I am thinking about installing a home alarm system. As my house has a warm air heating system, I am wondering whether I am likely to experience false alarms triggered by it cycling. Obviously, alarm PIR's cope with conventional radiators but these will have a much more gradual change in temperature as they warm up. A warm air system will produce a quite quick thermal "bloom" I would imagine. I do not think it would be possible to site PIR's so they did not see this, but I might be wrong. Does anyone have any experience in this area?
PIR's and warm air systems
- Thread starter ianbar
- Start date
Sponsored Links
PIRs in a remote equipment room were occasionally ( but too often ) triggered when fans in equipment started up and blew warm air out of the racks. The PIRs had to be replaced by break beam detectors.
Why not just use a decent quality dual technology (DT) detector?
DT's use PIR and microwave technologies which both need to be tripped before generating an alarm.
Essentially the PIR is looking for heat movement across the field of view whilst the mircowave is looking for physical movement towards and away from the device, it's more involved than that but you get the idea.
I've actually put a DT right next to the blower in my parents house without ever an issue. And before someone starts it was the only place it could go
DT's use PIR and microwave technologies which both need to be tripped before generating an alarm.
Essentially the PIR is looking for heat movement across the field of view whilst the mircowave is looking for physical movement towards and away from the device, it's more involved than that but you get the idea.
I've actually put a DT right next to the blower in my parents house without ever an issue. And before someone starts it was the only place it could go
D
doingitmeself
Get decent quality dual tech detectors and you won't have any problems. I would recommend the Risco iWise dual techs - I have a couple mounted directly above radiators and have never had a single false activation.
Sponsored Links
C
chaindaisy
Just come across this one, so apologies if I'm late.
It depends also on the fan motors. We had a problem at one time with fridge/ freezer motors causing an alarm condition. Not knowing much about quads wouldn't this phenomenum give rise to similar probabilities ?
It depends also on the fan motors. We had a problem at one time with fridge/ freezer motors causing an alarm condition. Not knowing much about quads wouldn't this phenomenum give rise to similar probabilities ?
Quad are dual element PIR's rather than Microwave and PIR so are essentially looking at the same area for infra red heat movement.
C
chaindaisy
I see, so could an induction motor acivate a quad pir ?
Because of heat, interference, position in room......?
C
chaindaisy
I was thinking of mains transients or spikes mainly. Would appreciate your comments.
DIYnot Local
Staff member
If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Are you a trade or supplier? You can create your listing free at DIYnot Local
Sponsored Links
