H39.REV

BALANCING AIR AND WATER SYSTEMS

NOTE: FINAL COPY: JANUARY, 1987.

Part 1 -	GENERAL

1)	WORK INCLUDED

A.	Work in this Section includes the providing of labor, materials, equipment, and services necessary for complete balancing and adjusting of all heating, ventilating and air conditioning systems in accordance with the contract documents and all applicable codes and authorities having jurisdiction for the following

NOTE: EDIT AS REQUIRED.

1.	Operational testing of central station and air handling equipment

2.	Balancing of air distribution systems.

3.	Adjustment of air terminal devices for HVAC systems.

4.	Flow testing and balancing of hydronic systems.

5.	Furnishing instruments required for testing, adjusting and balancing operations and making instruments available to Architect/Engineer to facilitate spot checks during testing. Retain possession of instruments and remove from site at completion of services

6.	Recording flow of existing air and water systems which are to remain and rebalancing of these systems

2)	RELATED WORK AND REQUIREMENTS

A.	Requirements of GENERAL CONDITIONS, DIVISION NO. 1 and Section GENERAL PROVISIONS FOR HEATING, VENTILATING AND AIR CONDITIONING WORK apply to all work in this Section

NOTE: EDIT TO SUIT PROJECT REQUIREMENTS. INCLUDE ONLY SECTIONS DIRECTLY AFFECTING WORK OF THIS SECTION

B.	Related work in following sections:

1.	PIPING.

2.	STEAM SYSTEM.

3.	CHILLED WATER SYSTEM.

4.	HOT WATER SYSTEM.

5.	FAN COIL SYSTEM.

6.	BOILER PLANT - GAS FIRED (less than 2000 MBH).

7.	BOILER PLANT - #2 OIL FIRED (less than 2000 MBH).

8.	HOT WATER BOILER PLANT (larger than 2000 MBH).

9.	STEAM BOILER PLANT (larger than 2000 MBH).

10.	REFRIGERATION PLANT (Centrifugal Units).

11.	PACKAGED RECIPROCATING WATER CHILLERS (Water Cooled).

12.	CONDENSER WATER SYSTEM (Packaged Cooling Towers).

13.	CONDENSER WATER SYSTEM (Field Assembled Towers).

14.	PACKAGED AIR-COOLED WATER CHILLERS (Reciprocating or Centrifugal)

15.	SELF-CONTAINED COMPUTER ROOM AIR CONDITIONERS.

16.	PACKAGED ROOF-TOP UNITS.

17.	HEAT PUMPS.

18.	AIR COOLED CONDENSER SYSTEM (For Split DX System).

19.	EVAPORATIVE CONDENSER SYSTEM (For Split DX System).

20.	AIR HANDLING SYSTEM EQUIPMENT.

21.	AIR DISTRIBUTION SYSTEM EQUIPMENT.

22.	MECHANICAL VENTILATING SYSTEMS.

23.	AUTOMATIC CONTROL SYSTEMS.

24.	THERMOMETERS, GAUGES AND RECORDING INSTRUMENTS.

25.	-----.

3)	REFERENCE STANDARDS

A.	Published Specifications' standards, tests or recommended methods of trade, industry or governmental organizations apply to work in this Section

B.	Unless otherwise indicated, all systems shall be balanced and adjusted in accordance with AABC - Associated Air Balance Council, NEBB - National Environmental Balance Bureau and SMACNA - Sheet Metal and Air Conditioning Contractors' National Association, Inc

C.	Comply with all applicable national, state and local codes and refer to Section GENERAL PROVISIONS FOR HEATING, VENTILATING AND AIR CONDITIONING WORK for additional Reference Standards

4)	QUALITY ASSURANCE

A.	Prior to start of testing, adjusting and balancing, verify that the systems installation is complete and in full operation. Verify that outside conditions are within reasonable range relative to design conditions and that doors and windows are in place or under normal traffic conditions. Ensure that lights are turned "on" for cooling load checks and are turned "off" for heating load checks

NOTE: INCLUDE, AS APPLICABLE FOR THIS PROJECT, NEXT 2 ITEMS.

