DSC Meridian MN140 or MN140C Smoke Detector replacement

DSC Meridian MN140 or MN140C Smoke Detector Alternative Replacement

The DSC 'Meridian' MN140 series smoke detector was a 4 wire smoke detector that was discontinued many years ago.  DSC no longer makes wired smoke detectors so another brand will need to be used to replace a failed unit.  The System Sensor 2012JA is one suitable replacement for MN140 and MN140C detectors.  The 2012J supports the same power as the MN140 and is a 4 wire smoke detector with Form C (both normally open and normally closed) relay output.   When replacing any detector make sure you understand the wiring of the old and new models and test all interconnected units after installation to ensure they are functioning correctly.  If you don't understand the wiring or documents completely please work with a pro installer who does.

MN140 manual:

2012JA manual:

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