water line surging

3 Reasons Your Steam Boiler Water Line is Bouncing or Surging

We know boiler systems and their problems can be complicated. That’s why we’re explaining the familiar problem of water line surge. This article will help you identify 3 common causes so you can address them as quickly as possible.

What is surging and why is it so bad? Water surge is the dramatic change in the level of water in your boiler. You’ll know it’s happening because the water in the boiler’s gauge glass will appear to bounce up and down, reflecting the rapid increase and decrease of water. We say dramatic change because the water level will naturally change as the boiler is operating – this is totally normal. However, if your water line is bouncing more than an inch or so, you’ve got surge going on in there.

So why is water surge in a boiler so bad? For one thing, water surge is an indication of another problem in your heating system. The rest of this article will address those potential problems as the reasons why water surge occurs. Additionally, the rapid increase and decrease in your boiler water can trigger the water feeder to open or close unnecessarily. This will result in a flooded boiler. Water surge can also lead to inefficient boiler operation, which means poor heating or high fuel bills – or both. A properly maintained boiler system can save you a lot of time and money, as well as do its job of keeping you (or your residents) warm.

At Controlled Combustion, we see this problem pretty often. Here are the top 3 reasons, according to us, why your steam boiler water line is surging.

There’s something in the water

The reality is there’s always something in the water. But too much of anything can be bad for your boiler. Chemicals are one of the things that have the potential to mess with a boiler. While there might be different chemicals in the boiler water for different reasons, too much of some chemicals can cause the water’s pH level to rise. If your boiler water’s pH level is too high, it will result in foaming.

What is foaming? Foaming is what happens when water bubbles form on the surface of the water. Not only does this make the boiler water surge, but foaming also causes water to be thrown up into the system. Water in the system is bad for your boiler because it can lead to water hammer and other issues.

If foaming occurs in your boiler, check the pH level – it should be between 7 and 9.

But a high pH level is not the only thing that causes foaming. When your boiler water violently bounces, this is called priming. All that bouncing action can lead to foaming. What causes boiler water to prime? That leads us to our second reason why your steam boiler water line is bouncing or surging.

Dirt and oil

There are many places where dirt and oil cause problems and your boiler is no exception. It’s important to keep your boiler water clean since this will affect the steam that your boiler produces. If the water contains dirt or oil, steam will have a hard time traveling through the water and escaping its surface. As steam bubbles struggle to navigate through dirty water, they increase in size. These large steam bubbles cause the water line to bounce as they break through the surface of the dirt or oil filled water.

It’s necessary for manufacturers to use oil when they thread the boiler’s tappings; you will use oil to thread your boiler’s piping. So there’s no getting around the problem of oil in your boiler. Fortunately, your manufacturer will provide instructions on how to clean your boiler. Always follow the manufacturer’s instructions carefully. A regular maintenance program will also go a long way in preventing and addressing the accumulation of dirt and oil in your boiler.

Size matters

We’re talking about the size of your flame and your pipes. Let’s get into the flame first.

Remember, your boiler flame has a very important task: heat up a large amount of water at a very high temperature. It does so by first heating up the air as combustion gases inside the combustion chamber. The combustion chamber is a metal tube near the center of your boiler that is completely submerged in the boiler water. The heat of the combustion gases is transferred to the metal inside the boiler (the combustion chamber as well as a number of metal tubes also under water). In turn, the heat of the metal is transferred to the water inside the boiler. All of this heat transfer results in the steam you want to travel through your system and get where it needs to go.

If the flame is too big, or if it’s just too close to any part of the combustion chamber, you will run into problems. The flame is not supposed to touch, or impinge, on any surface. If the flame impinges it will cause incomplete combustion as well as uneven heating of the metal inside the boiler. Incomplete combustion will result in the accumulation of carbon, known as soot, inside the boiler. Soot can coat the inside of the metal tubes we mentioned earlier, which also have the job of heating up the water. The buildup of soot will retard the transfer of heat from these tubes.

So, what happens when we have uneven heating? The water will boil much quicker in the areas where there is more heat. When this happens, steam bubbles will rapidly break through the water’s surface in that area while the water level in the other areas (the areas not heating up as quickly) will drop.

You may not see all this action going on inside your boiler, but you’ll know it’s happening because your boiler water will surge. Double check that your flame is the right size and shape for your boiler to ensure the water boils evenly throughout.

Then there’s the pipes. All this steam that your boiler generates has to go somewhere, and, if all is well, it’ll go exactly where you need it to go. But if the pipes leaving the boiler are sized too small, problems will arise. Steam exits the boiler very quickly, so when it tries doing so through pipes that are smaller than they should be, it brings along boiler water with it. As the water is taken up with the fast-moving steam, it creates surging.

But surging is just one problem that undersized pipes cause; water hammer and uneven heating are among the others. Always follow the manufacturer’s instructions when piping your boiler; it will save you a lot of trouble down the line.

Don’t Wait to Address Water Line Surge

Here at Controlled Combustion, we’ve encountered all the problems that lead to a water line surge. In our experience, these are the 3 most common reasons why you may see your stream boiler’s water line bouncing around the gauge glass. So, the next time you notice this happening, try doing the following:

  1. Look for priming or foaming – this could mean that your water has either dirt or oil in it, or the pH of the water is too high. If the water seems fine,
  2. Check your flame – make sure it’s not too close to or too big for the combustion chamber. If the flame doesn’t seem to be the problem, then
  3. Make sure the pipes leaving the boiler are the proper size, according to your manufacturer’s suggestion.

If you’re not sure how to perform any of these checks, or you did perform them and you still haven’t found the problem, don’t hesitate to contact a boiler service company. Hesitating to address any boiler problem increases your risk of running into bigger, more expensive problems.

When it comes to boiler maintenance, it’s crucial to work with a heating contractor that understands the entire heating system. Controlled Combustion specializes in all areas of your steam heating system and hydronic heating system. Our range of services fall into five categories: 1. Compliance; 2. Maintenance; 3. Service; 4. Replacements; 5. Upgrades. We provide these services to the entire New York City area as well as Bergen County, Rockland County, Westchester, and Yonkers. Controlled Combustion’s trustworthy Emergency Boiler Service is available 24 hours a day, 7 days a week, 356 days a year. Call us today to find out how we can help you run an efficient heating system.

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