Appendix_H_-_Mechanical_Design_Guide_July_2015.pdf

JULY 2015

Revision 1.2

Tobyhanna Army Depot

D/IS Engineering Branch Tobyhanna Pennsylvania

Mechanical Design and Construction Standards

Mechanical Design and Construction Standards

TABLE OF CONTENTS

1. GENERAL REQUIREMENTS…………………………………………….. 1

1.1 Preface…………………………………………………………………. 1

1.2 Criteria………………………………………………………….……… 1

1.3 Terms Used…………………………………………………………… 1

1.4 References……………………………………………………………. 1

1.5 Basic Principles……………………………………………..………. 1

2. FUNDAMENTALS………………………………………..………….……. 2

2.1 Calculations.………………………………………………………… 2

2.2 Design Requirements.……………………………………………... 3

3. SPACE TYPE SPECIFIC REQUIREMENTS…………..………….……. 7

3.1 Computer and Electronic Equipment Areas…………………… 7

3.2 Toilets, Lockers, and Utility Closets……………………………... 7

3.3 Vestibules……………………………..……………………………... 7

3.4 Mechanical Rooms…………………..……………………………... 7

3.5 Battery Rooms ……………………………………………………... 8

3.6 Kitchens and Dishwashing Rooms .……………………………... 8

3.7 Open Bays and Light Industrial Use Spaces…………………... 8

4. MECHANICAL EQUIPMENT PRODUCT AND INSTALLATION

REQUIREMENTS..............................................…………..………….….…. 7

4.1 Common Work Results for HVAC ………………….…………….. 7

4.1.1 Mechanical General Requirements ………………….………. 7

4.1.1.1 Motors and Drives………………….………………………. 7

4.1.1.2 Valves………………….……………………………………… 7

4.1.1.3 Pipe Hangers and Supports ………………….………….. 7

4.1.1.4 Sound and Vibration Control………………….…………. 7

4.1.1.5 Mechanical Identification………………….……………… 7

4.1.2 Measuring Instruments for HVAC………………….…………. 7

4.1.3 Testing Adjusting and Balancing ………………….…………. 7

4.2 HVAC Insulation……………………………………………………... 21

4.3 Instrumentation and Control for HVAC….………………….…... 23

4.4 Hydronic Piping and Pumps..……..………………………….…... 24

4.5 Steam and Condensate Piping and Pumps……………….…

4.6 Refrigerant Piping…………………….……………………………... 45

4.7 HVAC Water Treatment………………………...…………………

4.8 HVAC Ducts…………………………………….…………………..… 55

4.9 Air Duct Accessories………………………………………………... 56

4.10 HVAC Fans……………………………..…………………………… 57

4.11 Air Terminal Units.…………………..……………………….…

4.12 Air Outlets and Inlets (Diffusers, Registers, Grilles)………... 58

4.13 Ventilation Hoods …………………….……………………….…... 58

4.14 Particulate Air Filtration………………………..………………

4.15 Breechings, Chimneys, and Stacks………..…………………… x

4.16 Heating Boilers ………………………………………………..…... x

4.17 Heat Exchangers..…………………..……………………………... x

4.18 Furnaces………………………………..…………………………..... x

4.19 Packaged Compressor and Condenser Units………………... x

4.20 Packaged Water Chillers……………..………………………….... x

4.21 Cooling Towers………………………………………………...…... x

4.22 Air to Air Energy Recovery Equipment………………………… x

4.23 Indoor Central Station Air Handling Units ………………..…... x

4.24 Outdoor HVAC Equipment ………..……………………………... x

4.25 Decentralized Unitary HVAC Equipment ……………...……... x

4.26 Air Coils ……………………………………………………………... x

4.27 Radiant Heating……………………….…………………….……... x

4.28 Humidity Control Equipment………..…………………….……... x

1. CHAPTER 1 INTRODUCTION

1.1 Preface - These requirements are written for project designers. It is expected that these requirements will be used during design to understand the particular needs of TYAD. These requirements will help the designer as he prepares the plans and job specific specifications. Reference to standards is limited, as they will be covered in the job specific specifications.

1.2 Criteria - Unless otherwise specified either in this document or in the applicable UFGS, all designs shall comply with all applicable American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) criteria and guidance.

1.3 Terms Used - The terms “as approved”, “approved”, or “shall be approved” means that written approval shall be granted by the Engineering Branch of the Directorate of Installation Services, Tobyhanna Army Depot (TYAD). This office is the Authority Having Jurisdiction (AHJ) and is responsible for approving equipment, materials, an installation, or a procedure in accordance with the requirements of NFPA-70.

1.4 References - All applications shall be in accordance with the latest edition of the following documents and any listing requirements. Other referenced documents in the job specifications are also applicable. Where there is any conflict between references, the most stringent shall be applicable unless approved otherwise by the AHJ. AHJ shall approve the list of applicable codes.

1.5 Basic Principles - The designer shall base all designs on the following basic principles:

1.5.1 Sustainability - All design work shall be “sustainable” in accordance with ECB 2006-2 and comply with the requirements of ASHRAE 189.1. Additional design decisions should be selected based on life cycle cost effectiveness. The HVAC designer is required to meet the USGBC-LEED™ prerequisites and shall provide documentation for as many LEED credits as possible toward certification of the project.

1.5.2 Serviceability - Each design shall be as simple as possible while still meeting design constraints. Identify and note on drawings any space necessary to access items that require maintenance, such as filters, coils and drain pans, strainers, and chillers.

Provide systems with the features necessary for successful testing, adjusting, and balancing, system commissioning, and for easy access for maintenance. No equipment requiring periodic service shall be located in confined spaces or in areas that require special equipment other than a standard man lift to access.

