Section 15010, Mechanical Provisions (1) Related Documents

(11) Pipeline Strainers:

A. Y-type strainers with stainless steel screen with 0.045 inch perforations. Manufacturers: Armstrong, Crane, Sarco

B. Provide drain with ball valve and hose connection and cap on all strainers.

(12) Air Vents:

A. Automatic Air Vents: Provide air vents designed for 75 psig minimum operating pressure and 230 F maximum operating temperature. Vents to be float type with integral air relief port and built in or separate shut off valve. Manufacturers: Spriovent, Armstrong Model 11-AV or approved equal.

B. Manual Air Vents: Not used. Provide valve with nipple and cap on plug where venting is required.

C. High-Capacity Air Vents – Automatic: Float type vent with integral shutoff valve for service. Rated 150 PSIG, 250 Fahrenheit. ITT Bell and Gossett Model 107A or as noted on drawings.

(13) Pressure Gauges:

A. Provide pressure gauges of the range required for the system installed where shown.

B. Gauges: 4 ½” dial, adjustable pointer, movement bushed with parts of dissimilar metal to reduce were. Bourdon type stainless steel or brass tube and socket. Case is black finished aluminum with blowout grommet and acrylic window. ¼” NPT lower process connection. Accuracy per ASNI Standard B40.1 Grade 1A of plus of minus 1% of full scale. Manufacturers: U.S. Gauge Model 4801, Ashcroft Model 1009, Marsh 5000, Tel-Tru Model 52B series, or approved equal.

C. Provide Anderson Greenwood gauge valve Model M931, ½” NPT connections and integral needle type bleed valve, at all gauges.

(14) Pressure Relief Valve:

A. Diaphragm-operated, bronze body, ASME Section IV, minimum size 1.5 inches. Relief pressure as noted on the drawings.

(15) Expansion Loop:

A. No thrust load, ASME B31.1, Flexicraft Metraloop piping expansion loops, or approved equal. Material to match piping, provide full size of pipe.

(16) Execution:

A. General

1. Coordinate and work directly with the Testing and Balancing Agency to provide all systems in proper operating order. Make corrections and adjustments as required.

2. Thoroughly clean the exterior of all apparatus and equipment at the completion of the work, and touch-up paint as required on all finished surfaces.

B. Pipe and Fittings

1. Support piping per Section 15050. Route piping so as to avoid air entrapment at sections which cannot be vented. Provide all valves, connectors, unions and controls show on drawings or as required to provide competent isolation for service.

2. Typical Piping

a. Close all openings in pipes with appropriate caps, plugs, and covers during storage and progress of the work to preclude introduction of contaminants.

b. Slope all pipelines and provide low point drains for all piping and equipment.

c. Provide nipples minimum 2 pipe diameters long for connections. (No close nipples accepted.)
Pumps-In-Line-Mounted

1. Mount pumps at locations show on drawings. Independently support motor of pump and piping on each side of pump so pump can be removed leaving piping intact. Provide 10 diameters of straight piping on suction side of pump, or provide suction diffuser.

1. Provide valves where shown and as required for isolation of equipment requiring service.

2. Provide system low point drain valves with hose end connection and with cap to affect a double seal.

3. Per Section 15400.

D. Automatic Flow Control Valves

1. Provide hydronic units, unit heaters, coils, and where required for proper operation of three-way control valves or Hydronic system balancing. Coordinate with Sections 15850 and 15900.

2. Install per manufacturer’s instructions.

E. Unions

1. Provide where shown on drawings and adjacent to all tanks, coils and other equipment requiring removal or replacement for service.

F. Expansion Joints

1. Provide where shown on drawings. Submit shop drawings showing anchor construction and attachment details to structural members.

G. Strainers

1. Provide where shown and upstream of all pumps.

H. Air Vents

1. Provide where shown on drawings and at all piping system high points.

2. Provide a minimum ¾” pipe size chamber below automatic air vents to collect air.

I. Pressure Gauges

1. Provide pressure gauges where shown and across the suction and discharge of all pumps of 10 gpm and greater capacity. Use one gauge assembly with isolation valves for reading suction, discharge, or differential pressure.