1.	Ensure that special equipment such as computers, laboratory equipment, and electronic equipment are in full operation

2.	Dummy loads: When operation testing is performed before final computer, laboratory and other equipment are installed, provide temporary electric heat loads in rooms, at no extra cost to Owner. Capacity of heating devices shall be such as to equal full heat gain in rooms, with exact capacity and location as directed by the Architect. Provide heating devices, wiring, connecting fittings compatible with electric circuits, operating and safety controls and other devices, as required. Other heating mediums than electrical may be proposed for approval by Architect and/or Engineer

B.	Verify that requirements for preparation for testing and balancing have been met for elements of each of the systems which require testing

C.	End result of balancing of air systems shall be satisfactory relationship of air pressures, flow directions, room temperatures, etc., whether quantitive data on drawings result in these conditions or not. Make measurements and adjustments in addition to drawing indications if necessary to result in satisfactory air balance. Building air balance shall comprehend overall balance between all systems, whether or not drawing figures may have to be modified to achieve overall balance

D.	Make air balance measurements and adjustments for multiple operating conditions where areas are subject to variety of circumstances (doors open and/or shut, etc.)

NOTE: VERIFY THAT FULL PROVISIONS FOR PREPARATION OF EACH SYSTEM ARE SPECIFIED FOR EACH OF THE RESPECTIVE SYSTEMS

5)	SUBMITTALS

NOTE: EDIT TO SUIT PROJECT REQUIREMENTS.

A.	Furnish to Architect and/or Engineer documentation that the Air Balance Company is a member of the Associated Air Balance Council, or National Environmental Balancing Bureau and that it has satisfactorily balanced at least three systems of comparable type and size. Include list of such projects. Sample forms for use in compiling and recording test and balance data shall also be submitted

B.	Final submission shall include records and tabulations required hereinafter and certified by a registered professional mechanical engineer experienced in balancing HVAC systems.

C.	At least fifteen (15) days prior to starting field work, submit three (3) copies of report forms filled out, including design flow values, installed equipment pressure drops and required CFM for air terminals. Submit a complete list of instruments proposed to be used, organize in appropriate categories and include data sheets for each. Indicate each manufacturer and model number, description and use when needed to further identify instrument, size or capacity range and latest calibration date

1.	Architect/Engineer will review submittals for compliance with Contract Documents, and will return one set marked to indicate discrepancies noted between data shown and Contract Documents, additional, or more accurate, instruments required and requests for re-calibration of specific instruments

2.	Submit proposed method of balancing variable air volume systems to account for system diversity

D.	At least fifteen (15) days prior to Contractor's request for final inspection, submit three (3) copies of final reports, on applicable reporting forms, for review

1.	Schedule testing and balancing of parts of systems which are delayed due to seasonal, climatic, occupancy, or other conditions beyond control of Contractor, as early as proper conditions will allow, after consultation with the Architect and/or Engineer

2.	Submit reports of delayed testing promptly after exection of those services

3.	Each individual final reporting form must bear the signature of the person who recorded data and the signature of the Registered Professional Engineer Supervising air balance of the reporting organization

a.	When more than one certified organization performs total air balance services, the firm having managerial responsibility shall make submittals

b.	Identify the instruments of all types which were used, and the last date of calibration of each

REV

6)	PROJECT REVIEW

A.	Perform detailed pre-construction plan check and construction review

B.	Refer to AABC National Standards, latest Edition.

7)	PROJECT REVIEW

A.	Pre-Construction Review.

1.	Review Contract Documents (drawings, specifications, bulletin, addenda), submittal data, shop drawings and automatic temperature control drawings

2.	Assure that design intent is clearly understood. Identify potential problems from standpoint of total system balance

3.	Review specifications for scope of work, special requirements and items that will make balancing difficult or impossible

4.	Review drawings for potential problems for total system balance, including location of balancing devices, lack of balancing devices, general system layout, architectural features and accessibility. Determine the most effective system balancing procedures and determine scheduling and coordination requirements

5.	Review submittal data for completeness of data, conformity with Contract Documents, special instructions for use of balancing devices, factors for flow meters, limitations affecting accuracy of measurements and equipment performance data and curves

6.	Review shop drawings for potential problems for total system balance, as specified above for review of Contract Drawings

7.	Review automatic temperature control drawings for thorough understanding of system functions and determining the most effective total system balancing procedure for minimum control manipulation. Avoid disturbing calibration of control devices and coordinate required control manipulation with Control Contractor

