Chapter 5: Troubleshooting
LaserSense HSSD-2 Aspirating Smoke Detector Installers Handbook 65
Problem Solution or corrective action
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 operation.
Flow fault errors These occur when the airflow rate into the detector exceeds the
preprogrammed 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, 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 nominal flow.
“Low Flow” error
message
Check that the pipe giving the error is not blocked.
If the pipe is unused, check that the flow sensor for this pipe has been
disabled. (Refer to “Airflow monitoring” on page 51 in Chapter 3 for
details.)
Check that the low flow fault threshold is not set too high. (Refer to “
irflow
monitoring” on page 51 for details.)
Consider increasing the aspirator (fan) speed. (Refer to “Aspirator speed”
on page 50 for details.)
“High Flow” error
message
Check that the pipe is pushed home into the inlet and is not broken or
cracked.
Check that installed pipework is fitted with endcaps. PipeCAD pipe
modeling software prompts for the use of appropriate endcaps. Open bore
pipes are not recommended.
Check that the high flow fault threshold is not set too low. (Refer to “
irflow
monitoring” on page 51 for details.)
Consider reducing the aspirator (fan) speed. (Refer to “Aspirator speed” on
page 50 for details.)
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.
Check that the key is turned to the unlocked position (counter-clockwise).
No display Check that the display ribbon cable is securely connected to the
detector/command module main board and to the display board as
appropriate.
Check that the display ribbon cable has not been damaged.
To Next Page
Loading...
