External PIR & steam

Does anyone know if an external PIR (5750WPL) would be effected (ie. have false triggers) by steam. The best location I have for the PIR is on the same wall as the output from my condensing boiler. The vent is about a meter of so from where the PIR will be mounted. I'm concerned that if the wind is in the wrong direction and the steam goes across the PIR's field it will trigger.

JB

PS. The 'steam' coming from the boiler is around 56 deg C so shouldn't damage the PIR.

 

I'm predicting problems for you Ben. The chances are that the PIR will 'see' the air heated by the steam to ~ 50C floating past, treat it as the type of change in thermal profile it was designed to detect and bring on the load.

My favorate PIR story of this kind was where every night when a guy in a house equiped with C-bus went to the loo the out side lights (controlled by a PIR came on then timed out. Initally it was thought that the inductive nature of the fluro lamp and or exhaust fan in the bathroom was causeing interference as they were switched on by the C-bus switch in the Bathroom via the C-bus relay output, and that this interference was causing the out side PIR to falsly trigger on.

When I visited the site I found that the Bathroom exhaust fan was of the ducted variety and that the duct came out right infront of the PIR so that when the guy switched the light and fan on the rush of (comparativly) warm air would squirt out in front of the PIR and cause it to trigger on.

 

That was the answer I was expecting really, but not having any practical experience of PIR's I wasn't sure what real world experience would show.

I'll see if there is anywhere else I can mount it.

JB