Attachment 1 - SOW - Boiler Oxygen System.pdf

Building 753 Central Heat Plant Statement of Work

Upgrading the oxygen monitoring and control systems on the two Nebraska 85.4 mm MTBU/LBS steam boilers, serial numbers CP-4089 (boiler #1) and CP-4088(boiler#2) within the central heating plant. This involves the following detailed procedures:

1. Removal of Existing Oxygen Monitors: The existing oxygen monitors, including all associated wiring, sensors, and mounting hardware, will be carefully removed from both boilers. Proper lockout/tagout procedures will be followed to ensure the electrical supply to the monitors is de-energized before any work commences.

Removed components will be labeled and stored appropriately.

2. Installation of Replacement Controllers: The new oxygen control systems will be installed according to the manufacturer's specific instructions. This includes:

o Mounting the Controller Unit: Securely mounting the main controller unit in the designated location, ensuring proper ventilation and accessibility for future maintenance.

o Installing the Oxygen Sensor: Installing the new oxygen sensor probe in the appropriate location within the boiler flue gas path, following the manufacturer's recommendations for optimal placement and ensuring a proper seal to prevent flue gas leaks. This may involve welding or other specialized techniques.

o Wiring and Connections: Connecting all necessary wiring between the controller unit, the oxygen sensor, and the boiler control system. Wiring will be neatly routed and secured using appropriate cable ties and conduits. All connections will be verified for tightness and proper polarity.

3. Calibration to Manufacturer Specifications: After installation, the new oxygen controllers will be calibrated according to the manufacturer's detailed specifications. This will involve using calibrated gas mixtures and specialized equipment to ensure the accuracy and reliability of the oxygen readings. The calibration process will be documented, including the date, time, and results.

4. Optimization of Boiler Performance: The technicians will configure all available set-up options within the new controllers to optimize the performance of each boiler.

This may include adjusting parameters such as:

o Setpoint: The target oxygen level for combustion e iciency.

o Alarm Limits: High and low oxygen limits that trigger alarms to alert operators of potential issues.

o Control Algorithm: Selecting the appropriate control algorithm to regulate the air-to-fuel ratio based on the oxygen readings.

o Communication Settings: Configuring communication protocols for data logging and integration with the central building management system (BMS).

5. Comprehensive Testing: Following installation and configuration, the technicians will conduct a thorough test of all aspects of the new controllers to ensure the proper and safe operation of both boilers. This testing will include:

o Sensor Response: Verifying the accuracy and responsiveness of the oxygen sensor to changes in flue gas composition.

o Control Functionality: Confirming that the controller e ectively regulates the air-to-fuel ratio based on the oxygen readings.

o Alarm Functionality: Testing the functionality of all alarms, including high and low oxygen limits.

o Communication Functionality: Verifying communication between the controller and the BMS.

o Integration with Boiler Controls: Ensuring seamless integration with the existing boiler control system.

This comprehensive testing will be performed and documented before the 2025 heating season. This ensures that the new oxygen control systems are functioning correctly and contribute to the safe, e icient, and reliable operation of the central heating plant.

Additional Details:

Replacement oxygen probes are Land Genesis WDG-1210, one per boiler, and all corresponding materials needed to function.

BMS information: The operating system is a custom ACI program. Contractors can access the areas involved with the oxygen sensors and the combustion settings.

They utilize Semiens 350 controllers. Additionally, Johnson Controls has a Building automation controller as well, it does not interfere with the boiler operation.