Numatic HZ 190 Owner's Instructions Manual page 10

Low Flow Indicator
This appliance is fitted with a low flow indicator to show that air flow has reduced.
In the event of the indicator light flashing, check the following:-
Dust caps still fitted
Blocked hose
Cloth filter clogged
Hepa cartridge clogged
Variant
Model
Classification
Voltage
Frequency
Power rating
Sound Pressure
Low flow operation
(NB 16L sec corresponds to an airspeed of 20m/sec in a 32mm pipe)
(NB 22L sec corresponds to an airspeed of 20m/sec in a 38mm pipe)
Cause
Bag full
Simplex
190, 200, 250, 350,
450, 570, 750, 900
TYPE H
115 / 120 / 230V
50 - 60Hz
1200W MAX
1000 IEC
68 - 72dB(A) to IEC 60704-2-1
+/- 0.2dB(A)
16L/sec (0.96m3/min)
Remove and replace, clean dirty filter by
Replace, seek advice from an instructed
person or manufacturer.
HZ
10
Solution
Remove the caps.
Unblock the hose.
Remove and replace
vacuuming.
Duplex
HZD
450, 570, 750, 900
TYPE H
115 / 120 / 230V
50 - 60Hz
2400W MAX
2000 IEC
72 - 78dB(A) to IEC 60704-2-1
+/- 0.2dB(A)
22L/sec (1.32m3/min)