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Desert Aire - LC/LV Manual
Figure 22 - Approximating Outdoor Air CFM
OA
CFM
= LA
CFM
x (LA
TEMP
– RA
TEMP
) / (OA
TEMP
– RA
TEMP
)
LA
TEMP
= (OA
CFM
x (OA
TEMP
– RA
TEMP
) / LA
CFM
) + RA
TEMP
NOTE:
•
This method is just an approximation! In applications where strict code
compliance is required, proper airflow must be determined by a professional
testing and balancing contractor.
•
Refrigeration circuit must remain inactive during this procedure (blower on
only).
•
When measuring air temperatures, several readings must be taken across a
duct
and
averaged.
•
Proper LA
CFM
(total system airflow) must be confirmed prior to this
procedure. This is done by achieving specified airflow pressure drop across
the reheat coil. See section 3.3 for details.
EXAMPLE 1:
Determine how much OA
CFM
is entering an LC05
Measured:
LA
CFM
= 2300, LA
TEMP
= 73°F, RA
TEMP
= 82°F, OA
TEMP
= 40°F
Solution: OA
CFM
= 2300 x (73°F – 82°F) / (40°F – 82°F) = 490 CFM
3.3 Airflow Balancing
To ensure code compliance and long equipment service life, proper airflow must be verified by
a qualified air balancer. Shut off the compressor to prevent the refrigeration system from
running while you balance the air.
3.3.1 Blower Adjustment Procedure
Warning! Disconnect Power to the Unit before you adjust the Blowers.
Summary of Contents for ExpertAire LC Series
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