1. Heating and cooling design loads for the purpose of sizing HVAC systems shall be determined in accordance with one of the procedures described in the latest edition of the ASHRAE
    2. Handbook of Fundamentals or equivalent computation procedures. The engineer shall furnish copies of applicable HVAC design calculations for review, along with periodic progress drawings.
    3. Outdoor and indoor summer and winter design temperatures used in the building load calculations shall be as follows for the Corvallis campus:
      1. Summer Outdoor Design for Classroom Buildings: 96°F. db and 67 °F.  wb.
      2. Summer Outdoor Design for Laboratory Buildings: 100°F. db and 67°F.  wb.
      3. Summer Outdoor Cooling Tower Design for Classroom Buildings: 97° F. db and 73 °F.  wb. Condensing Water Entering water temperature: 95°F.  and leaving water temperature: 80°F.
      4. Summer Outdoor Cooling Tower Design for Laboratory Buildings: 97° F. db and 73° F. wb. Condensing Water Entering water temperature: 95°F. and leaving water temperature: 80°F.
      5. Summer Outdoor Air Cooled Condenser Design ≤ 10 tons 95° F.db, ≥ 10 tons 105° F. db.
      6. Summer Indoor Design Office: 76 ° F.  at the work station. No Humidification.
      7. Summer Indoor Design Classroom: 76° F. No Humidification.
      8. Summer Indoor Design Lab 73° F. verify with the OSU Project Manager (PM). No Humidification.
      9. Winter Outdoor Design: 17° F, Wind @ 15 mph.
      10. Winter Indoor Design Office: 68°F. at the work station. No Humidification.
      11. Winter Indoor Design Lab: 68° F. at the work station. No Humidification.
      12. Winter Indoor Design Classroom: 68° F. at the work station. No Humidification.
      13. Summer/Winter Indoor Design for other rooms as directed by the PM.
    1. Design criteria listed below shall be used unless directed otherwise by the PM.
    2. The proposed type of building envelope construction shall be designed using thermal transmittance values (U value), which comply with the State energy Code requirement for thermal design.
    3. To prevent energy waste, all spaces with operable windows must have window-HVAC interlocks to prevent HVAC system operation with windows open.
    4. Equipment Loads
      1. General offices: 0.5 watts per sq.ft.
      2. Classrooms: 0.5 watts per sq.ft. or actual occupant load, with each occupant having a laptop computer, times 50%.
      3. Labs: based on actual equipment load plus 20%.
      4. Copy rooms: based on actual equipment load.
      5. Computer rooms: based on actual equipment load plus 20%.
      6. Corridors, walkways lobbies, etc.: None.
      7. MDF rooms: based on actual equipment load.
      8. IDF rooms: based on actual equipment load.
      9. The PM will provide equipment loads for specific spaces when applicable.
      10. When no specific data is available, use connected equipment electrical load (FLA) data with a 50% diversity factor.
    5. Occupancy Loads
      1. Minimum ventilation requirements based on latest edition of ASHRAE Standard 62.
      2. Use actual planning data plus 10%. Refer to ASHRAE values of 250 BTUH per person.
      3. General office: One person per 80 sq.ft.
      4. Conference rooms: One person per chair plus 20%.
      5. Labs: Base on one person per lab station.
      6. Classrooms: Base on one person per seat.
    6. Lighting Loads
      1. Minimum lighting loads based on NEC Table 220.12.
      2. When a lighting designer is included as part of the project team base lighting loads on actual room by room lighting loads designed by lighting designer.
    7. Minimum Outside Air Requirements
      1. Minimum requirements based on latest edition of ASHRAE Standard 62 or the Mechanical Code.
    8. Noise Criteria
      1. Open office space: RC 30-40.
      2. Private offices: RC 25-35.
      3. Conference rooms: RC 25-30.
      4. Classrooms maximum: RC 35.
      5. Laboratories: RC 35-45.
      6. Halls, corridors, and lobbies maximum: RC 40.
      7. Toilet and storage rooms maximum: RC-45.
      8. Video Conference Rooms maximum: RC-25.
    9. Provide for review a list of all pipe and duct systems with a brief justification of insulation and thickness, or of no insulation if none is specified.