J. Temperature Gages

1. Provide temperature gages where shown and as follows:

a. At inlet and outlet of each boiler.

(17) Controls

A. Install all temperature wells, valves, and other control items furnished by controls contractor under Section 15900.

(18) Testing and Cleaning

A. Clean system using following procedure:

1. Pressure flush system with water to remove mill scale and dirt.

2. Flush all piping with a tri-sodium-phospate (TSP), or equal two ounces per gallon of system water to remove grease or equivalent cleaning agent. Pump solution through system at 180 degrees Fahrenheit for four hours.

3. Repeat process until the system is clean to the satisfaction of the PSD No. 1.

4. Submit certification of flushing prior to charging system with glycol solution to the Architect-Engineer and PSD No. 1.
B. Hydrostatically test the system at 120 psig with no pressure drop over a four-hour period after system temperature has stabilized.

C. Observe the system for leaks, faulty circulation, expansion and contraction clearances, during the foregoing operations. Note and correct all deficiencies.

D. Exercise proper care during cleaning and testing of the system to insure no damage is done to any valves, fittings, or work of other trades involved in this project. Restore any system, components thereof, or work of other trades, so damaged, to new or original condition at no additional cost to the owner.
Section 15550, Boilers and Accessories
(1) Description: This section describes hot water boilers and air-heating equipment.

(2) Submittals per Section 1300. Include sequence of operation for Boiler

Management System.

(3) Heating Hot Water Boilers and Accessories

A. High Efficiency Condensing Boiler:

1. Furnish and install LATEST GENERATION natural gas fired Clever Brooks Clear Fire Condensing MODEL CFC (size to be determined) modulating combustion hot water boiler as required. Provide with stainless steel tubes and tubesheets and /or stainless steel combustor, stainless street exhaust pipes, and vibration/sound reduction package as required. Provide 2-year extended parts warranty in addition to the standard warranty for all parts.

2. Each unit shall be modulating combustion type complete with boiler fittings and automatic “Falcon” on board controls. The boiler (with all wiring) shall be completely factory assembled as a self-contained unit. Each boiler shall be neatly finished, thoroughly tested and properly packaged for shipping. Boiler design and construction shall be in accordance with Section IV of the ASME Code for hot water heating boilers with maximum water working pressure of 60 psi. Boiler shall also comply to CSD-1 Code requirements.
The boiler shall have no minimum flow requirements or minimum return water temperature requirements and be suitable for use with 35% Propylene Glycol Solution. The boiler shall be a firetube design.
The combustor head and tubes shall be stainless steel construction. The pressure vessel shall be fully insulated with 2” of high temperature insulation. The exhaust pipes shall be stainless steel construction.

3. Boiler shall have a minimum firing rate input of (to be determined) MBH. Operating efficiency shall range up to 98% depending on return water temperature.

4. The flame safeguard shall be as required. The control shall provide a pre-purge and post purge. The control may maintain a running history of operating hours, number of cycles and the most recent flame failures. This control may have the capability to be connected to a keyboard display module which will retrieve that information.
Each boiler shall be of the unitized venturi, Gas Valve, Burner and burner head. This pre-mix design shall utilize a variable speed fan connected to a venturi to simultaneously modulate fuel and air. Turn down shall be 5:1 minimum.
The combustion location shall be such that all combustion assembly components are located within water backed areas. Combustion controls shall be LATEST GENERATION integrated microprocessor-based controller and shall perform the following functions.

a. Electronic ignition. Auto restart upon resumption of power after failure.

b. Burner sequencing and flame supervision with safe start check, pre-purge, electronic direct spark ignition, and post purge. Flame rod to prove combustion.

c. Modulating combustion fan and burner modulation over a 5:1 turndown ratio.

d. Safety shutdown with display of error.

e. Low gas pressure, air proving, high limit, and frost protection.