8.	Submit report recommending addition and/or relocation of balancing devices, including, but not limited to, volume dampers, balancing valves, flow metering devices for air and water, and pressure and temperature measuring points

B.	Construction Review: make on-site visits during progress of construction. Number of visits shall be as required to perform the functions specified below

1.	The purpose of the review is to identify potential problems for performing total system balance. Identify modification which will affect total system balance. Schedule and coordinate total system balance with other work. Identify conditions that could create hazardous environment for building occupants

2.	Typical activities: check that necessary balancing and measuring hardware are located properly, are accessible and installed correctly. Identify and evaluate variations from system design. Record data from equipment nameplates. Identify and report possible restrictions in systems, such as closed fire dampers, long runs of flexible duct, poorly designed duct fittings, questionable piping connections and others. Verify that construction progress will not delay total system balance. Identify best location for duct pitot tube traverses. Identify scaffolding needs

REV

Part 2 -	PRODUCTS

1)	GENERAL

A.	Products and materials shall be as described in pertinent Sections of DIVISION NO. 15

Part 3 -	EXECUTION

NOTE: INCLUDE AS APPLICABLE FOR THIS PROJECT.

1)	AIR SYSTEM BALANCING:

A.	Check that filters are installed clean and free of bypass, and are the type as specified. Make allowance for air filter resistance at time of tests. At design air quantity, the pressure drop across filter banks should be midway between the drops for clean and dirty filters. Submit written report that above was done

B.	In cooperation with the automatic control manufacturer, set adjustments of automatically operated dampers and air terminal boxes to operate as indicated. In cooperation with the automatic control manufacturer and the terminal box manufacturer, verify factory setting of air terminal boxes. Make adjustments required to produce design conditions. Submit written verification that all items listed above have been completed

C.	Fan testing: test and adjust fans speed to design requirements and test and record motors full load amperes

D.	Duct testing: make pitot tube traverse of main supply ducts and obtain design air quantities (cfm) at fans. Adjust main supply, return, and exhaust air ducts to proper design cfm. Adjust each zone supply, return and exhaust to proper design cfm's. Test and adjust recirculated air systems for design cfm's. Test and adjust outside air systems for design cfm's. Test and record suction and discharge systems' static pressures

E.	Air outlet balancing: test and adjust each diffuser, grille and register to within 5 percent of design requirements. Identify each grille, diffuser and register as to location size, type and manufacturer and submit in recorded tabulation with floor plan. Readings and tests of diffusers, grilles and registers shall include required velocity (fpm), test resultant velocity, required cfm, test resultant cfm after adjustments; all in accordance with manufacturers' ratings. Adjust diffusers, throw pattern, grilles and registers to minimize drafts. When balancing return air slots in lights, start with all slots open, and close down dampers as required nearest to return/exhaust air intakes above ceiling

F.	Record in tabulated form balance data by clearly identifying floors, zones, rooms and air outlet/inlet locations to correspond to those in the Contract Documents

G.	Temperature conditions; read and record the following:

1.	Outside climatic conditions at time of testing, including DB and WB temperatures and whether it is sunny, cloudy, windy, etc

2.	Entering DB heating and cooling temperature.

3.	Entering WB cooling temperature.

4.	Leaving DB heating and cooling temperature.

5.	Leaving WB cooling temperature.

6.	DB temperature and velocity in occupied zones.

H.	Sound level readings: take sound level readings at one or more diffusers in each zone approximately 5 feet above the floor. The allowable room sound-pressure level shall fall within range of specified allowable sound power level in the area. See Section Noise Control for the requirements

DB

1.	33 to 37 db.

2.	(Specify other range, with list of rooms.)

DB

I.	Belt drive changes: make all changes in belts and sheaves required to obtain proper air balance

NOTE: SELECT APPLICABLE OPTION FROM THE FOLLOWING LISTINGS. OPTION 1 IS THE MOST COMMON APPROACH BUT OPTION 2 BENEFITS THE OWNER BECAUSE THE CONTRACTOR NEED NOT GAMBLE ON HOW MUCH TO PUT IN HIS BID FOR DRIVE CHANGES. IT SHOULD RESULT IN MORE EVEN BIDS. COORDINATE WITH ARCHITECT HOW THE CHANGE ORDER WILL BE HANDLED AND EDIT THE PARAGRAPH AS REQUIRED

COST

1.	At no extra cost to Owner.

2.	At end of project, submit an accounting of the costs of additional drives. Upon approval of Architect and/or Engineer, these costs form part of change order to contract. Base accounting is based upon replaced drive material list price times a factor of 2.5 (or other rate as determined by Architect and/or Engineer)

COST

NOTE: INCLUDE IF APPLICABLE FOR THIS PROJECT.

