OPERATOR'S MANUAL BIOPROtect II Vent to ... - Baker Company

V. - TROUBLE SHOOTINGHere are some suggestions based on our experience with the use and misuse of biological safetycabinets.CAUTION:Whenever the potentially contaminated areas of your cabinet must be entered, make sure that the unit is firstdecontaminated by use of an appropriate method by qualified personnel.Also see section 2 “Decontamination”When a smoke test indicates that there is air flowing from the interior of your cabinet into thesurrounding room:1. Make certain that the front doors are closed and the front intake grilles are not blocked. This willcreate 8”x 42” horizontal openings in the front of the cabinet.2. If your cabinet is connected to an in-house exhaust, make sure that there is adequate exhaust suctionand no back pressure. Also, be sure the dampers are open. Re-balance the exhaust system to handlean adequate quantity of air and static pressure (suction). Consult with building maintenance people.3. The exhaust filter may be loaded with dirt if the unit has been in service for some time.Decontaminate, and replace the HEPA filter.4. There may be high cross-drafts in the room which are causing the outflow of smoke. Check theairflow balance, following the procedure recommended in an earlier section of this chapter.Eliminate the source of the cross-draft.If there is no airflow within the work area:1. Make sure that the blower switch is turned on. The indicator on the push button should beilluminated.2. If the lights are working, then turn the blower switch off and let the cabinet rest for ten minutes.When the time has passed, turn the blower switch on again. If the blowers start, you know there hasbeen overheating of the blower motor(s).Also check the wiring connections inside of the lightcanopy which connects the canopy to the cabinet. Be sure the connections are pushed together.3. If these solutions do not correct the problem, or if the blowers failed to start after the rest period,then either the speed control, blower motor(s) or capacitor is defective. A qualified electrician canfind out if the speed control is defective by bypassing it, using the wiring diagram in the Appendixof this manual as a guide. If there is a noise problem, it may be caused by motor bearings.When there is uneven fan operation, or noise from the motor/blower assembly:1. It may be necessary to decontaminate the cabinet.2. Look for loose objects in the fan cage.3. Check to see if the fan wheel is contacting the blower housing.4. Open the light canopy and check the multi-pin connectors at each end to be sure they are securelyengaged.5. Another possible source of the problem is the speed control.Page 24 of 54