Hochiki FIRElink-400CM - Manual (Page 54)

Page 54 of 58 FIRElink-400 Air Sampling System – Installation Manual
© 2010 Hochiki Europe (UK) Ltd 9-5-0-346/ISS4/OCT10
12.5 Detector Sensitivity Varies Over Time
There are many reasons why particle densities may vary, and the ClassiFire system automatically
compensates for this in order to replace the likelihood of nuisance alarms due to normal variations
in background smoke density. Within limits set by the ClassiFire alarm factor, this is a normal part
of the detector‘s working.
12.6 Flow Fault Errors
These occur when the airflow rate into the detector exceeds the pre-programmed parameters. As the
detector ‘learns‘ the flow setup from the initial installation, this usually means that there has been some
change in conditions. A Flow high fault may indicate that a sampling pipe is damaged, and a Flow low
fault may indicate that the pipe has been blocked, for example, by nearby building operations.
If the detector input is sampled from one area and the exhaust is in another area with different
pressure (for example, the detector is in a roof space and sampling from an enclosed room), this
may lead to flow faults. In this case it would be necessary to lead a pipe from the exhaust to the
protected area to ensure nominal flow.
1.1.1 "Low flow" Error Messages.
Check that the pipe giving the error is not blocked
Check that, if the pipe is unused, the flow sensor for this pipe has been disabled (see section
185619544.01.1.1 “Airflow Monitoring (Display / Numeric - Address 001-127)” on page 22).
Check that the low flow fault threshold is not set too high (see section 185619544.01.1.1 “Airflow
Monitoring (Display / Numeric - Address 001-127)” on page 22).
Consider increasing the aspirator (fan) speed (see section 185619544.01.1.1 “Aspirator Speed
(Numeric - Address 001-127)” on page 21).
1.1.1 "High flow" Error Messages
Check that the pipe is pushed home into the inlet and is not broken or cracked
Check that installed pipework is fitted with an endcap. Hochiki’s FIRElink PipeCAD® pipe
modelling software prompts the use of appropriate endcaps. Open bore pipes are not
recommended.
Check that the high flow fault threshold is not set too low (see section 185619544.01.1.1 “Airflow
Monitoring (Display / Numeric - Address 001-127)” on page 22).
Consider reducing the aspirator (fan) speed (see section 185619544.01.1.1 “Aspirator Speed
(Numeric - Address 001-127)” on page 21).
12.7 Cannot Refit the Front Cover
Check that the recessed top edge of the cover is securely located behind the locating guard rails
on the chassis (see section 185619544.01.1.1 “Removal and replacement of the detector front
cover” on page 31).
Check that the key is turned to the unlocked position (anticlockwise)