Casella CEL Airborne particulate monitoring system - Manual (Page 35)

HB3256-03 Page 33
The cleaning interval of the PM10 or PM2.5 head will depend on the particulate exposure level,
an interval of every 3 to 4 weeks is typical.
Cleaning Materials:-
Isopropanol Solvent or mild detergent solution
Lint free cloth or tissues
Cleaning buds
Small brush
All components should be cleaned using the solvent and most appropriate cleaning tool.
Removal of probe/heater.
It should be noted before disassembly that the heater parts should be allowed to cool down.
Remove filter assembly (A) by pulling downwards.
Slacken wing nuts (B).
Holding the heater assembly (C) with one hand twist probe (wire end) towards yourself.
Remove completely wing nuts (B) and outer bracket (D) from the studding.
Loosen allen head screws (E) on the backplate until plate (F) can move freely downwards.
Again while holding the heater assembly (C) carefully remove the probe assembly by pushing
down whilst using a twisting action. Until the probe assembly comes away from the heater.
The probe sealing cap (G) can the be removed from the probe.
Remove part (H) from the probe assembly again using a twisting action.
Any calibration of the probe can be achieved at this stage (see section on calibration of probe).
If at this stage if the heater needs removing for cleaning purposes, this is achieved simply by
pulling the heater assembly downwards, again using a twisting action.
If the heater is removed for cleaning the transit cap can then be screwed onto the support tube
collar.