Gentek 3940202 User Manual

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Chapter 6: Maintaining Your Filtered Enclosure

How to Install a New HEPA Filter with the Bag-In/Bag-OutProcedure for XPert Filtered Balance Systems and Stations

The XPert enclosures include a true bag-in/bag-outfilter disposal system for safely removing the HEPA filter and protect the worker from toxic powders and particulates. See Figures6-1for the Bag-In/Bag-OutProcedure. For your safety, wear appropriate personal protective equipment during the change of HEPA filters. If working with biohazardous materials, use the decontamination procedure outlined in Chapter 6. (Consult your Safety Officer before performing filter changes).

1.With the enclosure OFF, remove the front panel secured by two screws on top of the enclosure.

2.Remove the bungee cords and retaining strap on the bag and extend it out. The retaining strap provides an extra level of safety even though the enclosure is under negative pressure when the blower is on.

3.Loosen the two filter clamp bolts with a 9/16" socket securing the HEPA filter. See Figure 4-1and4-2.

4.Place both arms in the rear gloves of the bag, and carefully draw the HEPA filter out of the enclosure. Rest the HEPA filter on the floor, table or cart. Remove arms from bag gloves.

5.Create two seals between the enclosure bag access port and the old HEPA filter. Seals can be heat sealed or sealed with tie wraps. Cut off the bag between the two seals and leave the bag stub on the access port to the enclosure.

6.Place the new HEPA filter in the new bag. Then place the new bag and new HEPA filter over the old bag stub and onto the enclosure access port.

7.Carefully remove the old bag stub using the single glove near the access port. Reattach the retaining strap on the perimeter of the new bag at the enclosure access port.

Draw the old bag stub into the single glove and turn the glove inside out. Double seal this glove and cut off the glove with the contaminated bag stub inside.

8.Carefully install the new HEPA filter and uniformly tighten the two filter clamp bolts until the HEPA filter gasket is compressed 50%.


Chapter 6: Maintaining Your Filtered Enclosure

9.Carefully fold and roll the new bag in four-inchpleats and push the bag into the access port. Reinstall the retaining strap and bungee cords. Turn the enclosure ON to draw a vacuum on the bag. Reinstall the front panel.

Figure 6-1

Bag-In-Bag-OutHEPA Filter Changing Procedure Diagram &

Filter Leak Test Diagram

HEPA Filter Leak Test


After installing the new HEPA filter, the HEPA filter should be leak checked. This test is performed to determine the integrity of the HEPA filter, the filter housing, and the filter mounting frames. Leak testing is to be done by a qualified technician with calibrated equipment. Remove the top perforated exhaust cover by using a Phillips screwdriver to unfasten the (2) screws used to secure (2) clips. See Figure 6-1.The filter passes the leak test at .01% or better. Reference Leak Testing and Photometer scanning from the Institute of Environmental Services(IES-RP-CC001.3)



Chapter 6: Maintaining Your Filtered Enclosure


1.An aerosol photometer ATI model 2D, 2E, 2G or equivalent. Air Techniques Hamilton Associates inc. 11403 Cron Ridge Dr. Owings Mills, MD 21117

2.One aerosol generator of the Laskin nozzle(s) type. An aerosol of mineral oil or suitable liquid shall be created by flowing air through it. The compressed air supplied to the generator should be adjusted to a pressure of 10± 1 psig. during operation. Air Techniques Inc. Model TDA-4A or equal. One nozzle at 10 psig is (67.5 cfm x 100ug/l)/(Vol. of air), For the 2' at 90 fpm or 130 cfm, one nozzle @10 psig is 13,500/130 cfm = 52 ug/l. For the 3' at 90 fpm or 200 cfm, one nozzle @ 10 psig is 34 ug/l. For the 4' at 90 fpm or 265 cfm, one nozzle at 10 psig is 26 ug/l.

3.Mineral oil (Catalog #1491400).

4.Sampling Nozzle, Rectangular 1/2" x 3-1/4", Air Techniques, Inc.


For the ATI 2G Photometer

1.Turn on the photometer and allow it to operate for a minimum of 5 minutes. Leave the valve in the “CLEAR” setting.

2.Press the “ENTER” keypad. Press the “REF” keypad.

3.The display will display “P1” for approximately 1 second, and then display a numerical value.

4.Using the “^” or “ν” keypads, respectively, increase or decrease the numerical value until it equals 52 (2'), 34 (3'). 26 (4') for the enclosure at 90 fpm inflow velocity.

5.Press the “ENTER” Keypad. The photometer will scan for 15 seconds, and then the “0” keypad will flash. Press the “Enter” keypad. The unit will scan for 5 seconds, the display will read “0000,” and the unit will sound a confirming tone.

