Tripping Smoke detector

[alanthomaswatson]

Hello

Bit of a weird one.

We have two hard wired smoke detectors, one at the top of the stairs and one at the bottom. These are on the upstairs lighting circuit.

Occasionally, switching on a light upstairs sets off the smoke detector, which stops once the light is switched off again. It's happened with two different switches.

The detector downstairs can be a bit tricky and if taken down to change the backup battery sometimes goes off when reconnected, although not when first connected, only when the detector is turned onto the fixing plate.

Could it be that one of the connections to the downstairs unit is loose?

Any other ideas.

Thanks

Alan

 

[Taylortwocities]

Sounds like pick up from the wiring.
Are the alarms linked by 3-core and earth cable. Is the cpc in the cable properly earthed?

Many alarms do chirp after being reconnected to the mains (ie put back in their base).
What is make & model of the alarms?