      1. Include all field insulated equipment on the list.
    1. General
      1. Projects having total cooling requirements exceeding 50 tons of refrigeration should be designed around a central chilled system.
      2. Hydronic systems design shall ensure that valves, control fittings and piping are of alloys which shall not deteriorate when subjected to the water treatment chemicals and are optimum for the piping and heat exchanger service. Provide a test port on discharge side of all pumps.
      3. Locate mains and shutoff valves in hallways and corridors not in occupied rooms. Valves to be located within 18 inches of the main.
      4. Consider routing main lines on the first floor to serve the first and second floors and mains located on the third floor to serve the third and fourth floors of the building.
      5. All hydronic systems shall be flushed of foreign materials, chemically cleaned, flushed, and filled with the proper chemically treated water before being put into service.
      6. All closed loop water systems will have centrifugal air separator, bladder type expansion tank and make-up water connection connected as close as practical to the suction side of the circulating pump.
      7. Make-up water supply components will have isolation valves and union connections to allow removal for servicing. The make-up water supply will be connected on the circulating pump suction near the expansion tank connection. The make-up supply will include an isolation valve, a strainer, water meter, adjustable pressure regulator, safety relief and outlet check valve and isolation valve in that order. A valved by-pass line shall be provided around the make-up water pressure regulator assembly for initial system filling and emergency use. Provide ball valves in lieu of gate values for sizes 3-1/2” and smaller.
      8. All closed loop water systems will include a chemical addition tank with inlet filter, two (2) each Aqua Pure H1P748 or equivalent, connected in parallel across the circulating pump to allow continuous online partial flow filtering.
      9. All automatic vent devices must be provided with a manual isolation valve to allow replacement with system in operation. Devices with internal check valves are not sufficient to allow replacement with system in service.
      10. When glycol feed tanks are provided the feed system pressure shall be digitally controlled and alarmed similar to the Advantage Controls model.
      11. Glycol freeze protected systems will contain a minimum of 30% glycol.
    1. All chilled water coils mounted within ductwork will have internal provisions to collect and drain condensation to prevent condensate transfer and leakage from ductwork.
    2. In addition to any internal drain collection features all chilled and hot water HVAC systems will be provided backup leakage prevention measures that will contain any water condensation or leakage from the HVAC coil and prevent system condensation or leakage from migration to lower levels.
    3. HVAC unit housings are not permitted to be installed directly to slab or other flooring without a drain pan or waterproof membrane protective shield to collect condensation or leakage and prevent migration.
    4. Metal drain pans or berms with durable waterproof membranes will be provided under each AHU housings or coil to collect leakage when the coil or end turns are perforated
    5. Metal drain pans or berms will be alarmed to indicate leakage unless safe drainage is also provided.
    6. All condensate drains will be directly routed to floor drains. Condensate is not allowed to be pumped to the drain.
    1. Chilled water system flows and temperatures will vary based upon load, programming, scheduled or seasonal outages.
    2. New connections shall not be made to chilled water systems for the purpose of cooling process equipment or condensing units without the approval of the Facilities Services Energy Operations Manager.
    3. The primary-secondary pumping system arrangements for variable flow are to be used whenever possible.
    4. Multiple chillers are to be connected in parallel on the primary loop with each chiller served by a dedicated primary pump.
    5. Primary pump redundancy, if required, shall be provided by cross-connection lines with manual isolation valves and a stand-by pump.
    6. Secondary pumping redundancy shall be provided with a stand-by pump.
    7. Provide variable flow pumping schemes for secondary chilled water distribution loops.
    8. The primary loop piping to each chiller shall be provided with a flow measurement device such as a Venturi meter or Annubar unit, pressure gauges, industrial quality thermometers and thermowells and “Pete’s Plug” test points. Similar instrumentation shall be installed on secondary supply piping circuits.
