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Fire Tube Boiler Compared to OAB

Is the One Atmosphere Boiler a Good Replacement for Your Fire Tube Boiler?

Fire Tube Boiler & OAB Comparison

  Fire Tube Boiler One Atmosphere Boiler
Equipment Costs Low/Moderate Low/Moderate
Installation Costs High Minimal
Output per $  
Upkeep/Maintenance Costs Moderate/High Low
Start Up Time Varies on particular unit and capacity. Expect a cold start up time of at least 15 minutes, with times ranging to over 30 minutes in some cases. OAB typically reaches temperature within 3-5 minutes of initial power.
Device Footprint Varies with output and temperature. Expect to utilize a minimum of 180ft^3 and a weight of over 300kg for a small unit. OAB volume starts at ~2.5ft^3 and a weight of approximately 30kg.
Maximum Operating Temperature Varies with pressure. The highest pressure fire tube boilers can reach temperatures of ~600°C. Typical fire tube boilers will generate steam at around 110-150°C. OAB units are available in temperatures up to 1300°C.
Plug and Play Operations No. If boiler is moved, it must be reinspected. Yes. The OAB can operate anywhere if given water and power.
Portability No. Installed into a fixed location. Yes. Small size and light weight allows for relatively high mobility.
Safety (Can it Explode?) Fire tube boilers can operate at pressures of over 10 atmospheres. The integrity of welds and construction materials are of utmost importance to ensure that they do not give way under such extreme pressures. One Atmosphere Boilers operate at one atmosphere of pressure. No pressurized boiler components are required, making operations significantly safer. If the OAB breaks, it will simply burn out and stop working, not explode.
Energy Efficiency Standard fire tube boilers typically approach an 80% conversion efficiency rate from input to output energy. With additional economizers and investments, this number can improve to 85-87%. OAB output energy efficiency is over 95% closer to 99% for standard operation./
Non-Productive Idling Time The majority of fire tube boilers do not produce on demand steam, meaning they need to be idled even when there isn't an immediate demand for steam. This can lead to a nearly 30% decrease in overall boiler efficiency. Powering down the OAB is feasible in many situations when there isn't a short term demand for steam. The OAB's rapid startup allows for easy on-lining of capacity.
Certifications Required Yes. All 50 states require boiler inspections for initial installations. No. Because the OAB doesn't have a high pressure vessel, it requires no special certifications.
Annual Inspections Yes. The majority of states require annual, bi-annual or quarterly boiler inspections. Non-compliant boilers will be immediately disabled. No. Wear and tear such as scaling and corrosion may occur in the OAB, but do not pose an immediate danger to safety, just device operation.
Extensive Operator Training Yes. Issues such as running the boiler dry pose a high risk to safety. A number of other incorrect operating procedures can lead to boiler damage and/or loss of life. No. Enclosed units require a water inlet, power source and directing the steam output.
Safety Training High. Proper operating procedures are vital to ensure safety. When improperly operated, high pressure boilers can be extremely dangerous. Moderate. OAB safety training primarily involves the risks of being burned by superheated steam and how to safely direct the steam output.
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750 Redna Terrace Cincinnati, OH 45215, USA
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