TYPICAL SPECIFICATION
ECO*PAK MBSTM - Ultra-Efficient Boiler Plant
GENERAL DESCRIPTION
Furnish and install an Armstrong ECO*PAK MBS™ Model______Ultra-Efficient Boiler Plant as part of the building hot water heating system. The ECO*PAK MBS™ shall provide the building heating load requirement with design day heating water over a design envelope defined by a maximum and minimum design day capacity and delta T ranges and meet the specified turndown ratios.
The ECO*PAK MBS™ shall be a factory pre-assembled and pre-tested modular packaged system which comprise of a series of interconnecting boilers, pump and control modules which will contain all of the sub-systems required to provide primary and distribution Low Temperature Hot Water (LTHW) to the building at seasonal efficiencies of up to 98%. The system provides the benefit of a single source of responsibility for design and performance of the components as an integrated system.
The modules, which are 30 inches wide maximum, are easy to maneuver and can be transported through narrow access single doors. On site, minimal work is required to the ECO*PAK MBS™ before it will be up and running for space comfort heating; only 1 gas pipe connection, building supply and return water piping, cold water supply for make-up, exhaust flues as well as electrical power to the integrated control panel are required on site. Building Automation System (BAS) serial interface connections would be required as well.
The integrated controller shall be factory tested with all control sequences and alarms simulated. The entire system shall be hydrostatically tested in the factory and performance testing shall be done as a complete system to confirm the equipment performance prior to shipping. All hot water pipe-work of the MBS shall be insulated. Site commissioning of the ECO*PAK MBS™ assembly shall be done via the user-friendly Human Machine Interface (HMI) for easy parameter setup and start-up.
PRODUCTS
The ECO*PAK MBS™ shall include hot water pumps, condensing boilers, integrated controller with temperature sensors & serial communication to BAS, expansion tank, air separator, isolating valves, strainer, chemical pot feeder, make-up water system, and interconnecting piping with air vents, drain cocks and test points. As an option the ECO ECO*PAK MBS™ shall be supplied with gas meter and hot water flow sensor.
Armstrong intelligent Twin-head pump for duty/standby operation incorporates Armstrong’s motor-mounted variable frequency drives (VFD’s) which will constantly adapt to changes in the distribution system characteristics. It features economical inside-type, single-spring mechanical seal, serviced by removing the rotating assembly while the pump casing remains in the line. Dynamically balanced impeller assures smooth, vibration-free operation. Radially split volute with equal suction and discharge flange sizes. Separate tapped openings for gauge, flush and drain connections.
Fully modulating low NOx gas fired condensing boilers with stainless steel heat exchanger. The boilers shall bear ASME and National Board stamps. The boilers shall also be certified for use on Natural Gas and LPG and shall comply with the energy efficiency requirements of the latest edition of the ASHRAE 90.1 Standard and the minimum efficiency requirements of the latest edition of the ASHRAE 103 Standard. The boiler shall meet as a minimum U.S. Environmental Protection Agency and Department of Energy guidelines for “Energy Star” efficiency.
The integrated controller shall:
1. Ensure minimum hot water flow rates are maintained to operate in the high efficient condensing mode at all times within a variable primary flow configuration
2. Optimize boiler firing rate to match exact heating loads
3. Optimize boiler sequencing to achieve the highest efficiency possible from the system
The integrated controller shall have a NEMA 1 enclosure and house PLC’s, circuit breaker, terminal strip and main disconnect switch. The controller shall incorporate a door mounted 5.7" touch-screen HMI for all necessary user interface functions. The integrated controller shall be pre-programmed with project specific data for easy start-up and commissioning. On start-up a read only screen shall display Outdoor Air (OA) temperature, HWS temperature, HWR temperature, system hot water ∆T, system heat output in MBH (optional), and pump kW usage. The initial screen shall also display boiler(s) status, pump status, and system status. System run time and individual pump hours run shall also be displayed. Alarms, data trending of system parameters shall also be displayed on the touch-screen HMI and logged in the memory of the HIM available for upload when required.
A second screen (which is password protected for field adjustable parameters) shall provide access to input time, night setback and holiday settings and virtual hand/off/auto (HOA) and time extension buttons. Subsequent screens shall be password protected and shall give access to mode/system set-up, PID set-up, frost protection, clock set-up and reset and restore default screen.
The logic controller shall be based on Flash style memory; older style EEPROM style memory shall not be acceptable. Keypad based interfaces, LCD readouts and LED displays shall not be accepted. The integrated controller shall perform online self-diagnostic testing of the CPU(s), RAM and flash memory. No data shall be lost during power supply interruptions.
The ECO*PAK MBS™ integrated controller shall be capable of both hard-wired and serial communication with the BAS. The standard communication protocol is Modbus. Optional communication protocols include BACnet IP, BACnet Ethernet, BACnet MS/TP and LonWorks. Clearly marked terminals shall be provided for BAS interface and for various field-mounted devices such as OA sensor. A hot water flow sensor can also be supplied as an option which when connected to the terminal strip would display water flow reading in GPM on the HMI.
A make-up cold water fill assembly shall be incorporated to automatically fill the entire system to the pre-set cold fill pressure. An expansion tank with heavy duty butyl replaceable bladder shall be provided loose for connection to the return header with isolating valve.
An optional in-line, turbine type gas flow meter shall be fitted in the gas header in order to read gas consumption and monitor thermal efficiency. When the gas meter is connected to the controller terminal strip would display gas consumption reading in SCF on the HMI. Safety valves shall be fitted to each boiler supply pipe and a plugged gas purge valve shall be fitted to the end of the gas header.
The ECO*PAK MBS™ system shall be commissioned by an approved Armstrong Service Partner and shall be provided with a comprehensive technical manual that includes technical information as well as installation, commissioning and servicing instructions. Commissioning shall include final checkout, adjustment and start-up. On-site operator training session on the operation and maintenance of the MBS shall also be provided.
QUALITY ASSURANCE
The manufacturer shall have a minimum of 25 years manufacturing and application experience and shall be responsible for the proper pressure and flow in the entire system. The packaged system manufacturer must hold an ISO 9000 and 14001QA certification, or approved equal.
Acceptable manufacturers include Armstrong, or approved equal. Equal and alternate manufacturers must submit a request to bid in writing to the owner, or owner’s consultant prior to tender closing. Alternate bids must be entered with savings over base bid. The manufacturer must provide the following information for consideration prior to entering a bid:
1. Energy performance
2. Equipment selection data
3. Control sequence of operation
4. List of similar installations with references
5. List of deviations to the specification