f. The supply temperature and set point temperature shall be displayed at all times by an LED readout. Output shall be a continuous PID via 4-20 mA current. (The control shall have the ability to reset the boiler water temperature based on outside air temperature or an input signal from a building management system) (see section 15900)
Controller shall have an option for communication device to computer interface for commissioning and advanced diagnostics.
All controls to be panel mounted and so located on the boiler as to provide ease of servicing the boiler without disturbing the controls and also located to prevent possible damage by water according to CSA requirements. Electrical power supply shall be 208/220/230 volts, 60 cycle, single phase, (verify) with a control circuit transformer to reduce voltage to 120 volts for control circuit requirements only.

5. Any pressure vessel shall be guaranteed against thermal shock for 20 years when utilized in a closed loop Hydronic heating system with a temperature differential of 170 degrees for less. All other components are covered by a two-year warranty.

2. 
   Boiler Management Control System
   

2. Use the following paragraph for application with up to (5) boilers and up to (3) sequenced header pumps:

a. Supply a fully integrated boiler control system to coordinate the operation of (2) fully modulating hot water boilers, (2) header primary water circulating pumps and boiler water flow control valves in order to maintain the hot water supply (HWS) temperature at setpoint. The control system shall be microprocessor-based and suitable for wall mounting.

3. Use the following paragraph for application with up to (5) boilers and (1) header pump with a variable frequency drive (VFD):

a. Supply a fully integrated boiler control system to coordinate the operation of (2) fully modulating hot water boilers, (1) header primary water circulating pump with a variable frequency drive (VFD) and boiler water flow control valves in order to maintain the hot water supply (HWS) temperature at setpoint . The control system shall be microprocessor-based and suitable for wall mounting.

4 Use the following paragraph for application with up to (7) boilers and boiler pumps with a variable frequency drive (VFD):

a. Supply a fully integrated boiler control system to coordinate the operation of (2) fully modulating hot water boilers and boiler primary water circulating pumps in order to maintain the hot water supply (HWS) temperature at setpoint. The control system shall be microprocessor-based and suitable for wall mounting.

b. The control system shall incorporate a HWS header temperature PID control scheme. Boilers shall be modulated in “Unison” (all at the same firing rate) to optimize the efficiency of the boilers. Modulation signals shall be 4-20 MAdc and shall be electrically isolated channel-channel and channel-ground.

c. When the HWS temperature control loop is in the “automatic” mode, the control system shall establish the HWS temperature setpoint based on the time of day, day of the week and outside air temperature. When in “manual” mode the operator may set the HWS temperature via a front panel display. All temperatures and time/date data must be field adjustable through “fill-in-the-blanks” style displays. Alternately, the control system shall accept a 4-20 mAdc outdoor air temperature reset setpoint signal from an external Building Automation System (BAS).

d. The control system shall utilize both HWS temperature and boiler firing rate percent to start and stop the boilers and shall minimize the total number of boilers in operation. The controller shall start and stop boilers when the HWS temperature is outside the adjustable temperature limit for longer than the adjustable time delay. In order to minimize header temperature deviations the control system shall start and stop the next boiler when the “lead” boiler is at an adjustable firing rate limit for longer than the adjustable time delay. The control system shall monitor both boiler lockout and limit circuits to automatically skip over those boilers that are powered down for maintenance, tripped or otherwise will not start. The lead boiler shall either automatically rotate every 1 to 168 hours or shall be manually selected by the operator. The boiler shall be run at low fire for warm-up for a preset low fire hold time. The base load ramp rate shall be field adjustable. The control system shall reduce the firing rate to a minimum before stopping a boiler to prevent accumulation of fuel in the furnace.

e. Provide main header primary water pump control to improve fired equipment availability. Start the quantity of header pumps as required for the number of boilers in operation. The control system shall monitor pump outlet flow switch status to automatically start a standby pump when a command to start the pump fails to produce flow. System must keep at least one pump running to ensure water is always moving past the header temperature sensor even after the last boiler has been stopped.

