need a bit of advice my alarm suddenly started going off always triggered by zone 3 so i changed the pir and last night it was triggered by zone 2 the living room any advice is most welcome

When did you last have it serviced or changed the battery?

the battery was changed 6 months ago serviced 6 months as well

The false alarms may be unrelated then

so the system is knackered then i am going to change zone 2 pir and see if that sorts it out

also should i set the alarm with the battery disconnected to see if that sorts the problem out

Sounds to me that u need an engineer. the pulsar panel must be 20 years old by now. too many things could cause the problems you are having, the only one of which a non engineer will resolve being pets.

I suppose you could try fitting a mains filter to the panel, but with that panel you will probably be throwing money away. get yourself a professional in this case imo

also should i set the alarm with the battery disconnected to see if that sorts the problem out

That wouldnt prove anything? A disconnected battery is the same as dodgy battery

if you moved the sensor from circuit 3 to circuit 2 then id suggest you have a duff sensor