Boiler maintenance saves heat system owners the cost and hassle of constantly replacing burned-out boilers that shut down. For more information, please refer to a blog we posted on The Boilerman last year titled Boiler Maintenance Checklist. Repairing its refractory, when necessary, is also vital to proper boiler maintenance.
Castable, Refractories & Insulations from Hurst Boiler are available from Engineered Energy Equipment:
Hurst Hybrid Mud, Castable 1800 & 2800 Degree, Furnace Crete, Coreline, One Shot, Mineral Wool, Kaowool, Mill Board, Rock Wool, Blankets, Fire Brick, Refractory Hangers, Stainless Steel
What is boiler refractory repair? What is the purpose of refractory material?
An article on the website for Power Mechanical, a boiler rental service and seller, reports, “Boiler refractory is heat-resistant material that lines the high-temperature areas of the furnace.” The water in a boiler acts as thermal protection for the heating surface. Areas that are not protected by the water wall are protected by refractory. The Power Mechanical article Understanding Boiler Refractory explains, “The refractory around the burner head actually protects the flame from being cooled too rapidly (from heat transfer) along with creating the proper flame shape and velocity.”
Types of Boiler Refractory
A webpage on the website for Marine Insight, an online maritime training and educational platform, lists the materials that make up refractory as:
- Acid materials include clay, silica, quartz, sandstone, and gamister.
- Neutral material which consists of chromite, graphite, plumbago, and alumina.
- Alkaline or Base material consists of lime, magnesia, and zirconia.
Different Types of Refractory Materials, the informational page on Marine Insight mentioned above also describes the two available refractory materials. Refractory comes in firebricks and monolithic refractory, divided into three categories: moldable, castable, and plastic chrome core.
Boiler Refractory Repair Procedure
Cracks in the refractory often cause boilers to function less efficiently and break down. A blog titled The Importance of Refractory in a Boiler from Premier Controlled Combustion NYC Company, a New York-based commercial heating company, reports three things that can cause refractory material failure.
- Improper material selection when choosing refractory material.
- Poor installation of the burner refractory material.
- Incorrect storage of refractory materials before installation or improper mixing of the refractory materials.
If you detect a crack in the refractory smaller than your fist during a routine burner inspection, there is a way to repair it on your own. First, a blog post from WARE, an industrial and commercial boiler rental and service company, reminds readers, “Any cracks 1/8 of an inch or less are heat cracks and do not need to be patched.” Cracks larger than heat cracks can be repaired by following the steps WARE’s blog post lays out.
- “V out” cracks by cleaning out loose materials.
- Using a spray bottle, dampen Ram 90 and the area to be patched.
- Work Ram 90 into the cracks and smooth it out.
Please note that Ram 90 is a specific refractory mix. We want to reiterate the incredible importance of knowing exactly what material makes your burner refractory. Often, a heating professional can answer this question. WARE also warns, “If the crack/hole is bigger than your fist, call a professional. Because it’s very hard to get right.” If you own a heating system and live or work in Central Florida, please call Engineered Energy Equipment if you detect a large crack in the refractory.
References
- https://eeeinc.net/blog/
- https://eeeinc.net/2023/09/boiler-maintenance-checklist/
- https://www.powermechanical.com/
- https://www.powermechanical.com/understanding-boiler-refractory/
- https://www.marineinsight.com/
- https://www.marineinsight.com/tech/boiler/different-types-of-refractory-materials-used-in-boilers/
- https://heatingny.com/2021/05/03/the-importance-of-refractory-in-a-boiler/
- https://heatingny.com/
- https://www.wareinc.com/
- https://www.wareinc.com/helpful-resources/blog/how-to-repair-your-boiler-refractory-after-it-gets-shocked-and-when-to-call-a-professional
- https://eeeinc.net/
