CAMP LEJEUNE, NORTH CAROLINA - Senate Judiciary Committee

factor prescribed by the man(Jfactnrer for u.re in
conJunclion wilh a pnrlicHlar Inslrumenle In addilion
il is often necessn thai Ihe rending !
grilles, regislers nnd dillusers bn Inkon in a
posilion or number of positions prescribed by
Ihe manulaclurer of lhe air lerminal device.
9) Repeal Ihe branch bnlmcing unlil Iho system is
in balance.
10) Verify Ihe fan cnpacily nnd operating con(lilion
again and make a final adjuslmenl in the fan
ddve If necessaw.
11) Veri Ihe action of all fnn shul down conlrols
and aldlow safely conlrols.
12) Prepare all TAB reporl forms and sbmil as
required, using Ihe NEBB TAB Repeat Forms
SYSTEMS WitH
ECONOMIZERS
Follow Ihe procedures oullined for exhausl and relurn
air syslems, excepl Ihal allot balancing Ihe relure
air syslem and tile associaled supply air syslem
Ihe relurn air damper should be closed; Ihe inletlocked
relief air damper should be opened and the
relurn air fan, slalic pressure and clm should be
checked again. If il is necessary to increase tile system
static pressure and Ihereby reduce tile fan cfm,
adjust lhe exhausl air damper 1o a maximum position
less Ihan 100% open. Recheck lhe supply fan airflow
with Ihe oulside air damper In Ihe full open position.
OPTIONAL PROCEDURE
RATIO METHOD
This Is one of the olher melhods Ihal has been developed
for Ihe final balancing process.
1) Do all of tile TAB work un(ler Sul)-oecliofl A of
tills section entitled "Basic Air System Procedures."
2) Then begin balancing Ihe supply syslem al Ihe
las! outlet of Ihe branch lmlhest from lhe fan
(branch number 1). This is oullel number 1,
number 2 is Ihe next Io lhe last oullel. Measure
Ihe airflow al oullel number (Q,.) and compare
wilh tile design airflow for Ihat oullet (Q,), recold
the ratio (Q,./Qd).
3) Measf=re Ihe airflow al outlet number 2 and
delormine Ihe ratio (QJ(3d). Compare
mid (Q/Q,),. If Ihese rations are eel Wilhln 10%
of each olher, adjust oullel number 2 1o bring
ratios Inlo closer agreement. DO NOT ADJUST
OIITI ET NUMBER 1.
Measme and again determine (Q,./Q,)= and
(Q,,,/Q,), and compare. If lhese are wilhin 10%
of each olher, no further adjuslmenl is necessary.
Proceed to oullel number 3.
4) Delermlne (Q.,/Qd)= and compare with (Q,,J
Q.). If necessary, adjust number 3 so that
(O,,,IOe) end (Q,./O,)=’db not vary by more Ihari
10%. DO NOT ADJUST OUTLETS 1 OR.2.
(Adjushnonl of oullel 3 aulomalically changes
the (Q,JOe) ratios of oullets 2 and 1. The ratios
for all Ihese oullel9 approach lhe same values.
For this reason, once Ihe oullel has been adjusled,
il does eel require fudher adjustment).
5) Proceed to oullel number 4 and adjusl Io oblain
nflmemenl between (Q.,IQ) and (Q,.IQe)=.
6) Aller all oullels on branch number are propoHionalely
balanced to each olher, proceed Io
branch number 2, elc.
Upon complelion of propodionate balancing of
all outlets, the branches should .be propoHionalely
balanced.
7) Select typical oullels in branches 1 and 2 ..."
djusl number 2 branch damper Io obtain
agreement of Ihe (Q,./Qe) ratios for Ihe two
branches. Proceed in like manner to obtain
agreemenl between bran;hes 2 and 3, 3 and 4,
elc.
8) Upon completion of proportionate balancing,
recheck Ihe fan,capacily. Adjust Ihe fan.speed
to obtain a (Q,./Q.) ratio of 1.0 al the fan. Since
the system has. been propodtonately adjusted,
lhe ((.),,JO,) ratio Ihroughogt the system will be
approximately 1.0 and lhe flow from each outlet
will be Ihe design airflow rale.
9) Then continue lhe TAB work by following all of
the steps lisled under Sub-Section B--"Supply
Air Syslems Procedures" found earlier in this
section.