J.	Fume Hood Test and Balance: test each fume hood, of any type, and associated exhaust system in accordance with National Standards of AABC, latest Edition. Procedure shall include, but not be limited to, determining and adjusting exhaust flow rate, determining and adjusting face velocity across hood face or opening, determining and adjusting make-up air conditions and determining and adjusting spillage conditions at hood opening

1.	Special tests shall include perchloric acid washdown system, special filter systems and others as required.

2.	Demonstrate that associated controls and electrical interlocks perform as specified. Submit test report in accordance with AABC National Standards

3.	Special filter systems for hoods shall be tested for proper operation and adjusted to maintain constant air flow through the system regardless of filter resistance. Flow shall be tested under not less than five different resistances representating clean, 25%, 50%, 75% and 100% dirt loading. Variations in airflow shall not be sufficient to adversely effect hood performance

4.	Test all fume hood systems in conjuction with the associated auxiliary air, supply air and exhaust air systems as required

5.	Submit the test report in accordance with AABC National Standard, Chapter 23.4

6.	Hood certification: provide AABC certificate for each hood and place in conspicuous location

NOTE: INCLUDE AS APPLICABLE FOR THIS PROJECT.

2)	WATER SYSTEMS BALANCING:

A.	Provide the following instruments for field use:

1.	One set of pressure gauges and fittings.

2.	Dry bulb thermometer.

3.	Wet bulb thermometer.

4.	Thermocouple unit and thermocouples.

5.	Set of balancing cock adjustment wrenches.

6.	Portable field flowmeter; deliver to Owner at completion of work

B.	Prepare water systems for balancing in the following manner and verify that the following conditions

1.	Piping systems have been flushed and treated in accordance with Section "PIPING" and Section "WATER TREATMENT"

a.	Strainers have been cleaned.

b.	Insides of traps, reducer and regulating valves have been cleaned

c.	Expansion tanks are not air bound.

d.	Piping systems are completely full of water.

e.	Water systems are not air bound and that air vents are installed and operating properly

2.	Open normally open valves to full-open position. Verify that normally closed valves are closed

3.	Check pumps' rotations and check operation of automatic valves

4.	Set automatic controls so all coils are calling for:

a.	Full cooling: when balancing chilled water coils

b.	Full heating: when balancing hot water coils.

c.	When balancing heat recovery coils, set for either heating or cooling or make settings for both conditions

NOTE: INCLUDE ITEMS ONLY AS APPLICABLE FOR THIS PROJECT.

5.	Check and set operating temperatures to design requirements for boilers, heat exchangers, chillers, cooling towers (and others as required)

6.	Check and set operating temperatures of secondary and primary systems. Accomplish complete air balance before actual water balance begins

7.	Submit written verification that items listed above have been completed

NOTE: INCLUDE ITEMS ONLY AS APPLICABLE FOR THIS PROJECT.

C.	Initial adjustments: Set chilled water, condenser water and hot water pumps to proper gpm delivery. Adjust water flow through boilers, heat exchangers, chillers, cooling towers (and others as required)

1.	Check leaving water temperatures and return water temperatures through chillers, boilers, heat exchangers, cooling towers (and others as required)

2.	Check water temperature at inlet side of cooling and heating coils. Note rise or drop of temperature from source

3.	Proceed to balance each chilled and hot water coil. Upon completion of flow reading and adjustments at coils, mark all settings and record all data

4.	Proceed in same way to balance run-around heat recovery system

D.	Refrigeration machines:

NOTE: WATER COOLED REFRIGERATION MACHINE IS SPECIFIED. DELETE REFERENCES TO CONDENSER WHEN AIR COOLED REFRIEGERATION MACHINE IS USED

1.	Verify flow rates through chiller and condenser using metering device compatible with venturi flow units provided. Take the following readings for each machine

a.	Inlet and outlet chilled and condenser water temperatures

b.	Inlet and outlet chilled and condenser water pressures

c.	Chilled and condenser water gpm.

d.	Evaporator temperature and pressure.

e.	Condensing temperature and pressure.