1.5.3 Waivers - Where a valid need exists and an alternate solution involving sound engineering is available, designers may submit requests for a criteria waiver to the applicable AHJ. Requests for waiver must include justification, life cycle cost analysis, energy compliance analysis, criteria used, and other pertinent data.

2. FUNDAMENTALS

2.1 CALCULATIONS - Perform all necessary design analysis and calculations and submit for review with all drawing submissions.

2.1.1 Submit load summaries - Provide breakdowns for zones, major areas, subsystems and equipment loads. Include common engineering check figure ratios such as cfm/sq. ft., heating BTUH/sq.ft, and cooling sq. ft./ton.

2.1.1.1 Heating Load Calculations - Exclude anticipated internal and solar heat gains from heating load calculations. Increase the calculated size of equipment and distribution system by up to 30 percent where necessary to compensate for morning recovery due to night setback. Calculations shall include infiltration.

2.1.1.2 Cooling Load Calculations - Do not increase the calculated size of equipment and distribution system to compensate for morning recovery. Equipment capacity should not result in an increase above the size calculated of equipment and distribution system(s) of more than 10 percent total. Submit a psychometric plot of each air-conditioning system along with the calculations. Clearly identify all points in the conditioning process on the psychrometric chart and verify the sensible, the latent, and the total cooling capacity using the appropriate data from the chart. List the sensible, latent, and total capacity requirements for each cooling coil specified. For applications where reheat is required for humidity control, the capacity of the reheat will be equal to the total internal sensible heat generated in the area served.

2.1.2 Sound and Vibration control analysis - Perform calculations and selection of attenuation provisions for HVAC systems to maintain sound and vibration within acceptable levels for each application.

2.1.3 Economic / Life Cycle Cost Analysis – Perform and submit as required to confirm selection of base systems and potential options for alternate bids. The designer will evaluate all energy conservation items that appear to have potential for savings, such as heat recovery for HVAC and service water heating, economizer cycles, thermal energy storage, desiccant dehumidification, plastic door strips for loading docks, etc., and include those items in the design that are life cycle cost effective. Ensure that all operation and maintenance costs are included in the life cycle cost analysis.

2.1.4 Airflow Balance – Provide table of all air flows into and out of a given building or well defined area listing each source of exhaust and outdoor air, its maximum and minimum airflows, hours of expected operation, and totals of exhaust and outdoor air flow.

2.2 DESIGN REQUIREMENTS.

2.2.1 Outdoor Design Conditions - The following are general design guidelines for inside and outdoor design conditions.

Area Description Season Indoor Outdoor Comments

Comfort Areas Summer Winter

75°F DB/50%

72°F DB/25%

90°F DB 74°F WB

0°F DB

1, 2

Asset Critical Areas Summer Winter

Consult /User Consult /User

92°F DB 74°F WB

-5°F DB

Freeze Protection Winter

40°F DB

-15°F DB 4

Heat Rejection Equipment Selection

Summer Winter

95°F DB 3

Notes:

1. Consideration shall be given to morning warm-up cycle.

2. Operating control setpoints shall be as follows:

a. Comfort Areas such as general office

i. Occupied: 70 heating, 75 cooling

ii. Unoccupied: 60 heating, 85 cooling

3. Consideration shall be given location of equipment and if localized elevated temperatures may such as on a black roof.

4. Water coils exposed to outdoor air shall contain 30% propolene glycol solution

2.2.2 Infiltration - Design air distribution systems for central HVAC systems to maintain a slightly positive pressure within the area served in order to reduce infiltration unless there is a valid need to maintain a negative pressure in that area. Heating load calculations should include infiltration.

2.2.3 Part Load Operation - Carefully evaluate system turndown requirements.

Consider modular, multiple unit configurations where effective and practical for proper and efficient low part load operation and to help prevent complete system or building shutdown upon failure of a single primary HVAC system component.

2.2.4 Indoor Air Quality (IAQ) - Ventilation for acceptable IAQ will be in accordance with ASHRAE Standard 62.1. Successful application of IAQ principles and criteria plays a role with regards to HVAC systems in ensuring occupant comfort and health. Good IAQ design practice increases worker productivity.

2.2.4.1 Ventilation Air Intakes – All ventilation air intakes shall be meet the following requirements:

Bottom of openings must be at least 10 feet above ground level

Must be located with consideration for entrainment of pollutant sources such as plumbing vents, combustion exhausts, idling vehicles, etc.

2.2.4.2 Ventilation Schedule - Provide a ventilation schedule on the drawings, perhaps combined with the diffuser/register schedule. This schedule should assist the building occupants when performing future renovations. List the total supply air and the number of anticipated occupants for each room in the schedule. Add a footnote to each schedule indicating that the number of occupants listed is for information purposes only.

2.2.4.3 Air-Water Systems - Consider combinations of air and water systems such as radiant heating supplemented with single-zone interior air supply for ventilation;

hydronic systems at the periphery of a building to offset skin transmission losses only, combined with the use of an air system for space cooling and ventilation loads.

2.2.4.4 All Air Systems - Where outdoor design temperatures are 20 degrees F or below, consider all air systems only in conjunction with double glazing, where sedentary activities are a minimum of 3 feet from the glass, and where proper peripheral air distribution is provided. Use preheat coils whenever the mixture of return air and ventilation air at outside design temperature is below 35 degrees F.

Ducted supply and return systems are required. Return plenums are not permitted unless prior approval is received.

One hundred percent shutoff VAV systems are not permitted. Minimum airflow must be maintained to satisfy ventilation requirements. Reheat shall be provided for all interior and exterior zone VAV boxes.