    9. All chilled water coils will be provided duct drip pans internal to the ducting to collect and drain condensation.
    10. Design chilled water systems using schedule 40 black steel pipe on larger sizes and type L copper for smaller sizes.
    11. Fittings can be either, soldered, welded, flanged, threaded, or Victaulic type connectors depending on the pipe size.
    12. Chilled water piping systems
      1. Pressure drop: 4 ft. w.c. per 100 ft.
      2. Maximum velocity       
        1. Mains (equipment rooms): 10 ft. per sec.
        2. Mains and branches (other areas): 5 ft. per sec
    13. Chilled water system design temperature
      1. Chilled water: 10 - 20°F. temperature difference depending on manufacturer.
    1. Two types of piping and equipment arrangements shall be used.
      1. A one heat exchanger system shall have a pair of pumps connected in parallel, each sized for full load and located downstream of the heat exchanger. One pump shall be a spare and they both shall pump into the primary loop.
      2. If two heat exchangers are used, they shall be piped in parallel and connected to a common suction header connecting the pumps.
    2. Size single heat exchanger systems for the load. Size multiple heat exchanger systems so that each heat exchanger is sized for 100% of the load.
    3. The primary loop piping to each heat exchanger shall be provided with a flow measurement device such as a Venturi meter or Annubar unit, pressure gauges, industrial quality thermometers and thermowells and “Pete’s Plug” test points. Similar instrumentation shall be installed on secondary supply piping circuits.
    4. Hot Water System Design
      1. Design heating water systems using schedule 40 black steel pipe on larger sizes and type L copper for smaller sizes as approved.
      2. Fittings can be either, soldered, welded, flanged, threaded, or depending on pipe size.
      3. Hot water piping systems
      4. Pressure drop: 4 ft. w.c. per 100 ft.
      5. Maximum velocity
        1. Mains (equipment rooms): 10 ft. per second
        2. Mains and branches (other areas): 5 ft. per second
      6. Hot water system design temperature
        1. Heat Exchangers: 40 - 60°F. temperature difference
        2. Main coils: 20°F. temperature difference
        3. Re-heat / fan coils: 10°F. temperature difference
    1. Condenser water systems shall be designed with a pump and cooling tower for each chiller or with multiple (at least two) pumps located to discharge to a common pipe manifold with piping redistributed to each chiller. The designed system shall to minimize life cycles costs to the maximum extent practical while emphasizing energy efficiency.
    2. Tower systems designs shall consider the following criteria:
      1. Design temperatures for Outdoor and Condensing Water systems as specified in these standards.
      2. Water filtration.
      3. Water treatment.
      4. Open circuit versus closed circuit cooling towers.
      5. Sound and noise with respect to surroundings.
      6. Energy consumption.
      7. Capacity control utilizing variable frequency drives. Consider valves to proportionally control the water flow through a by-pass line to the tower basin when chillers are to be utilized and condenser water temperatures could be below 65 deg. F.
      8. Vibration isolation, including upper limit stops.
      9. Location of pumps and piping to ensure flooded suction on the pumps to prevent possible cavitation.
      10. Basin and make-up water heaters.
      11. Fire resistance of the tower components.
      12. Control of the tower water flow through the chillers as they are cycled on and off.
      13. Electric heaters or steam coils in the basin, for freeze protection.
      14. Insulate and heat trace exposed cooling tower condenser piping.
      15. Hose bib at location of tower for cleaning in future.
    3. Condenser Water System Design
      1. Design condenser water systems using schedule 40 black steel pipe.
      2. Fittings can be either welded, flanged, threaded, or Victaulic type connectors depending on pipe size.
      3. Provide a minimum of 20% extra tower capacity (BTUH, Flow, CFM) for future growth.
      4. No VFD Controls for water flow.
      5. Cooling tower piping systems
        1. Pressure drop: 4 ft. w.c. per 100 ft.
        2. Maximum velocity
          1. Mains equipment rooms: 10 ft. per sec.
      6. Condenser water design temperatures
        1. Design dry bulb: 97° F.
        2. Design wet bulb: 73° F.
        3. Entering water temperature: 95°F.
        4. Leaving water temperature: 80°F.
    1. Systems May Be:
      1. Single package for single zone applications.
      2. Single package for multi-zone-zone application.
      3. Split system air-cooled condenser/evaporator for cooling air or water.
      4. Split system water-cooled condenser/evaporator for cooling air or water.
    2. Systems shall be used where the life cycle is cost effective. If the system exceeds 50 tons, air cooled chillers may be considered for single unit with one per air handler for air handlers up to 400 tons.  One air cooled chiller for multiple air handlers up to 50 tons each. Obtain approval from the PM prior to designing the system incorporating such features.
