MAC 10 Original VE5 SERVICE MANUAL
PAGE 12
Note : When turning the unit “ON” from the “OFF” position of the speed control, the fan
is at the highest speed. Turning the speed control knob clockwise will lower the airflow.
VII. Trouble Shooting:
Low Air Velocity
Step 1.
Check prefilter media; replace or clean as necessary.
Step 2.
Flip switch from “Low” to “Medium” or “Medium” to “High” on units with 3-speed
switch.
Step 3.
Adjust variable speed control (only units with
optional
Speed Control) for
higher blower output.
Step 4.
Check power supply for proper voltage, amperage and distribution frequency.
Step 5.
Replace HEPA/ULPA filter if the air velocity remains low.
High Air Velocity
Step 1.
Flip switch from “HIGH” to “MEDUIM” to “LOW” on units with 3-speed switch.
Step 2.
Adjust variable speed control (only units with
optional
Speed Control) for lower
blower output.
Non-Laminar Flow and/or Excessive Contamination
Step 1.
Insure that no large obstructions are upstream of airflow pattern.
Step 2.
Determine that no other air-moving devices are operating in or around clean
room which disrupt room’s airflow pattern.
Step 3.
Check air velocity and if low, conduct the “Low Air Velocity” procedure outlined
above.
Step 4.
Conduct smoke and photometer test on HEPA filter. Seal or replace HEPA
filter as necessary.