Economizer cycle (temperature controlled) shall be utilized on all systems for areas requiring year-round cooling.

For all systems five tons and over utilizing economizer cycles a separate return or exhaust fan must be utilized to provide positive relief and also standby capacity in the event of supply fan failure.

Prior approval must be received and 100% auxiliary heat must be provided.

2.2.4.5 Dedicated Outdoor Air Systems - Ventilation systems that are independent of the primary air supply and distribution systems are preferable as they can provide benefits such as increased humidity control, reduced amount of ventilation air than may be otherwise required, and increased equipment operating efficiency.

2.2.4.6 Purge Cycle - Where desirable, the designer may incorporate a purge mode into system design. This mode could be used, for example, to purge the building with outside air during off-hours or to purge an area of the building undergoing maintenance, such as painting.

2.2.4.7 Indoor Pollutant Source Exhaust – locations designated for photocopiers, laser printers, cleaning supplies, or other potential air contamination sources shall have local exhaust. As much as possible, maintain the area at a negative pressure relative to adjacent areas by transferring air from these adjacent areas. Do not add the air exhausted from the local exhaust to the return air or transfer it to any other areas.

2.2.4.8 Filtration - For administrative facilities, commercial facilities, and similar facility occupancy classifications where indoor air quality is of primary concern, it is preferable to filter the combined supply air, including return and outside air, with an extended surface filter with a MERV of 13 when tested in accordance with ASHRAE Standard

52.2. Where practical, provide separate filtration or other means to clean the outdoor air, typically equivalent to that used for the combined air stream, prior to mixing it with the return air. Due to the decrease in system airflow as the pressure drop across the filter increases, size fans for the “dirty” filter condition. This will ensure that each fan has adequate capacity to deliver the design airflow as the filter becomes loaded.

2.2.5 Duct Design.

2.2.5.1 Test and Balance - Ensure that duct design incorporates all features necessary to accommodate testing, adjusting, and balancing (TAB). For example, provide adequate length of duct, both upstream and downstream of fans and coils. Show the necessary fittings, transitions, test ports, etc. required for successful TAB, for duct inspection and cleaning, and for damper access and inspection. UFGS 23 05 93 Testing, Adjusting, and Balancing contains many of the requirements of HVAC testing, adjusting, and balancing including strict quality control guidelines that the construction contractor must meet in order to verify that the HVAC systems have been properly installed and operating as specified. All features required for successful TAB must be shown on the design drawings.

2.2.5.2 Prohibited Designs Elements - Do not use the following types of construction:

Plenum Returns. All returns shall be ducted.

Sub-slab or intra-slab HVAC ducts.

Plenum-type, subfloor HVAC systems, as currently defined in Federal Housing Administration minimum acceptable construction criteria guidance.

HVAC ducts in uninsulated attics.

HVAC systems where any part of the ducting is in contact with or exposed to the ground.

Fiberglass acoustic duct lining or internality insulated ducts shall not be used in supply ductwork. If lining is needed for acoustic purposes is must be of an elastomeric type.

2.2.6 Controls - Design HVAC controls in accordance with TYAD guide spec 23 09 23 Direct Digital Control for HVAC and Other local Building Systems and TYAD guide spec 25 10 10 Utility Monitoring and Control Systems (UMCS).

2.2.7 Seismic Protection - Design HVAC systems with respect to seismic protection in accordance with the International Building Code.

2.2.8 Commissioning - The use of UFGS 23 08 00.00 10 Commissioning of HVAC Systems is mandatory for all Army projects.

2.2.9 Refrigerants – Chlorofluorocarbons (CFC) and Hydro Chlorofluorocarbons (HCFC) are not permitted for use. All new equipment may only utilize hydro fluorocarbons (HFC). Where refurbishment or demolition of mechanical refrigeration equipment is involved, provide detailed step-by-step guidance and diagrams that comply with the recommendations of ASHRAE Handbook Refrigeration in the design.

2.2.10 Water Treatment - If an analysis is unavailable, obtain a sample of the raw water. Test the sample and include the results in the applicable contract specifications.

Design water treatment systems for boilers in accordance with UFC 3-430-02FA Central Steam Boiler Plants, or UFC 3-430-04FA High Temperature Water Heating Systems.

Provide water treatment systems for cooling towers for prevention of corrosion, scale, and biological formations. In most cases, a water treatment system is required for closed chilled-water systems, hot water systems, or dual-temperature systems.

2.2.11 Mechanical Ventilation for Industrial Applications - For applications not covered by ASHRAE criteria, use the ACGIH Industrial Ventilation, A Manual of Recommended Practice.

2.2.12 Utilities Impact - Perform analysis of existing utilities and/or existing HVAC infrastructure and submit summary of required upgrades to support new work. Each project is responsible for funding all utility infrastructure upgrades made necessary by that project.

2.2.13 Mechanical Identification - Coordinate identification nomenclature with TYAD Standards per Spec. 01 31 01 TYAD GIS Identification Requirements

2.2.14 Existing Systems - Numerous boilers, gas fired air rotation units, and steam condensate return systems were installed as part of an Energy Savings Performance Contract where operations and maintenance responsibility of this equipment is by a non government contractor. Additional limitations may exist if scope of work impacts any of these systems.

3 SPACE TYPE SPECIFIC REQUIRMENTS

3.1 Computer and Electronic Equipment Areas - Deviate from the indoor design conditions required for comfort conditioning, including temperature and humidity limits, only to the extent required to support the computers and electronic equipment, including communication, surveillance, and research related equipment, to be housed within the area. If practical, use two or more smaller units to satisfy the required cooling capacity.

