MAN2285-9
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13
Trouble shooting
13.1
Nuisance alarms occur too often
➢
Check that the ClassiFire alarm factor setting is appropriate for the normal working environment of the
protected area. (see Section 4.6)
➢
Check that the detector is not in Demonstration mode. This can be ascertained by viewing the event
log (see Section 3) and checking that the entry Demo mode has a higher log entry number than the
most recent FastLearn start and FastLearn end entries. Remember that the log entries are in reverse
order, with the most recent entries appearing first.
➢
If the log shows that Demonstration mode was invoked during the last FastLearn period, start a new
FastLearn and allow it to complete its 24-hour cycle. (see Section 4.8)
➢
From the event log (see Sections 9), check that 24 hours have elapsed since the last FastLearn end
entry.
➢
Check that day-night switchover times are appropriately set to reflect active and non-active periods
(see Section 4.12 and 4.13).
13.2
Elevated smoke levels do not generate alarms
➢
Check that detector is not Isolated or in FastLearn (if Isolated, the Fault light will be lit)
➢
Check that the detector sampling points are in the smoke stream
➢
Check that the correct ClassiFire alarm setting has been set (see Section 4.6)
➢
Check that the detector has either had a 24 hour learning period or that it has been placed in
demonstration mode.
13.3
Low mean output
Check that the filter does not require changing (see Section 4.34) and that the air plenum chamber is clean. The
chamber may become clogged when, for example, heavy building activity has occurred near the sampling
pipes. If so, the chamber may require factory service. The detector is not designed to handle large quantities of
coarse debris and dust.
13.4
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 alar
m factor, this is a normal part of the detector‘s working.
13.5
Flow fault errors
These occur when the airflow rate into the detector is outside the pre-programmed limits. 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, e.g. by nearby building operations.
If the detector input is sampled from one area and the exhaust is in another area with different pressure (e.g.
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 normal flow. This will
require the detector to be installed using the piped exhaust docking station (see section 7.1).
13.5.1
"Low flow" error messages.
Check that the pipe giving the error is not blocked
Check that the low flow fault threshold is not set too high (see Section 4.30)
