Natural disasters like hurricanes, floods, and winter storms can wreak havoc on facilities. One of the most critical systems affected? Your boiler. Getting it back online is not as easy as just restarting it. There are a lot of things to take into consideration when getting your boiler back up and running. Here's how to bring your boiler system back online safely and how WARE can help before, during, and after disaster strikes.
Why Boilers Shut Down During Disasters
Boilers are equipped with safety interlocks designed to shut systems down when unsafe conditions are detected. Some common causes:
Low or High Water Conditions
- Low water can warp or crack your pressure vessel. Have it inspected before restarting.
- High water could indicate failed controls or sensor issues.
Fuel Flow Disruptions
- Sudden changes in fuel supply from the utility or within your gas/oil train can trigger shutdowns.
- Inspect pressure regulators, valves, and fuel filters for failure.
Low Air Supply
- Lack of air means poor combustion and insufficient draft.
- Check filters, fan systems, and damper positions.
High Stack Temperatures
- Caused by poor heat transfer, incomplete combustion, excess air, or burner misalignment.
- Check for soot buildup, scaling, or control system malfunctions.
Let's dive deeper into each of these.
LOW OR HIGH WATER
If your boiler is running with too little water, that can cause heat stress that can warp or crack the pressure vessel and lead to failure down the line. So if low water is detected, the boiler will shut down to preserve its integrity. If a low-water switch has triggered the shutdown, you need to determine exactly why it was triggered. Was it just a matter of not supplying enough makeup water? Or is there something more substantial going on, like a leak in the water supply or a crack that’s venting steam? If a low-water shutdown occurs, it’s best to have the boiler evaluated by a professional from WARE to make sure there was no damage to the components or pressure vessel. Low water can be a very serious situation that can cause extensive damage to your boiler’s internals, and even require full replacement of the pressure vessel. So let the professionals handle it.
If the shutdown was caused by high water, that also needs to be addressed so the problem doesn’t continue. If the system added too much makeup water, there may be a problem with the control system or with a water sensor. Once again, if there’s any question as to why the boiler had too much water, a professional from WARE can diagnose and fix the problem right away. Because if a problem in the water supply isn’t fixed, the boiler will just keep shutting down after restart until the root cause is addressed.
FUEL VARIATION
If your boiler is receiving too little or too much fuel, that can trigger a shutdown. These safety systems are in place to make sure your boiler isn’t running too rich or too lean. If it’s running too lean, that can cause uneven heating that leads to heat stress. If the boiler is running too rich, that can lead to sooting, which can clog or obstruct burners and lead to inefficient operation and heat stress. If a fuel-related shutdown occurs, the first thing you have to determine is why the variation occurred. If it’s simply a matter of the utility company having problems, the boiler should operate normally once the regular fuel supply is restored. However, if the problem lies within your gas train – perhaps a malfunctioning pressure regulator or a failed valve – it’s best to have an expert from WARE check it out and repair the problem to get your boiler back online safely.
LOW AIR
If your boiler isn’t getting enough air, it’s going to burn inefficiently, and it’s not going to generate the draft needed to carry exhaust gases to the stack. Low air can be caused by something simple, like a filter obstruction. However, it can also be an indicator of misaligned or malfunctioning dampers. That’s when a professional from WARE should get involved, because they can get your control system, modulating motors, and linkages back to factory spec to help your boiler run properly.
STACK TEMPERATURES
Your boiler may have safety systems in place that will trigger a shutdown if stack temperatures fall outside of the manufacturer’s recommended specifications. That’s because high stack temperatures are an indicator that heat from the fireside isn’t being transferred to the water side as intended. Maybe it’s as simple as an obstruction in the stack. But high stack temperatures can also be an indicator of other issues, as well.
- INCOMPLETE COMBUSTION can be caused by something affecting the fuel air mixture. When this happens, soot can start to build on the fire side and essentially insulate the fire side, which will reduce proper heat transfer.
- SCALING causes high stack temperatures because it prevents all the heat from being transferred to the pressure vessel. If that heat isn’t transferred, it has to go somewhere, and that somewhere is “out the stack”. If you have scaling, that needs to be addressed right away because you’re not only causing heat stress to your pressure vessel, you’re also wasting fuel.
- EXCESS AIR causes high stack temperatures because it creates too much draft which, in turn, pulls heat away from the pressure vessel and out the stack.
- DAMAGED OR MISALIGNED BURNERS can direct heat away from where it’s supposed to go, causing that heat to be carried up the stack by the draft and raise stack temperatures.
What to Inspect Before Restarting Your Boiler
Use this inspection list before attempting to restart:
- Pressure Vessel: Look for leaks, cracks, warping
- Burners: Confirm correct alignment and no obstructions
- Gas or Oil Train: Check valves, regulators, strainersAir Systems: Inspect fans, dampers, pressure switches
- Control Panel: Verify wiring is dry, sensors are activeFlame Safeguards: Confirm signal strength and sensor cleanliness
- Water Treatment: Ensure chemistry and feedwater are within spec
- Exhaust Stack: Look for soot, corrosion, or physical damage
If anything seems off, call WARE before restarting.
When to Call for Boiler Service
When the boiler restarts after an emergency shutdown, it’s important to make sure it’s operating normally. That means listening for any new noises or vibrations that could indicate a change in your boiler’s integrity. If you think something’s different, get a professional from WARE to check it out. It’s always better to be safe than steamless.
If you have an emergency shutdown occur and you can’t immediately verify the cause, or if you suspect you may be dealing with an overheated boiler or damaged or misaligned burners, WARE is always here to help. Our highly trained technicians can be dispatched right away to get you back online safely. Remember, if there’s ANY QUESTION AT ALL as to why your boiler shut down, don’t make assumptions. Preserve your equipment life and your safety by letting a professional from WARE determine the how, what, and why.
Request Emergency Boiler Service
If you’d like to learn more about how your boiler operates so you can better understand why shutdowns occur, consider taking a class from WARE’s Boiler University. If you have a shutdown occur, or if you just want to make sure your boiler is running at top efficiency, we’re always here to help.
FAQ
What should I inspect before restarting a boiler after a flood?
Check the pressure vessel, controls, fuel trains, air supply, and burner alignment for damage or contamination.
Can I restart a boiler without a technician?
Only if you’re fully confident in its condition. If there’s any uncertainty, call WARE.
Why is my boiler stack temperature too high after restart?
This could indicate scaling, soot, excess air, or poor combustion — all issues that require service.
Does WARE offer emergency boiler rentals?
Yes. We can deliver rental boilers fast, 24/7, anywhere in the U.S.
We’re Here Before, During, and After the Storm
Need help now? WARE’s expert boiler technicians are ready to get your system back online safely and efficiently.