This will generally reduce energy consumption at partial cooling loads and will also increase overall system reliability. Where an under-floor supply air plenum is used in conjunction with above ceiling return, design the number and size of outlets in the raised floor to deliver 80 percent of the total supply air. The remaining 20 percent of the supply air should be routed to the room via cable cutouts in the raised floor. Specify supply registers suitable for installation in floors on which it is anticipated that equipment will be moved. Locate ceiling return registers near heat producing equipment.

Utilize free cooling option for computer room systems when it is cost effective.

3.2 Toilets, Lockers, and Utility Closets - Maintain these areas at a negative pressure relative to adjacent areas by exhausting air transferred from these adjacent areas to the outdoors. Where possible, the heating equipment capacity or energy consumption will not be increased by these areas.

3.3 Vestibules - Vestibules may be heated to 50 degrees F (10 degrees C) to melt tracked-in snow in locations where conditions warrant. Otherwise, vestibules will not be heated or air conditioned.

3.4 Mechanical Rooms - Mechanical rooms shall be designed in accordance with the most current version of all applicable codes.

Mechanical rooms shall be planned with sufficient size and equipment laid out to provide adequate maintenance clearances for all equipment; (i.e. for filter changes, tube and coil pull spaces, repair of components, etc.). Adequate means of access shall be provided for replacement of largest piece of equipment without removing general construction or moving other equipment. Minimize the need to do maintenance from ladders. Provide overhead structural steel with portable chain hoists to lift heavy motors, compressors, fans, etc. Provide adequate lighting.

Mechanical rooms shall be provided with a minimum of one floor drain. Floor drains shall be piped to sanitary system.

Provide mechanical rooms with minimum one hose bibb with backflow preventer in supply piping.

All equipment drains, blow down lines, etc. shall be piped to a floor drain with an approved air gap fitting.

Mechanical rooms will usually be ventilated using outside air intake louvers and a thermostatically controlled exhaust fan. Use a supply fan in lieu of an exhaust fan in rooms where atmospheric burners are located. The ventilation fan will be sized, at the high speed, to have adequate capacity to limit the room dry bulb temperature to a maximum of 15 degrees F above the outdoor dry bulb temperature when both equipment and ambient loads are at their maximum peaks.

Mechanical rooms shall be located to provide access directly from the building exterior.

Mechanical rooms shall not be located where vibration and/or noise would be objectionable.

3.5 BATTERY ROOMS - Design battery rooms/areas in accordance with UFC 3-520- 05.

3.6 KITCHENS AND DISHWASHING ROOMS

Ventilation will be the chief means of preventing heat, odors, and smoke from entering dining areas and other adjacent spaces. Provide evaporative cooling where effective.

Spot air conditioning or general air conditioning may be provided to keep temperature in the work areas from exceeding 85 degrees F, if the main portion of the facility is air conditioned and the criteria for exhaust ventilation are met. Provide a separate ventilation system for the dishwashing area. Furnish tempered 65 degrees F db min makeup air for the range hood exhaust. Do not recirculate more than 75 percent of air (excluding hood exhausts) in the kitchen at any time. Kitchen canopy hood exhaust ventilation rates will generally be 75 fpm for grease filter sections, and 50 fpm for open hood section, measured at the horizontal hood opening. As an alternative, internal baffle-type canopy hood with peripheral slot and a slot velocity of 500 fpm is recommended. Use electrically interlocked supply and exhaust air fans designed for 2-speed operation.

When substantial quantities of hot air exhausted from kitchen areas do not contain grease, consider using air-to-air heat exchangers in order to recover as much energy as possible. Evaluate the use of heat recovery in kitchens where heat rejected by refrigeration equipment is 50,000 Btu/hr or more.

Dishwasher room exhaust ducts will be as short as possible with direct runs to outside of building. Ductwork will have watertight joints and will have a drain line from the low point. Approximately 75 percent of the room air will be exhausted at the dishwasher, with the remainder exhausted at the ceiling. Dishwashers normally have duct collar connections so that exhaust ducts can be attached directly.

3.7 Open bays and light industrial use spaces

These spaces are not typically air conditioned. In these areas, elevated summer ventilation may be used to provide some level of summer comfort control. Consider augmenting ventilation systems with nighttime air flushing of spaces, multi-speed fans, increased insulation, improved shading, and exhaust of heat emitting sources to improve the effectiveness of comfort ventilation.

4 MECHANICAL EQUIPMENT PRODUCT AND INSTALLATION REQUIREMENTS

4.1 Common Work Results for HVAC

4.1.1 Mechanical General Requirements

4.1.1.1 Motors and Drives

4.1.1.1.1 Motors

All motors over 1/2 hp shall be ball bearing unless otherwise noted.

All ball bearing motors shall be equipped with lubricating type bearings, and provided with one (1) grease fitting per bearing and one (1) removable plug per bearing in the bottom of the grease sump to provide for flushing and pressure relief when lubricating.

Motors shall be permanently marked that bearings are lubricating type bearings. Where motor grease fittings are not accessible, extend 1/8" steel or copper tubing from fitting to an accessible location.

Motors 3/4 hp and larger to be three phase, 60 hertz.

Motors smaller than 3/4 hp to be single phase, 60 hertz, 120V and shall have built in thermal protection.

All motors above 1 hp shall be the low loss - high efficiency type. Motors shall be tested in accordance with NEMA standard MG1 1.536 and name plate shall indicate the index letter.

All 3-phase motors larger than 5 hp shall have power factor correction capacitors as recommended by the manufacturer.