    3. Direct Expansion Refrigerant System
      1. Design refrigerant systems using type L copper.
      2. Fittings to be copper to match piping, and brazed using a nitrogen purge.
      3. Size is based on manufacturer’s recommendations.
    4. Decommissioned refrigerant containing equipment shall display a weather resistant label clearly noting the removal of all hazardous materials, e.g. refrigerant, coolant, used oil, or any other hazardous material removed form unit.
    1. Color Coding of Pipe and Duct Labeling
      1. (See Color Coding of Pipe and Duct Labeling Chart at end of this Section)
    2. Identification of Concealed Valves and Equipment
      1. Affix a color coded “dot” to walls or ceilings wherever valves or other equipment are concealed. The colors shall be as follow
      2. (See Identification of Concealed Valves and Equipment Chart at end of this Section)
    3. Identification of Equipment, Pipes, and Ducts
      1. All plumbing, heating, air conditioning, piping, automatic temperature control equipment (excluding thermostats and relays), and distribution systems shall be labeled. Electrical switches and starters for mechanical equipment shall also be labeled.
      2. Equipment labels shall be black face plastic laminate with white engraved letters 3/16" high or larger, and shall be attached securely.
      3. Equipment nameplates shall include the following information at a minimum:
        1. Plan identification.
        2. Capacity specified at designed operating conditions.
        3. Actual capacity as balanced at site operating conditions.
        4. Area or zone served.
        5. All new installations of evaporator coil housing and condenser units shall have tags that states who installed the unit, a warranty contact phone number and warranty date, start to finish.
  10. PIPING
    1. All valves within the building, regardless of size and location, shall have brass or stainless steel tags at least 1" by 3" or two inch diameter in size and 0.051 inches thick. Lettering on the tag shall be engraved or stamped at least 3/16 inch high and match the valve numbers shown on the plans.
    2. Valve tags shall be connected to valve stems by steel rings and include the following minimum information:
      1. Plan Identification
      2. Normal Position
      3. Duty
      4. Area Served
      5. Valve Type
    3. Heating Water Valves, Steam Valves, and all Valves located in the secondary (low pressure) side of HTW Heat Exchangers shall include the Manufacturer, Size, Grade, and Pressure-Temperature service rating.
    4. Valve Tag Directory: Include tag number, location, exposed or concealed, service, valve size, valve manufacturer, valve model number, tag material, and normal operating position of valve. Include valve tag directory in the Operation and Maintenance Manuals and framed under glass on wall of mechanical room.
    5. All piping systems shall be properly identified with labels and signs indicating direction of flow and fluid. Identification shall be specified to have identification as outlined in the ASME (ANSI) Standard and current NFPA requirements. Provide a list of each system being installed with the appropriate name and label colors in the specifications.
    6. Comply with OSPSC Section 1003(r) regarding identification of non-potable piping systems.
    7. All accessible piping shall be color coded and identified with wording and arrows every 20 feet on straight runs, at each riser, at each junction, at each access door, adjacent to all valves and, flanges, on both sides of floor and wall penetrations and where required to easily identify the medium transported.
    8. Provide a trace wire for locating and identifying underground piping systems in the future.
    9. Provide marker tape one foot above the top of underground piping over the entire length of the pipe.
    1. General
      1. This section’s purpose is to establish standards of quality and utility for the mechanical components. The engineer’s task is to utilize equipment that provides the best value and lowest lifecycle cost while conforming to these standards.
      2. The quality of items not covered in these standards shall be of the same general level and be subject to the same tests of value as those that are included.
