4
6. Always round up to the next whole number. For example, if the minimum requirement is 2.1 units, 3
units are recommended, not 2.
Example 1:
How many 900 CFM units are needed to provide at least 6 ACH in a 25’ x 30’ x 10’ containment area, with a
20% safety factor?
V = 25 x 30 x 10 = 7,500 Cubic Feet
Total CFM = (7,500 x 6 x 1.2)
÷
60 = 900 CFM
Minimum # Units Req’d = 900 CFM
÷
900 CFM
(airflow of unit)
=
1 Unit Required
Example 2:
How many 900 CFM units are needed to provide at least 5 ACH in a 50’ x 42’ x 10’ containment area, with a
25% safety factor?
V = 50 x 42 x 10 = 21,000 Cubic Feet
Total CFM = (21,000 x 5 x 1.25)
÷
60 = 2,188 CFM
Minimum # Units = 2,188
÷
900 = 2.43 =
3 Units Required
Note: This example illustrates the importance of a Safety Factor. If no SF were used, only 1,750 CFM (2 units)
would be required.
PRED1200 TRANSPORT
Note
: The PRED1200 can be transported in the horizontal position. If extremely poor road conditions exist, or
excessive shock and vibration are expected, take precautionary measures by padding the unit to provide impact
absorption during transport.
Caution
: Always use caution when moving the PRED1200 inside a building or home. The unit weighs 70
pounds. Older structures with weakened floors or staircases may require special considerations for safe transport.
ELECTRICAL REQUIREMENTS
1. The PRED1200 requires a minimum of 110 volts AC, 60 Hz to operate properly; however, maximum airflow
performance requires 120 volts AC, 60 Hz.
2. Due to momentary start-up current surge, the unit requires a 15 amp circuit that is free of other loads.
3. Extension cords used for the PRED1200 must be UL-listed, heavy duty No. 14/3 AWG industrial grade 3-
wire type. Use of larger numerical gauge (lower capacity wire) power cord(s) may result in electrical shock,
fire hazards and/or damage to unit. The cord(s) must be in good condition and in continuous lengths (no
splicing) and should not exceed a total of 50 feet in length. Make certain that any extension cords used do
not reduce power to the unit to less than 110 volts. Use of a voltmeter to confirm adequate voltage is
recommended.
4. Check to ensure that any circuit to which the unit is connected is protected by a 15 ampere circuit breaker.
The unit itself is equipped with a 12 amp circuit breaker.
5. The PRED1200 should be connected to a three-prong, properly grounded electrical outlet equipped with a
Ground Fault Circuit Interrupt (GFCI) device. A GFCI is an electrical safety device that will trip the circuit and
stop the flow of electricity if leakage of current is detected.
Important Note: The GFCI on the PRED1200 control panel only detects leakage of current from the
unit or an electrical device plugged into the GFCI. The PRED1200 should be plugged into a GFCI
receptacle at the power source to protect the power cord and the unit. This GFCI will trip the
circuit if it detects leakage of current from the power cord or unit.
6. To avoid personal injury, fire hazards and/or damage to the PRED1200 electrical system and power cord,
do not connect or disconnect the power cord to an electrical outlet unless the motorized impeller is “OFF”.