6.Set the valve to “DOWNSTREAM.” Place the palm of your hand over the sampling port of the pistol. There should be a strong vacuum at this port. If the vacuum is weak, contact Air Techniques Hamilton Associates.

7.Turn the enclosure on and let it operate for a minimum of 5 minutes.


Chapter 6: Maintaining Your Filtered Enclosure

8.If necessary, adjust the speed control of the enclosure to maintain the following airflows at 90 fpm; 2' (130cfm), 3' (200 cfm, 4' (265 cfm.)

9.Position the aerosol generator discharge in the intake of the baffle inside the enclosure.

10.Start the aerosol generator (Pressure to be +/- 1 PSIG). Ensure that one Laskin nozzle is in the “open” position.

11.Allow the generator to operate for a minimum of 15 seconds. For all integral motorized impeller models, scan the downstream exhaust side of the HEPA filter by passing the sampling nozzle of the gun in slightly overlapping strokes over the entire surface the filter, with the sampling port not more than 1 inch from the surface of the filter media. Scan the entire periphery of the filter and the gasket between the filter frame and the enclosure frame. Scanning shall be done at a traverse rate of not more than 2 inches per second.

NOTE: For the XPert Filtered Balance Station, place the sampling nozzle in the center of the remote blower exhaust.


Aerosol penetration shall not exceed 0.01 percent measured by the photometer

Setting the Inflow Face Velocity with the Speed Control Adjustment

1.Remove the front panel by loosening the (2) Phillips screws on top that secure the front panel.

2.The speed control is located on the electrical subassembly located behind the switched control panel and below the front panel. See Figure 6-1.

3.Adjust the speed control with a small Phillips screwdriver by turning the screw counterclockwise to increase blower speed or clockwise to decrease the blower speed. The speed control is very sensitive, so proceed with caution.

4.Measure the inflow velocity per the averaging technique outlined in Chapter 3 and adjust the speed control slowly for the desired speed. Allow the speed to stabilize and remeasure the inflow velocity to confirm.

5.Replace the front panel and tighten the screws.




Chapter 6: Maintaining Your Filtered Enclosure



Calibrate and Operate the Airflow






Guardian Airflow Monitor (LED Monitor)


Refer to Figure 6-2for operation and calibration.



Labconco Airflow Monitor / Airflow Switch Operation





The Guardian Airflow Monitor (LED) consists of a circuit board



and an airflow switch. This switch indicates airflow as safe or low.



It does not provide an actual face velocity, but a small setscrew in



the back of the sensor can adjust the airflow level that it classifies



as “good/safe” or “low/alert.”



The circuit board provides power to the sensor and also contains a



“safe (green)” and “alert (red)” airflow LED indicators, as well as



a “SILENCE ALARM” button to quiet the audio alarm. When



first powered up, the PCB will light both red and green LED



indicators and sound the alarm to indicate it is working. After 5



seconds, the air monitor will indicate either good or bad airflow



based on what the connected airflow switch detects. For low



airflow, the unit will wait for 10 seconds of bad indications before



it sounds both the audio alarm and the red “alert” LED indicator.



If the “SILENCE ALARM” button is pressed, the audio alarm will



be silenced, but the red “alert” LED will remain on. The alarm is



silenced indefinitely unless an airflow change is detected. If safe



airflow is later detected for 10 seconds, the green “safe” LED will



be lit and the “alert” (red) LED will be shut off. At any time the



airflow is safe/good, one can press the SILENCE ALARM test



button and the audio alarm and the red LED will turn on as long as



this button is held down. The PCB has also a two-pinconnector



for use as an external output with isolated relay contacts that close



when the red/alert LED is lit (low airflow). These relay contacts



are not affected by the “SILENCE ALARM” button.



The PCB is mounted behind the front panel using standoffs and an



appropriate label is used to highlight the “SILENCE ALARM”



button with clear areas for the red and green LED’s. No holes to



allow sound to be broadcast louder are necessary.



The PCB can be prepared as a factory special with an additional



connector for the following external inputs, and having the



following possible functions:


Chapter 6: Maintaining Your Filtered Enclosure

External Alarm allows an external signal to sound the alarm, such as a sash open switch, or a “fail” signal from the building airflow system.

Alarm Disable allows an external signal to prevent a “low” airflow alarm from occurring.

Night Setback allows an external signal to prevent a “low” airflow alarm from occurring (not any different from Alarm Disable above other than the terminology.)

Contact Labconco for ordering information on this special PCB.


1.Ensure the flow switch and alarm circuit board are installed and operational.

