaling and irreversible damage.

Water softening is one of the main ways to increase boiler longevity and maintain boiler performance. Nationwide Boiler’s fleet of mobile boiler rooms, steam plants, and feedwater system trailers include duplex water softening systems to ensure optimum boiler performance. We also have skid-mounted and trailer-enclosed, stand-alone water softeners available for rent or for purchase. It’s important to know that when Nationwide Boiler delivers a rental unit, it is the customer’s responsibility to maintain and supervise the water treatment and chemistry of the water entering their rental boiler.

All boilers are subject to damage if proper water treatment procedures are not followed. This is an important consideration both during operation and when the boiler is idle. To avoid damage and costly repairs, monitor water chemistry routinely and ensure that you are supplying your boiler with soft water at all times.

Winter is officially here! When cold weather settles in, it is important to make sure that your boiler is well-maintained. Like any other mechanical system, boilers will tend to wear down over time. Boilers can be dangerous if not properly inspected and not working properly. Full boiler efficiency will help avoid boiler downtime and unnecessary expenses. Here are 14 steps to follow to help you get on track with your winter maintenance:

1. Inspect the fuel source.

The fuel used needs to have the proper viscosity for atomization. Test and gauge the fuel viscosity to ensure full efficiency. 

2. Inspect the fireside.

Inspect the fireside and look for any indication of corrosion.  If no corrosion is found, continue to clean the fireside and the furnace area as necessary. 

3. Check the refractory.

Due to the cooler weather, be aware of thermal expansion. Boiler refractors are designed to expand and contract with temperature changes. But all boilers will incur some cracking due to those constant changes. If excessive cracks are found, repair as needed.

4. Inspect the waterside.

Inspect the waterside of the boiler for scale and remove as necessary. Scale prevents heat transfer inside the boiler and can significantly lower efficiency. All water-level controls need to be properly inspected, opened, and cleaned.

5. Inspect the burner.

While the boiler is open, inspect the burner components.  Visually check the boiler’s flames. If there are inconsistencies in the flame patterns or color, there may be an underlying issue. Make sure everything is in order before proceeding. Failure to maintain the fuel system in good working order could result in excessive fuel costs, loss of heat transfer or even a boiler explosion.

6. Inspect the controls.

Any controls used to monitor the water level of the boiler should be checked after reinstalling onto the boiler. Before starting the boiler, inspect all the operating controls and look out for any signs that show of overheating.

7. Close all openings.

Make sure all of the boiler’s openings which include all doors, manholes and handholes are properly closed.

8. Open the boiler’s valves.

This is inclusive of the boiler’s header valves, piping drains and vent valve. Make sure all are operating as required and that the vent is not clogged. All ventilation requirements for the boiler need to be checked and met. 

9. Test the pumps and valves.

You will need to test all of the boiler’s pumps and valves before fully operating to make sure everything is working properly. Once everything has been tested and approved for operation you can start warming up your boiler.

10. Warm up your boiler.

To account for the colder weather it is important to increase the boiler pressure slowly. This allows the joints and metals to heat up evenly and reduce expansion stress. 

11. Switch to automatic operation.

Once your boiler is up to operating pressure, switch to automatic operation.   

12. Analyze combustion.

When you perform a combustion analysis this helps increase performance, verify component operation, decreases maintenance and fuel requirements. This will save some potential expenses made in operation. 

13. Water treatment.

Water treatment is needed before feedwater can be pumped into a boiler. Test the boiler water and treat accordingly. Follow the guidelines provided in the Installation and Operations Manual.

14. Monitor your boiler. 

Within the first few days after start-up, monitor the boiler for any leaks or any additional maintenance items. If you discover water or steam leaks at this point, shut the boiler down and have the leaks repaired.

As we enter the heart of the winter season, it’s important to remember that cold weather conditions have the potential to cause freeze damage to any boiler installed outdoors. In particular, the protection of non-enclosed rental boilers and equipment installed outdoors is imperative to avoid damage. Rental boilers and equipment come in various designs and configurations, and each unique type will require different forms of freeze damage protection. Knowing the type of equipment will help determine the right steps on how to prevent damage.  

 Here are the most common types of rental boilers: 

  _{- Mobile Boiler Rooms
  - Mobile Steam Plants
  - Trailer-Mounted Boilers
  - Skid-Mounted Boilers
  - Mobile Feedwater Systems
  - Skid-Mounted Deaerators and Other Auxiliary Equipment}

Just remember that any lines without a constant flow of water will freeze and must be properly protected from the cold. Always make sound engineering judgment calls to avoid the repercussions of freeze damage. If you have a temporary boiler and want to learn more about the proper ways to avoid freeze damage, read the recent issue of Process Heating. Nationwide Boiler was featured and our Marketing Manager, Chelsey Ryker goes over the specifics of boiler protection for each model.

With air emission regulations constantly changing, Nationwide Boiler has had to adopt new ways to keep up with more stringent standards. For instance, in 1995, Nationwide became the first rental boiler company to convert their fleet of watertube boilers to low NOx levels of 30 ppm. The company’s method of choice to reduce NOx emissions further led to the creation of the CataStak™, which was developed in the late 90s and since then has proven to reduce NOx emissions by as much as 99%. In addition, it can be supplied for new equipment or as a retrofit on an existing system. What were the early days of the CataStak like? What steps did it take to get to where it is now? Let’s find out in this edition of Boiler Basics 101.

It all began when Nationwide Boiler chose Selective Catalytic Reduction, or SCR technology, to be their solution to NOx compliance. They determined that SCR was the best alternative due to its reliability, ease of operation, high efficiency, and its ability to reduce emissions to single digit NOx levels. In 1999, Nationwide Boiler became the first rental boiler company to conduct an SCR field demonstration on a package watertube boiler and followed by utilizing the system heavily in their rental fleet. The enormous success of rental SCR systems suggested to company management that a market existed for a field-retrofit system for package boilers - later to be branded and trademarked in 2001 as the CataStak™ SCR System.

Fast forward to the year 2004, Nationwide began offering the CataStak for new and existing package watertube boilers to meet sub 9 ppm NOx levels. After witnessing its continual growth, Nationwide Boiler introduced a new business unit, Nationwide Environmental Solutions (NES). NES was formed with a focus on lowering overall industrial greenhouse gas emissions and increasing the operational efficiency of fired equipment. This allowed Nationwide to continually raise the bar in providing reliable solutions to meet market demand.

Nationwide later developed the urea-based CataStak as a solution for customers adverse to the stringent handling requirements of ammonia. The system utilizes common diesel exhaust fluid (DEF), a safe and readily available 32.5% liquid urea solution. It was first demonstrated on a package firetube boiler in 2011 and has since been expanded to be utilized on watertube boilers and other fired equipment. Initially, the system was offered only for permanent applications but in 2018, Nationwide became the first rental boiler supplier to provide urea-based SCR systems on a boiler rental project. The company now has a fleet of urea-based SCR systems to support the rental market.

The CataStak has come a long way and has now been installed in over 180 applications. These installations range from temporary to permanent package boilers, fired heaters, gas turbines, and heat recovery steam generators. With all of these accomplishments, the CataStak has become the standard for compliance assurance, reliability and product quality. CataStak SCR systems lead the industry with the best track record in terms of performance, and source test results often exceed current local, regional and national emissions requirements.

If you’re interested in learning more about the CataStak, our website has all the details you need to get started. And be sure to check out the previous and future Boiler Basics 101 blogs to continue learning about various boiler-related topics.