4.1.1.1.2 Drives

All belt driven equipment shall include properly selected adjustable sheaves and matched V belts, all rated for 150% of motor horsepower. Proper expanded metal guards should be provided for safety protection and to allow for proper ventilation for cool operation of belts. Solid sheaves and band belts shall be used to minimize vibration in multiple V-belt driven equipment.

Motor grease fittings shall be extended so belt guards do not need to be removed.

All adjustable sheaves shall be replaced with suitable fixed sheaves prior to final acceptance.

4.1.1.2 Valves

4.1.1.2.1 General

All valves on any one project shall be the product of one manufacturer.

Valves shall have right hand threads.

Where possible, valves shall be installed with valve bonnet in an upright position to prevent deterioration or corrosion of bonnet and packing.

Valve body materials shall be compatible with piping system materials.

4.1.1.2.2 Check Valves

Where check valves are required, check valves shall be installed on the equipment side of all shutoff valves to facilitate servicing the check valve.

4.1.1.2.3 Drain Valves

Drain valves shall be a minimum of 3/4" with hose end connection.

4.1.1.3 Pipe Hangers and Supports

Provide an adequate pipe suspension system in accordance with the current version of the International Mechanical Code, recognized engineering practices, using standard, commercially accepted pipe hangers and accessories. The use of pipe hooks, chains, or perforated iron for pipe supports will not be accepted.

Contractor shall submit Data sheets for approval on all pipe hanger items prior to installation.

All piping shall be arranged to maintain the required pitch and provided for proper expansion and contraction.

No holes are to be drilled or burned in structural building steel for hanger rod supports.

Vertical runs of pipe shall be supported with riser clamps made specifically for pipe or for tubing.

Where concentrated loads of valves and fittings occur, closer spacing may be necessary. Hangers must be installed not more than 12 inches from each change in direction of pipes.

All hangers for piping shall be provided with a means of vertical adjustment. If adjustment is not incorporated in the hangers, use turnbuckles.

Provide piping suspension systems with vibration isolation capability as required.

Copper clamps and hangers shall be used on copper piping.

4.1.1.4 Sound and Vibration Control

4.1.1.4.1 Sound and Vibration Control

Mechanical and electrical equipment and associated piping and duct work shall be mounted on vibration isolators as required to minimize transmission of noise and vibration to the building structure or spaces within.

All rotating equipment shall be balanced both statically and dynamically. The equipment supporting structure shall not have any natural frequency within plus or minus 20% of the operating speed.

Isolation shall be stable during starting and stopping of equipment. Lateral thrust restraint isolators shall be provided where necessary to prevent excessive lateral movement under equipment start-up and stop conditions. Lateral thrust isolators shall not interfere with vertical isolation.

Isolation shall be selected for the operating speed of the equipment. Where the equipment is controlled by a variable frequency drive, the isolator shall be sized for the lowest expected operating speed.

4.1.1.4.2 Equipment Isolation

Isolators located outdoors shall be hot-dipped galvanized.

Isolators shall be selected and located to produce uniform loading and deflection even when the equipment weight is not evenly distributed.

Unless otherwise specified, said base types, isolator types, and deflections shall be taken from the “Selection Guide for Vibration Isolation” table in the Sound and Vibration Control chapter of the ASHRAE Applications Handbook, current edition.

Fan and motor assemblies in air handling units may be internally spring isolated. In which case, external isolation shall not be provided.

Packages containing other rotating equipment, such as compressors and pumps, shall be externally isolated.

4.1.1.4.3 Piping and Ductwork

Vibration isolation shall be provided for piping and ductwork as follows:

All high pressure ducts (over 6” wg) for 50’ from vibration isolated air handling equipment.

All piping located in mechanical rooms, or for a distance of 50’, whichever is greater.

Pipe hanger isolators shall have the same deflection as that supplied for equipment to which the piping is attached.

The vibration isolator units selected shall not deter the thermal movement of the piping or the expansion compensator from performing its required task.

4.1.1.4.4 Flexible Connections

Flexible duct connections shall be provided adjacent to air handling equipment.

Flexible piping connections shall be provided at piping connections to all rotating mechanical equipment mounted on vibration isolators.

Flexible conduit, equal to 150% of the distance between motor connection and adjacent attachment point, shall be provided for electrical connections to all vibration isolated equipment.

4.1.1.4.5 Interior Sound Pressure Level Requirements

The maximum interior sound pressure levels, due to installed HVAC equipment, shall not exceed those shown in the table of design guidelines for HVAC-related background sound in rooms in the chapter of Sound and Vibration Control, ASHRAE Application Handbook, current edition, unless otherwise specified.

While these guidelines are labeled as RC values, they shall be interpreted as NCB guidelines (per ANSI Standard S12.2).

The RC Mark II method shall be used for investigating room noise problems in the field, per the above noted ASHRAE Handbook chapter.

4.1.1.5 Mechanical Identification

Coordinate identification nomenclature with TYAD Standards per Spec. 01 31 01 TYAD GIS Identification Requirements

4.1.2 Measuring Instruments for HVAC

4.1.2.1 General

Provide all measuring instruments as required to achieve proper balancing, calibration of electronic sensors, and routine inspection, maintenance and troubleshooting of mechanical systems.

Provide permanent gauges and thermometers on all central equipment and temperature / pressure control zones in all mechanical and utility rooms.

Provide pressure and temperature test plugs adjacent to all electronic pressure or temperature UMCS sensors in hydronic systems (for testing/calibration purposes), on all terminal heating and cooling equipment, and at temperature/pressure control zones in hydronic systems in non-occupied spaces, such as above ceilings or below raised floors.

Provide permanent venturi flowmeters on pumps; and on primary / dedicated hydronic flow control zones where flow/gpm point is scheduled on control sequences.