      3. Select items made by established manufacturers who have demonstrated the capability to provide replacement parts and service as may be required. The quality of the manufacturer’s local representation is very important.
      4. Analyze manufacturers’ designs for inherent maintenance qualities, as well as adequate access doors, fasteners, and other accessories, which will facilitate maintenance.
    1. Ease of operation, maintenance and repair, and safety of personnel are primary considerations for the design and installation of all items. Design for a minimum of 4 feet of clearance all around major items such as boilers, chillers, pumps, air handlers and fans unless the manufacturer’s recommendations or code requirements are greater.
    2. No equipment shall be installed in locations that will prevent future removal without major disruptions to the building or its contents. All equipment selected shall be designed for and provided with access doors and other accessories to address the requirements of this section. Connecting systems such as ductwork, piping, and electrical conduit shall be located so they do not obstruct access to the equipment service points.
    3. Provisions shall be made to allow easy access for hoisting heavy or cumbersome equipment onto elevated mechanical spaces.
    4. Critical wear components such as bearings, fan shafts, couplings, and belts shall be easily replaceable. Frequent service items shall be convenient; for example, easy access to filters and extended lubrication fitting.
    5. Equipment shall be designed so access doors, panels, guards, and similar items can be removed and replaced without special tools, so they are sturdy enough not to sustain damage under normal use and care.
    6. Provisions shall be made to provide a penthouse enclosure for rooftop equipment, when deemed suitable by the OSU Project Manager.
    1. Consider all appropriate sources of concern including radiated energy, energy transmitted through connecting items such as supports and electrical conduit, and energy transmitted through ducts, pipes and the fluids carried in them.
    2. Select equipment and specify isolators and attenuators to eliminate undesirable sound and vibration levels. Obtain approval for the design criteria from the OSU Project Manager.  If the design criteria is not established by an acoustical consultant use the following specifications:
      1. Vibration: Eliminate vibration which will be detrimental to the structure, its contents, or the activities taking place within the structure, or which would be annoying to the occupants.
      2. Sound: The operating systems should conform to the recommendations listed in the latest edition of the ASHRAE Handbook.
      3. Documentation: Provide documentation, for all office, conference room, classrooms, labs, and mechanical equipment areas showing actual sound levels at the project’s close-out.
    1. HVAC systems, equipment, and parts shall meet or exceed current applicable requirements for seismic resistance specified by codes, regulations, or agencies having jurisdiction.
    1. Drives and motors shall be specified to be provided by the same vendor to provide single source responsibility.
    2. Shaft to frame voltage difference shall be specified to be 3 volts or less to reduce the potential of bearing pitting to a minimum.
    3. Shaft grounding or bearing isolation shall be provided as directed from the OSU Project Manager.
    4. See Electrical: Section 26 00 00 for additional requirements.
    1. Specify multi-belt, adjustable speed drives rated at 150 percent of motor horsepower for constant speed motors which are 15 horsepower and smaller.
    2. Specify fixed pitch drives rated at 150 percent of motor horsepower for constant speed motors larger than 15 horsepower.
    3. Adjustable pitch drives shall operate at or near the midpoint range of adjustment when the equipment is balanced to the specified performance.
    4. Belt drives shall have fully enclosed guards. Outdoor guards shall be of solid metal construction; indoor guards shall be of expanded metal set in angle iron frames. Guards shall be constructed in two pieces to allow for belt and sheave adjustment without disturbing the guard supports. Specify 4” diameter tachometer holes with pivoted cover plates at each shaft. Guards shall comply with applicable codes.
    1. Electric motors shall have sufficient starting torque to start and drive the equipment load to which they are connected.  Motors shall be of the premium- efficiency type conforming to the latest State Energy Code requirements.
    2. Provide insulated motor bearings or shaft grounding on motors connected to variable frequency drives.
    3. Motor enclosures shall be:
      1. Drip-proof for general use.
      2. Totally enclosed, fan-cooled (TEFC) for wet or exterior use.
      3. Totally enclosed, air over (TEAO) for cooling towers.
    4. Motor voltages shall be:
      1. 1/2 HP or less: 120V, 1 phase.
