Laying up your steam boiler or heating boiler can help prevent corrosion and scale. This is done in addition to the normal chemical treatment program. Additionally, even the best chemical treatment program must be supplemented during the non-operating, or lay-up cycle to prevent corrosion. When your boiler is taken off-line and allowed to cool down, special chemicals must be added at much higher levels to offset the increased level of available oxygen. This is important because oxygen can quickly produce pitting in both boiler tubes and tube sheets. Furthermore, once a pit develops it can corrode completely through a tube in a matter of days, and require costly repairs.
Updated March 24, 2022
Determine how Long the Boiler will be Shutdown
Choose a wet or dry layup based on the length of time that you intend the boiler to be shutdown.
Short Term (5-10 days)
Use wet layup
Medium Term (10-30 days)
Use wet layup
Long Term (30+ days)
Use dry layup
Our expert service technicians perform wet and dry layups for any length of time. To get help from an expert click here to message us
Wet and Dry Layup Procedures
Wet Layup
Fill the boiler with water that is 180°F or hotter to drive off dissolved oxygen
Add the recommended treatment chemicals until the alkalinity of the boiler water is at or above 400 ppm and the sulfite is above 200ppm
Button-up all inspection ports, fill the boiler to the top of the steam header, while vented. Then, seal the header
Circulate water a couple of times a month, allowing the chemicals to blend to treat all surfaces
Test the system water regularly and add additional chemicals as needed
Dry Layup
Blowdown the boiler before draining
Open a vent. Once the water temperature is less than 140°F and the boiler is at 0 psi, drain the boiler and allow it to dry thoroughly
Open and clean the fireside. Keep the boiler warm as the melted, wet soot will be much easier to remove than the cooled, dry soot
Dry the fireside with a heater or fan
Open and clean the waterside. Close the gate valves near the vessel and keep the manhole top open
Examine internal and external surfaces. Inspect for leaking and cracking. Swab the fireside with neutral mineral oil for corrosion prevention
Consider further protection can be achieved through the use of desiccants, sorbents, or our recommended Boiler Lizard®
To talk to an expert about boiler layup or other technical matters, call one of our Technical Support Team Members at 800-848-9526 or click here to message us
Matt Welsh
Matt Welsh is the Vice President and Water Consultant at Chardon Labs. He helps consult a wide range of customers utilizing various methods of water treatment, from chemical to chemical-free approaches, large and small applications, and across a wide range of geographical influences. With 20 years of water treatment experience, including a wide range of troubleshooting and service in potable water and non-potable HVAC and industrial applications, he is an expert in water treatment chemistry for cooling towers, boilers, and closed-loop systems.