E.	Provide detailed balance upon completion of preparation and adjustments and proceed as follows: after adjustments to coils are made, recheck and readjust as required settings at pumps, boilers, heat exchangers and chillers

1.	Record and check the following items:

a.	Inlet water temperature to coils.

b.	Leaving water temperature (each coil in multiple coil banks)

c.	Pressure drop (each coil in multiple coil banks)

d.	Each pump operating suction and discharge head.

e.	List mechanical specifications of pumps.

f.	Rated and actual running amperage of pump motor

F.	Final tabulation: perform operational test including all component systems of air conditioning system in the presence of Architect's and/or Engineer's representative. After balancing air conditioning components, put entire system into operation. Record all pressures, temperatures, gpm's, velocities, etc. Check recorded data against design schedules. Include approved test reports in "Operating Instructions" and submit as specified under Section "GENERAL PROVISIONS FOR HEATING, VENTILATING AND AIR CONDITIONING WORK"

3)	CONTROL COORDINATION

A.	Cooperate with automatic control installer and equipment installer in making adjustments to following items as required to accomplish indicated performance, including terminal air boxes, air valves, fan inlet vanes and adjustable and controllable pitch fan blades

NOTE: INCLUDE AS APPLICABLE FOR THIS PROJECT ANY OTHER ITEMS.

NOTE: THE FOLLOWING PARAGRAPH SHOULD BE USED ON REMODELING PROJECTS WHERE PART OF THE EXISTING AIR DISTRIBUTION SYSTEM IS INTENDED TO REMAIN CONNECTED TO THE NEW SYSTEM PROVIDED AS PART OF THE REMODELING WORK. THE INTENT IS TO RECORD THE AIR FLOW PRIOR TO MODIFYING THE SYSTEM SO THAT AFTER THE COMPLETION OF THE REMODELING WORK, THE ENTIRE SYSTEM CAN BE BALANCED TO SUPPLY THE SAME AMOUNT OF AIR TO THE EXISTING PORTION. THIS AVOIDS THE PROBLEM OF ATTEMPTING TO DETERMINE WHAT AIR QUANTITY SHOULD BE USED AND NOT RELYING ON OLD DESIGN OR AS-BUILT DRAWINGS WHICH MAY NOT BE ACCURATE

4)	RECORD OF EXISTING AIR FLOW

A.	Prior to demolition of existing work, measure and record existing air flows in main supply, return and exhaust ducts. Make pitot tube traverse in sections of existing ducts which are to remain, or as near as practicable. Use these recorded measurements to re-balance existing duct systems after completion of new systems

NOTE: THE FOLLOWING PARAGRAPH SHOULD BE USED ON REMODELING PROJECTS WHERE EXISTING CIRCULATING WATER SYSTEMS REMAIN CONNECTED TO THE NEW SYSTEM PROVIDED AS PART OF THE REMODELING WORK. THE INTENT IS TO RECORD THE FLOWS PRIOR TO MODIFYING THE SYSTEM SO THAT AFTER THE COMPLETION OF THE REMODELING WORK, THE ENTIRE SYSTEM CAN BE BALANCED TO SUPPLY THE SAME WATER FLOW TO THE EXISTING PORTION. THIS AVOIDS THE PROBLEM OF ATTEMPTING TO DETERMINE WHAT WATER FLOW RATES SHOULD BE USED AND NOT RELYING ON OLD DESIGN OR AS-BUILT DRAWINGS WHICH MAY NOT BE ACCURATE

5)	RECORD OF EXISTING WATER FLOW RATES

NOTE: SPECIFY OTHERS AS REQUIRED.

A.	Prior to demolition of existing work, measure and record existing flow rates in chilled water, heating water and condenser water

B.	Procedure: make flow meter readings. Where no flow meters are installed in existing systems, measure and record differential pressures across pumps, coils, heat exchangers, and differential temperatures across coils, heat exchangers, boilers, chillers, cooling towers, etc. In sections of existing piping systems which are to remain, or as near as practicable, use these recorded measurements to re-balance existing water systems after completion of new systems