Provide instruments with scale ranges selected according to service.

Quality Assurance: Comply with applicable portions of ANSI, ASME and Instrument Society of America (ISA) standards pertaining to construction and installation of meters and gauges.

4.1.2.2 Products

4.1.2.2.1 Pressure Gauges

General: Provide pressure gauges of materials, capacities, and ranges indicated, designed and constructed for use in service indicated.

Type: General HVAC grade, 1% accuracy, ANSI B40.1 grade A, glycerine filled phosphor bronze bourdon type, rotary brass movement with front recalibration adjustment bottom connection.

Case: Aluminum or nylon, glass (or acrylic) lens, 4½" diameter typical

Connector: Brass with ¼" male NPT. Provide protective syphon when used for steam service.

Scale: White coated aluminum, with permanently etched black markings.

Set Hands: Where pressure gauges are indicated for use across pump suction diffusers or straining / filter devices, provide adjustable set hands to indicate recommended pressure ranges of system.

Range: Select for normal operating pressure to be approximately mid range of scale with full scale range shall be selected to be approximately 1.5 to 2.5 times the normal maximum operating pressure. The following typical ranges are suggested. The Professional shall select/specify final per specific system requirements:

Vacuum: 30" Hg - 30 psig (Compound)

Water:

0 - 15 psig (between 2 to 10 psig max operating pressure) 0 - 30 psig (between 10 to 20 psig max operating pressure) 0 - 60 psig (between 20 to 40 psig max operating pressure) 0 - 100 psig (between 40 to 60 psig max operating pressure) 0 - 160 psig (between 60 to 100 psig max operating pressure) 0 - 200 psig (between 100 to 130 psig max operating pressure) 0 - 300 psig (between 130 to 200 psig max operating pressure)

Steam:

0 - 200 psig (High Pressure – up to 125 psig max operating) 0 - 100 psig (Medium Pressure – up to 50 psig max operating) 0 - 30 psig (Low Pressure – up to 15 psig max operating)

4.1.2.2.2 Gauge Attachments

Snubbers: ASME B40.100, brass; with ¼” NPT, ASME B1.20.1 pipe threads and porous-stainless steel filter-type surge-dampening device. Include extension for use on insulated piping.

Siphons: Loop-shaped section of brass (for normal operating pressure/temperature up to 200 psi, 325 F) or stainless-steel (for normal operating pressure/temperature greater than for brass) pipe with ¼” NPT pipe threads.

Valves: Brass body, stainless ball, selected for working pressure suitable for application, with ¼” NPT, ASME B1.20.1 pipe threads.

4.1.2.2.3 Liquid in Glass Thermometers

General: Provide stem type glass thermometers, per Standard ASME B40.200, of materials, capacities, and ranges indicated, designed and constructed for use in service indicated.

Case: Die cast aluminum finished in baked epoxy enamel, glass front, spring secured, 9" long, acrylic or glass window face.

Adjustable Joint: Die cast aluminum, finished to match case, 180 adjustment in vertical plane, 360 adjustment in horizontal plane, with locking device.

Tube and Capillary: Glass with magnifying lens, blue or red organic liquid (non-mercury), 1% scale range accuracy, shock mounted.

Scale: Satin faced, non-reflective aluminum, permanently etched markings.

Stem: Copper-plated steel, aluminum, or brass, for separable socket, length to suit installation.

Design for Thermowell Installation: Bare stem.

Design for Air-Duct Installation: With ventilated shroud.

Accuracy: Plus or minus 1 percent of scale range or one scale division, to a maximum of 1.5 percent of scale range.

Range: Full scale range shall be selected to be approximately 1.33 to 2.0 times the normal maximum operating temperature. The following typical ranges are suggested.

The Professional shall select/specify final per specific system requirements:

Chilled Water (40-75 F max): 0 - 100 F with 1 F scale divisions.

Condenser-Water Piping: 0 to 160 F with 2 F scale divisions.

Hot Water (120-180 F max): 30 - 240 F with 2 F scale divisions.

Steam and Steam-Condensate Piping: 50 to 400 F with 5 F scale divisions.

Conditioned Air Ducts: 0 to 160 F with 2 F scale divisions.

4.1.2.2.4 Thermowells

Standard: ASME B40.200.

Description: Pressure-tight, socket-type fitting made for insertion into piping tee fitting.

Material for Use with Copper Tubing: Brass

Material for Use with Steel Piping: Brass or Stainless Steel.

Bore: Diameter required to match thermometer bulb or stem.

Insertion Length: Length required to match thermometer bulb or stem.

Lagging Extension: Include on thermowells for insulated piping and tubing.

Bushings: For converting size of thermowell's internal screw thread to size of thermometer connection.

Heat-transfer compound: Shall be used to improve thermal transfer and to eliminate condensation forming within the thermowell. Compound shall consist of synthetic, efficient thermally conductive ceramic or metal oxides in a homogeneous, non-hardening paste with negligible bleed and evaporation loss. Compound shall not cause catalytic corrosion between probe material and thermowell).

4.1.2.2.5 Pressure / Temperature Test Plugs

Construct of brass, equip with NPT fitting, with self-sealing, dual valve core type Nordel gasketed orifice suitable for inserting 1/8" O.D. probe assembly from dial type insertion thermometer or pressure gauge. Test plugs shall be pressure rated for 500 psi and 275F. Equip orifice with gasketed screw cap and chain. Provide extension of length equal to insulation thickness for insulated piping.

4.1.2.2.6 Venturi Flowmeters:

Description: flowmeter assembly shall be commercial HVAC grade, venturi type, calibrated flow-measuring element including, hoses or tubing, fittings, valves, indicator, and conversion chart. All Venturi meters shall be manufactured under an ISO 9001:2000 certified quality program.

