Accenta G3 Battery change?

I have accenta alarm, cannot find model number, it was fitted 14 years ago. Problem now is beeping noise from box when passing sensors. I have opened box but cannot see battery, there is a small black cylinder shape with hole in middle I think the battery maybe underneath but cannot remove black cylinder without force and might break it. Ref. No. on black cylinder shape is
HCM1212A. 119KIJ. Can you please help

Brian Middleton
October 2017

How do I change the battery? Can you talk me through step by step please.

Thanks
Lou

Lou Meredith
August 2013

open cover and alarm sounds,
enter code alarm stops,
change battery,(2 terminals)
replace cover enter code then test alarm.

Bill
July 2008

Thanks for confirming it's the battery.

But how do I change it?
Do I enter the engineers code and then remove the cover?

Fish Lord
May 2008

Hi, Yes if you remove the mains and the bell rings the battery is flat.
You can change the battery in afew seconds so it's no problem.
Rob

Rob
May 2008