      2. ¾ HP or greater: 460V, 3 phase.
      3. See Electrical Section 26 00 00 for additional requirements.
    1. Bearings shall be selected for 400,000 hours or better or L-10 life expectancy.
    1. Products installed exposed to the weather, moisture, or other potentially damaging conditions shall have their joints effectively sealed to prevent intrusion of moisture or other unwanted substances. Consider the use of heater in control panels and other items that could experience internal condensation. Tops of cabinets and equipment enclosures shall be designed to prevent puddling of liquids.
    1. Select the type of equipment best suited for the specified project requirements considering performance, flexibility, noise and vibration level, quality of construction, cost of ownership, and energy consumption.
    1. (See University Preferred HVAC Equipment with Stocked Parts Chart at end of this Section)
    1. Specify that the media access control (MAC) Address (Hardware address that uniquely identified the device node) for equipment (chillers, boilers, VFD’s etc.) that needs an Ethernet connection, is clearly written on the inside of the equipment control panel at the time the equipment ships from the factory.
    1. Systems testing, adjusting, and balancing is the process of checking and adjusting all the building environmental systems to produce the design objectives. It includes:
      1. The balance of air distribution
      2. Adjustment of system to provide design quantities
      3. Electrical measurement
      4. Verification of performance of all equipment and automatic controls
      5. Air Balancers must be registered engineers in the State of Oregon and have at least 3 years of testing, adjusting, and balancing experience similar to that required for OSU’s project. The Balancing contractor and project supervisor shall be NEBB or AABC Certified.
      6. NEBB: National Environmental Balancing Bureau
      7. AABC: Associated Air Balance Council
      8. Mark equipment settings, including damper control positions, valve indicators, fan speed control levers, and similar controls and devices, to show their final settings. Mark with paint or other suitable, permanent identification materials.
    1. Note 1: Steel grooved and fittings allowed on heating water systems in exposed areas only. Maximum of 180 degree F. water temperature.
    2. (See Piping Materials Chart at end of this Section)
    1. Piping Air
      1. (See Piping Air Manufacturers Chart at end of this Section)
    2. Handling Equipment
      1. Fans - general: Barry Blower, Twin City, Greenheck, Peerless, Cook.
      2. Fans – Fume Hoods: Plasticare
      3. Central Station Air Handling Units: Hunt Air, LogicAir, Haakon.
      4. Package Rooftop Air Handlers: Carrier, Trane McQuay.
    3. Chilled Water Equipment
      1. Chillers: Carrier and Trane.
      2. Pumps: Bell & Gossett, TACO, PACO.
      3. Inline pumps Bell & Gossett Series 60 or 80.
    4. Cooling tower: Baltimore Air Coil, Evapco. Provide a sewer deduction meter for cooling tower make-up water. Meter specifications found in Section 33 09 00 – Instrumentation and Control for Utilities.
    5. Heating Water Equipment
      1. Steam to hot water heat exchangers: Aerco, Armstrong, and ATT
      2. Direct buried steam and condensate piping: to be approved by Facilities Services.
      3. Condensate Pumps: PACO, Bell & Gossett maintenance free type. Steam injector pumps when feasible.
      4. Water Treatment:  Chem Aqua.
      5. Steam meter information is found in section 33 09 00 – Instrumentation and Control for Utilities.
    1. Particulate matter emissions from any fuel burning equipment installed, constructed, or modified after June 1, 1970 must not exceed 0.1 grains per standard cubic food, corrected to 12% CO2 or 50% excess air.  "Fuel Burning Equipment" means a device that burns a solid, liquid, or gaseous fuel, the principal purpose of which is to produce heat or power by indirect heat transfer. Particulate emissions for backup emergency generators is < 0.1 grain/ft3 (for new sources) or < 0.2 grains/ft3 (for existing sources).


Color Coding of Pipe and Duct Labeling


Identification of Concealed Values and Equipment


University preferred HVAC equipment with stocked parts

Piping Materials



Manufactures - Pining Air


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