Flow Range: Sensor and indicator shall cover operating range of equipment or system served.

Sensor: low pressure loss venturi-type, calibrated, flow-measuring element; for installation in piping.

Design: Differential-pressure-type measurement for suitable for HVAC hydronic fluids, gases and steam.

The Venturi inlet section shall be cylindrical with a pressure sensing tap and of the same diameter as the incoming pipe section and followed by a precise smooth contoured radius section causing a uniform change in fluid velocity, and to maintain a low permanent low pressure loss.

Accuracy: shall be within ±2.0 uncalibrated (±0.5% calibrated) with a repeatability of ±0.1% and turndown of 10:1

Construction: Bronze, brass, or factory-primed steel, or as otherwise required to meet the intended service conditions if atypical, with extensions on sensing taps allowing for pipe insulation thickness and brass ball valve connections suitable for connection of tubing to flow indicating assembly.

Provide permanent, stainless steel tag with pipe size, manufacturer’s nameplate and flow conversion data on chain as required so that tag remains visible and not covered by insulation.

Minimum Pressure Rating: 250 psig or not less than 1.5 times maximum system working pressure, whichever is greater.

Minimum Temperature Rating: 250 deg F.

End Connections for 2” and Smaller: Threaded.

End Connections for 2-1/2” and Larger: Flanged or grooved.

Flow Range: Flow-measuring element and flowmeter shall cover operating range of equipment or system served.

Flow indicating assembly: Shall consist of:

Three valve manifold local direct reading gauge suitable for wall or bracket mounting, calibrated for connected flowmeter element, 4” min. diameter dial with threaded fittings

Scale: Gallons per minute (verify and coordinate any special requirements to adjust for use with glycol solutions).

Accuracy: Plus or minus 1 percent between 20 and 80 percent of scale range.

Additional P/T ports at each tap for local independent verification without disassembling tubing.

Copper tubing for connecting components together and to flowmeter taps.

Operation and Maintenance Data:

Conversion Chart: Flow rate data compatible with sensor. Include all data for each meter clearly recorded in Manual.

Operating Instructions: Include complete instructions with each flowmeter.

4.1.2.3 Execution

Install gauges and thermometers in locations where they are easily read from normal operating level.

Coil and conceal excess capillary on remote element instruments.

Pressure Gauges: Install pressure gauges with snubber in piping tee with pressure gauge valve(s), located on pipe at most readable position. Install siphon for steam pressure gauges. Extend nipples and siphons to allow clearance from insulation. Install pressure gauges in the following locations:

Inlet and Discharge of each pressure-reducing valve. One gauge on common inlet may be used for pressure reducing stations with multiple reducing valves.

Single gauge with isolation valves across inlet and outlet of each of the following:

Chiller chilled-water and condenser-water connection.

Hydronic heat exchangers.

Hydronic pumps.

Major strainers and filter housings (include adjustable set hands to indicate upper limit when service is required).

Exception: Individual gauges are permitted if length of tubing would be excessive or impractical for the preferred single gauge method.

Connection to expansion tank Single gauge with isolation valve manifold across supply and return at each piping system remote differential pressure sensor/transmitter (used to control VFD).

Thermometers: Install thermometers in the following locations:

Inlet and outlet of each hydronic boiler.

Inlets and outlets of each chiller (chilled water and condenser water supply and return).

Two inlets and two outlets of each hydronic heat exchanger.

Inlet and outlet of each hydronic zone (each secondary or tertiary loop with independent temperature control) Inlet and outlet of each hydronic coil in air-handling units.

Inlet and outlet of each thermal-storage tank.

Each inlet and outlet of air to air heat recovery device.

Outside-, return-, supply-, and mixed-air ducts.

Install thermometers in air duct systems on flanges.

Locate duct mounted thermometers minimum 10 feet downstream of mixing dampers, coils, or other devices.

Thermometer Wells: Install thermometers in piping systems in wells in short couplings.

Enlarge pipes smaller than 2-1/2 inch for installation of thermometer wells. Ensure wells allow clearance from insulation. Fill voids between thermowell and thermometer and BAS sensor stems with heat conducting compound before installing in wells.

Install pressure/temperature test plugs in piping tee, located on pipe at most accessible and readable position. Secure cap. Install where required to allow for balancing and troubleshooting without requiring permanent pressure gages and thermometers, including but not necessarily limited to the following locations:

Adjacent to all pressure or temperature BAS sensors in hydronic systems (for testing/calibration purposes).

At inlet and outlet of each hydronic terminal heat transfer device, such as:

air handling coils terminal heating and/or cooling units temperature control zones At each location where major return streams mix (for troubleshooting) In common pipe, approximately 10 pipe diameters downstream of mixing point.

In each upstream pipe section At inlet and outlet of each variable pressure change device, such as:

Strainers at minor/zone pumps and central air handling equipment coils. Not required at strainers of small terminal heating/cooling units.

Manual and automatic calibrated balancing valves (specify as manufacturer’s options factory fabricated on valves).

Adjust gages and thermometers to final angle, clean windows and lenses, and calibrate.

Adjusting: Adjust faces of meters and gauges to proper angle for best visibility.

For gauges on straining/filtering devices, adjust set hands on pressure gauges to accurately indicate when service is required (approximately 50% above pressure differential when clean (or as otherwise recommended by strainer/filter manufacturer).

After installation, zero and/or calibrate meters and gauges according to manufacturer's written instructions.

Cleaning: Clean windows of meters and gauges and factory-finished surfaces.

