Evaporator Fan Adjustment - LG LK-0580CC Instrucciones De Instalación Y Mantenimiento

13. Evaporator Fan Adjustment

Use the following procedure to determine the proper adjustment of the evaporator fan for a specific application.
1. Determine total system external static pressure (in inches water column) with accessories installed. to accomplish
this:
1) Obtain the design airflow rate and the design external static pressure drop through the distribution system. Your
sales representative or the design engineer can provide you with these values.
2) Using the table from unit Service Manual, add static pressure drop of the accessories installed on the unit.
3) Add the total accessory static pressure drop (from step 1b) to the design external static pressure. The sum of
these two values is the total system external static pressure.
2. Use the table(s) in the Service Manual to find the external static pressure (in inches water column) that most
closely approximates total system external static pressure. Then locate the appropriate airflow rate (on cfm) for
your unit. The value obtained represents the break horsepower for the evaporator fan motor and the fan RPM.
Important: Fan Break Horsepower (BHP) listed in the Table is the percentage range of nameplate
amperage the motors will safely work within, before an oversized motor is required.
On the below 5.0RT model indoor fan motor is shipped to operate in High speed cooling and heating. It can be
rewired to operate in Low or super Hi speed cooling and heating. See wiring diagram in the unit how to rewire.
On the above 6.25RT models, the indoor fan speed is changed by opening or closing the adjustable motor sheave.
See Figure 8.
To Increase CFM
Loosen the pulley adjustment set screw and turn sheave clockwise.
To Decrease CFM
Loosen the pulley adjustment set screw and turn sheave
counterclockwise.
Note: The actual external static pressure may varies from
design ESP due to actual duct work installation.
The required air flow should be respected to provide
the design cooling capacity.
To Increase Belt Tension
• 6.25RT ~ 15RT
1) Loosen adjustment bolt.
2) Pull motor mounting plate back until belt is tight.
3) Tighten adjustment bolt after belt has correct tension.
FORCE(F) HEIGHT(S)
9~11 lbf 0.8 ~ 1.2(inch)
REMARK
-
19
Adjustment bolt
Figure 8A
F
S