2.Allow the enclosure to operate for at least two minutes.

3.If factory installed, the monitor will alarm at 60±10 fpm with the inflow velocity set at 90±10 fpm.

4.To change the factory setting, set the inflow velocity required by your Safety Officer to the desired alarm condition using the speed control adjustment procedure outlined in Chapter 6.

5.Once the alarm condition is set, use a small screwdriver to turn the adjustment screw on the airflow switch counterclockwise (facing the screw) until the “low” airflow red LED lights and the audible flow alarm sounds.

6.Adjust the inflow velocity to the nominal operating point required by your Safety Officer.

7.Over time the HEPA filter will load and eventually slow the inflow velocity. Once the alarm condition is met, simply increase the speed control outlined in Chapter 6 or replace the HEPA filter if the speed control is maximized.

8.The table below lists typical alarm conditions based on normal operating conditions. Typical alarm conditions are set at face velocities of 10 to 30 feet per minute below the normal operating conditions due to supply air and exhaust air fluctuations, as well as room air cross drafts. Consult your Safety Officer for proper operating speeds.

Enclosure Operating In-Flow

Alarm Condition Set Point



100 ± 10 fpm


90 ± 10 fpm


80 ± 10 fpm


70 ± 10 fpm


60 ± 10 fpm

50 fpm


Chapter 6: Maintaining Your Filtered Enclosure

Figure 6-2

Guardian Airflow Monitor (LED) with Airflow Switch


Guardian Digital 1000 Airflow


Refer to Figure 6-3for operation and calibration. Refer to the separate Labconco 1000 Alarm Manual for detailed information.


Chapter 6: Maintaining Your Filtered Enclosure


The Guardian Digital Airflow Monitor consists of the airflow sensor, the Alarm Unit, and the 15 VDC power supply. For 115V operation the alarm unit is powered by plugging the power supply into the factory-prepareddigital airflow monitor socket. For 230V operation, the Alarm Unit is powered by plugging the power supply into a building outlet. The alarm has “Enter,” “+,” and“-”buttons to program the monitor. There is also a green LED “SAFE,” yellow LED “CAUTION,” and red LED “LOW” with audible alarm for airflow conditions. The audible alarm can be permanently muted if desired. The Guardian Digital 1000 Airflow Monitor displays a face velocity value, provides an RS232 communications port to a PC or building computer system, can be configured for external input connections such as night setback or external alarm and provides up to three output relays that can be configured. For complete detailed information, please refer to the separate Labconco 1000 Alarm User’s Manual provided with the enclosure.

Digital 1000 Calibration

The filtered enclosure comes factory calibrated with the monitor alarm at 60 ± 10 fpm with the inflow velocity set at 90± 10 fpm. To change the calibration, review the Labconco 1000 Alarm User’s Manual that comes with the enclosure. To successfully calibrate, it will be necessary to change the face velocity by adjusting the airflow exhaust volume with the speed control. The exhaust volume can be adjusted with the speed control or by using an adjustable damper for outside exhaust. NOTE: For accurate calibration, the front panel needs to be in place for each low calibration and high calibration set points to simulate real usage.

Typical calibration conditions are set at face velocity air sample differences of a least 50 feet per minute. However, the airflow monitor is factory set and calibrated with a difference of at least 20 fpm and can be changed in the CAL CONFIG MENU by changing the “lower/higher air sample difference.” If changed, then also change the “sensor difference” in CAL CONFIG MENU from 10% to 3%. To change the red “Low” airflow alarm and yellow “CAUTION” adjust the values in CAL CONFIG MENU. Set “WARNING or CAUTION” air reset to 3 fpm. To complete the CAL CONFIGURATION, be sure to enter “Done.”


Chapter 6: Maintaining Your Filtered Enclosure

To start the calibration, use the Labconco 1000 Manual and enter the “CALIBRATIION” mode on the display. Follow the instructions on the display and alter the low and high exhaust volumes with the speed control. The following suggested inflow face velocity speeds are recommended to successfully calibrate. Typical low air alarms are set 10-30fpm below operational speeds. Typical yellow cautions are set3-10fpm above the red low air alarm. Be sure to enter “Done” after completing the calibration in “SETUP.” Once completed, go to “RUN” and hit “ENTER.”


Nominal Enclosure



Low Air Alarm

Operating In Flow



Set Point


Set Point

Set Point

50 fpm

60 fpm




80 fpm




100 fpm







Factory Settings




60 ± 10 fpm

90 ± 10 fpm

60 ± 10 fpm

90 ± 10 fpm


Chapter 6: Maintaining Your Filtered Enclosure

Figure 6-3

Guardian Digital 1000 Airflow Monitor