Replace cracked or broken windows, repair any scratched or marred surfaces with manufacturer's touch-up paint.

Venturi Flow Meters:

Assemble and install connections, tubing, and accessories between flow-measuring elements and flowmeters according to manufacturer's written instructions.

Install flowmeter elements in accessible positions in piping systems.

Install differential-pressure-type flowmeter elements, with at least minimum straight lengths of pipe, upstream and downstream from element according to manufacturer's written instructions.

Install permanent indicators on walls or brackets in accessible and readable positions.

Install connection fittings in accessible locations for attachment to portable indicators.

4.1.3 Testing Adjusting and Balancing

All testing and balancing shall be done in accordance with the National Environmental Balancing Bureau (NEBB) or Associated Air Balance Council (AABC).

On major construction projects, the balancing subcontractor must be certified by AABC or NEBB.

4.1.3.1 Procedures

The environmental systems including all equipment, apparatus and distribution systems shall be tested and balanced in accordance with the AABC or NEBB Procedural Standards.

Fume hood testing shall be in accord with the procedure outlined in the AABC manual.

All instruments used for measurements shall be accurate, and calibration histories for each instrument shall be available for examination. Calibration and maintenance of all instruments shall be in accordance with the requirements of AABC or NEBB.

Accuracy of measurements shall be in accordance with AABC or NEBB Standards.

During the operating tests of the chilled water system, provide, if necessary, a false load equal to full capacity on the chiller and submit data on gpm flow, pressure drop, inlet and outlet temperatures of chilled water, amperage of chiller and ambient air temperature at condenser.

In addition, the Contractor shall check the operation of all automatic temperature control equipment; verify all thermostat, aquastat, airstat, etc., set-points and operations; and enlist the aid of the control Subcontractor to make necessary adjustments where required.

4.1.3.2 Reports

Five copies of the final reports shall be submitted on applicable AABC or NEBB Reporting Forms for review and approval by TYAD.

Each individual final Reporting Form submitted must bear the signature of the person who recorded the data and the signature of the testing and balancing supervisor of the performing firm.

If more than one certified firm performs the TAB work, all final reports shall be submitted by that certified firm having managerial responsibility.

Identification of all types of instruments used and their last dates of calibration will be submitted with the final report.

The final test report shall include appropriate reference to all problems regarding the system(s) encountered prior to, during and after testing and what action taken to correct the problem(s), including noise and vibration.

Each report shall include a print, (or sketch) reduced in size, showing all supply, return, and exhaust air outlets for easy reference to report data.

An approved copy of the balancing report shall be included in the Maintenance Manual submittal.

4.1.3.3 Fan Sheaves

It is unacceptable for a balancing contractor to indicate that a system has been balanced as far as the existing sheaves permit. Change pulleys, belts, sheaves, etc., as required.

All adjustable sheaves shall be replaced with suitable fixed sheaves prior to final acceptance by TYAD.

4.2 HVAC Insulation

4.2.1 Fire Hazard Ratings

All insulation shall have composite (insulation jacket and adhesive used to adhere the jacket to the insulation) Fire and Smoke Hazard ratings as tested under procedure ASTM E-84, NFPA 225 and UL 723 not exceeding:

Flame Spread 25 Smoke Developed 50

Accessories such as adhesives, mastics, cements, and cloth for fittings shall have the same component ratings as listed above.

Paper laminate jackets shall be permanently fire and smoke resistant. Chemicals used for treating paper in jacket laminates shall not be water soluble and shall be unaffected by water and humidity. The only exceptions to the above are flexible foamed plastic insulation.

4.2.2 General

All pipe insulation shall be continuous through walls, partitions, ceiling openings and sleeves where fire and smoke ratings permit such penetration.

Where pipes pass through fire-rated floors, walls, or partitions, the use of a UL approved system for through penetrations is required. The annular space around the pipes shall be packed with mineral wool or other noncombustible material and sealed at each exposed edge to maintain the rating of the system in accordance with the through penetration sealant manufacturer's recommendations.

Insulation on all cold surfaces must be applied with a continuous, unbroken vapor seal.

Hangers, supports, anchors, etc., that are secured directly to cold surfaces must be adequately insulated and vapor sealed to prevent condensation.

Edges of vapor barrier insulation at valve stems, instrument wells, unions and other raw edges must be adequately sealed to prevent moisture from penetrating the insulation.

4.2.3 Insulation Protection Shields

Insulation protection shields fabricated from galvanized steel shall be installed at all pipe hangers and supports. Shields shall span an arc of 180°.

Provide shield lengths and thicknesses as outlined in the latest version of the International Mechanical Code.

Rigid cellular glass insulation, capable of resisting the crushing effect of the hydraulically loaded piping, shall be placed under each shield. Jacketing material shall be wrapped around rigid insulation and adjacent top and butt sections to maintain the jacketing continuity.

An 18 gauge stainless steel shield shall be installed on insulated piping located on the roof. The shield shall be a minimum length of 36 inches and field located to prevent damage to the insulation while walking over the piping.

4.2.4 Duct Insulation

Insulation systems shall conform to requirements in ASHRAE Standard 189.1 most current version.

The use of duct liner is discouraged. Duct liner may be considered for acoustical purposes only with the written approval of TYAD.

All duct insulation in mechanical rooms shall be rigid fiberglass board, minimum density 6 lb/ft3. All other duct insulation shall be blanket-type insulation wrapped on the outside of the ductwork.

4.2.5 Pipe Insulation

Insulation systems shall conform to requirements in ASHRAE Standard 189.1 most current version.

In general, refrigerant piping systems shall be insulated with elastomeric pipe insulation.

In general, all…