5. Use the following paragraph for sequenced header pumps or a single header pump with a variable frequency drive (VFD). If you are specifying a system with boiler pumps delete the following paragraph:

f. Provide boiler water flow valve control to prevent water from flowing through off-line boilers and lowering the HWS temperature); continue water flow for an adjustable cool down period after the boiler has stopped; and ensure water is always moving past the header temperature sensor even after the last boiler has been stopped. The valve shall be immediately closed if any trips occur during pre-purge, pilot, or main flame trial for ignition.

g. The control system shall include a 16 line x 40 Character (or greater) LCD display for boiler sequence control and status, alarm and event summaries, and setup menus for easy operation, tuning and troubleshooting. Alarms, events and operator actions shall be logged with Time/Date stamp and English language description. The control system shall include a minimum of 200 point memory. The control system shall include a minimum 100x150 pixel historical trending display or a paperless chart recorder or other videographic hardware to permit the logging of at least 32 data points for at least 45 days. Provide a minimum of 4 “pens” per chart with 8 minute thru 24 hour chart “width’ selections available.

6. In the following paragraph the reference to “valve” applies to applications with sequenced header pumps or a single header pump with a VFD only. If you are specifying a system with boiler pumps delete the reference to the valve:

h. Include hard wired backup stations to permit manual operation of the plant should the control system require service. Manual operation must be possible when the microprocessor is not functioning. Hard wired “Hand-Off-Auto” control switches must be wired directly into every boiler, pump, and valve Start/Stop circuit. Each 4-20 mAdc modulating control output must include a hard wired manual backup station with Auto/Manual switch, output control knob and output level indicator (bar graph, analog meter or digital display).

i. The control system shall include simultaneous communication to a Data Acquisition System (DAS), Building Automation System (BAS) or Building Management System (BMS) via RS485 Modbus protocol and to a Personal computer and an alphanumeric pager via standard telephone lines. The individual boiler limits, lockout, start/stop, warm standby, and firing rate status shall be readable. Header setpoint, plant firing rate, boiler quantity called to start, boiler selected as lead, and all setup parameters shall be readable and writable. (Coordinate with Section 15900)

7 Use the following paragraph for applications with sequenced header pumps. In the model numbers, “x” refers to boiler quantity and should be replaced with a number from 2 to 5; “y” refers to pump quantity from 2 to 3. If this configuration is selected, delete the following two paragraphs:

j. The control system shall be manufactured and labeled in accordance with UL508 requirements. Inspection and labeling shall be supervised by UL or other OSHA approved Nationally Recognized test lab (NRTL). The control system shall be a Preferred Instruments, Danbury, CT, Model JC-CDWHP-x-I-y with 190604 (Historical Trending) and 190603 (Telephone Modem) features. (Coordinate with Section 15900)

8. Use the following paragraph for applications with a single header pump with a Variable Frequency Drive (VFD). In the model numbers, “x” refers to boiler quantity and should be replaced with a number from 2 to 5. If this configuration is selected, delete the previous and following paragraphs:

k. The control system shall be manufactured and labeled in accordance with UL508 requirements. Inspection and labeling shall be supervised by UL or other OSHA approved Nationally Recognized test lab (NRTL). The control system shall be a Preferred Instruments, Danbury, CT, Model JC-CDHWHP-x-I with 190604 (Historical Trending) and 190603 (Telephone Modem) features. (Coordinate with Section 15900)

9. Use the following paragraph for applications with boiler pumps. In the model numbers, “x” refers to boiler quantity and should be replaced with a number from 2 to 7. If this configuration is selected delete the previous two paragraphs:

l. The control system shall be manufactured and labeled in accordance with UL508 requirements. Inspection and labeling shall be supervised by UL or other OSHA approved Nationally Recognized test lab (NRTL). The control system shall be a Preferred Instruments, Danbury, CT, Model JC-CDHWBP-x-I with 190604 (Historical Trending) and 190603 (Telephone Modem) features. (Coordinate with Section 15900)
The Boiler Management Control System shall have the following interface points for connection to the building, Energy Management Control System (EMCS). All connection points will be to a clearly labeled terminal strip within the BSCS:
Inputs:

