Nonresidential Steam Trap Monitoring

Measure Description

The proposed code change is designed to reduce energy waste from industrial steam systems by minimizing the time between steam trap failure and replacement, and by increasing the longevity of steam traps. The two specific recommendations are:

1. Automatic Steam System Fault Detection and Diagnostics (FDD). Steam systems would be required to have central FDD monitoring systems that detect when a steam trap fails and report that information to the facility operator or facility maintenance staff. The central FDD monitoring system must report the status of each steam trap no less than once every eight hours. If a steam trap fails, the central FDD system must be capable of automatically generating an alarm that indicates which steam trap has failed. The proposed code change would also require that each steam trap have fault detection sensors that are capable of communication with the central FDD monitoring system. This code requirement would add a new acceptance test to verify that the central FDD monitoring system is installed and operating according to code requirements. Typical steam system maintenance includes annual inspection of all steam traps. It is possible that some steam traps fail soon after annual inspection and are not replaced for nearly a year. During this time, traps that fail open leak steam into the condensate return system. By adding a steam trap FDD system, the plant operators are alerted soon after steam trap fails and can organize a replacement.
2. Steam Trap Strainer and Blow-off Valve Assembly. Each steam trap in the steam system would be required to be protected with a strainer and blow-off valve assembly. This could be accomplished by either using steam traps with integral strainer and blow-off valve assemblies or designing the steam system so that each steam trap would be installed within three feet downstream of a strainer and blow-off valve assembly. Strainers protect the steam trap from debris, prevent clogging from contaminants, and prevent the valve inside to the steam trap from closing. Steam traps without strainers fail more frequently and leak more steam.

The Statewide CASE Team considered several options to apply the requirements to steam systems in California. Each option described below and in Section 3.2.4 would allow the state to realize the energy and GHG savings along different time horizons:

• Option A: Under this option, the proposed requirements would only apply to new industrial facilities[1] or new processes added to existing facilities.
• Option B: Under this option the proposed requirements would apply to the systems identified in Option A (new facilities or lines) and the portions of existing steam systems that are served by equipment that is replaced at the end of life.
• Option C: Under this option, the proposed requirements would apply to all replacement steam traps.

The Statewide CASE Team recommends that the Energy Commission adopt Option C and apply the proposed requirements to all steam systems that meet the cost-effectiveness threshold. Doing so will result in significant natural gas savings and GHG reductions. Under Option A, the state may never achieve the full potential energy and GHG savings as the requirement will only apply to new process operations. Existing facilities would be exempt. Under Option C, the full savings potential could be achieved in four to five years.

Although the Statewide CASE Team recommends that the Energy Commission implement Option C for Title 24, Part 6 based on cost effectiveness and energy savings, the Energy Commission has indicated a preference for a proposal that applies requirements only to new facilities and new process lines (Option A, which is the smallest scope) for the 2022 Title 24, Part 6 Standards. This report therefore describes applying the requirements in accordance with Option A for Title 24, Part 6 and recommends developing requirements for CALGreen that would apply recommendations more broadly, if the measures were adopted by jurisdictions through Reach Codes.

The proposed Title 24, Part 6 changes would be mandatory and would add a new subsection to Section 120.6 of Title 24, Part 6. The requirements would apply to newly constructed process facilities and new production lines within existing facilities. It would only apply to steam systems that have greater than 15 pounds per square inch gauge (psig) of connected steam line pressure and a connected boiler capacity greater than 5.0 million British thermal units per hour (MMBtu/hr).

The two-tiered recommendations for CALGreen would require steam trap FDD and steam trap strainers on steam systems that undergo major equipment replacements (Tier 1, consistent with Option B) and all steam trap replacements (Tier 2, consistent with Option C). As with the Title 24, Part 6 proposal, the CALGreen requirements would only apply to systems with a connected steam pressure greater than 15 psig and a connected boiler capacity of 5MMBtu or greater.

Neither Title 24, Part 6 nor Title 24, Part 11 currently regulate the installation of steam traps or require the installation of a strainer with a blow-off valve. The proposed code change represents additions to Title 24, Part 6 and Title 24, Part 11 where none previously existed.

[1] Section 100.1(b) of Title 24, Part 6 includes the following definition as one of the nonresidential building occupancy types “Industrial/Manufacturing Facility Building is a building with building floor area used for performing a craft, assembly or manufacturing operation.

Relevant Documents

Measure proposals, supporting documents, and other outside references will be made public as they become available.

• CASE Study Final Report – Nonresidential Steam Trap Monitoring
• Final CASE Report – Nonresidential Steam Trap Monitoring
• Draft CASE Report – Nonresidential Steam Trap Monitoring
• Covered Processes Part 2 Submeasure Summary
• Presentation – Nov 7th – Covered Processes Part 2
• Notes – Nov 7th – Covered Processes Part 2