Remote system supply water temperature setpoint (0-10VDC scaled to 100 deg. F to 200 deg. F) (verify and coordinate)

System enable/disable (open to enable)
Outputs:

System supply water temp (2-10VDC) (verify and coordinate)

System return water temp (2-10VDC) (verify and coordinate)

Boiler return water temps. (2-10VDC) (verify and coordinate)

Boiler run status (one per boiler)

Boiler failure signal (one per boiler)

General System alarm
The BMCS shall be supplied with the required number of 1000 ohm RTD’s with two wire 4-20 MA temperature transmitters correctly calibrated to jobsite conditions. Thermisters will not be allowed. Water temperature sensors shall be supplied with stainless steel dry immersion wells. Outdoor air sensors shall be supplied in a weather-tight wall mounted enclosure.
The BMCS shall utilize closed-loop PID control to sequence the associated boilers in a lead-lag format and stage their firing rates in response to the building system load so that only the minimum boiler capacity needed to meet the load is put on line and boiler cycling is minimized. Gain values of the P-I-D loop will be easily field adjustable though the panel mounted operator interface. The lead boiler will be automatically alternated base don operating (fuel valve open) hours; setpoint to be field adjustable.
In the “Remote” mode of operation the system supply water temperature setpoint will be supplied by the building’s EMCS. If that signal is not present or is out of range, the BMCS shall operate as a stand-alone temperature setpoint system.
In the “Local” mode the BMCS shall operate as a stand-alone temperature setpoint system.
The BMCS shall be able to determine if any boiler is available for use, if the safety limits are closed and if a boiler has been commanded on line and fails for any reason. If the lead boiler fails the lag boiler will be made lead until the fault in the lead boiler is rectified.
In the event of a failure with the automation, boiler mounted limits may automatically start and stop the boilers to maintain the back-up loop temperature set point (field adjustable). Boiler mounted backup modulation controls may control burner firing rate. This back-up mode transfer shall be made without operator input and can be manually forced by control panel selector switches.
The control panel shall be supplied by the boiler supplier who will assume single source responsibility for the operation of the boilers and controls.

C. The boiler supplier shall provide field services as follows:

1. Two 8 hours man-days for factory personnel designated following for start up and test of boilers and BMCS

a. Clever Brooks (Cole Industrial) “Dan Learn”

2. One 4 hour on site owner training session.

3. Provide written comprehensive start-up report detailing all aspects of boiler and boiler control system start-up procedure and start-up operating characteristics.

4. Provide 24 hour response for warranty service on the BMLS. Include overtime costs as required.

(4) Low Water Cutoff:

A. Provide for each boiler a McDonnell-Miller #63 (900 Series) low water cutoff wired in series with burner controls, where required by the State of Washington.

(5) Boiler Blue Venting:

A. The boiler shall be CSA approved as an indirect or direct vent boiler. Venting shall be accomplished with a stainless steel, double-wall, sealed vent piping installed in accordance with the vent manufacturer’s installation instructions and applicable national and local codes. Stack shall be category IV compliant for positive pressure, condensing applications. Vibration isolation components are not required.

(6) Flow Switch:

A. Provide flow switch to prove water flow for boiler operation, as required.

(7) Combustion Air Duct:

A. For direct venting the boiler shall have the combustion air intake supply

ducted with schedule 40 PVC pipe or round, single-wall galvanized sheet metal duct from outside. Combustion air duct shall be insulated to prevent the formation of condensation on the outside surface during periods of cold weather.

B. Slope toward boiler at ¼” per foot, install ASTM Schedule 40 PVC pipe, fittings, primer, and solvent cement.

(8) Set equipment on vibration isolators as required. Field route flue and combustion air to exterior. Level equipment to within proper tolerances. Submit shop drawings of proposed equipment layout and base.

(9) Anchor equipment to building structure using drop-in expansion anchors.

(10) Start-up Service:

A. After completion of the installation, start the heating plant in