Three Towns Forum

Members' Lounge => Help Centre => Topic started by: Fester on December 10, 2014, 12:32:38 pm

Title: Smoke Alarms
Post by: Fester on December 10, 2014, 12:32:38 pm
When my old battery powered smoke alarms used to get 'low' in power, they used to bleep at me.... and I would know to replace the batteries.  Fair enough.

But when I had the house re-wired, they fitted mains powered smoke alarms..... which I assumed needed no battery.
I thought I might save a few bob.

However, three years on, one kept bleeping all last night, and kept us awake... so I switched the mains off and removed the battery.   I was surprised to see a battery in there!
What is the point of a battery in these devices, if the mains is a constant supply of power?
Title: Re: Smoke Alarms
Post by: Jack on December 10, 2014, 12:56:54 pm
Isn't the battery there as a back up in case of a power cut?
Title: Re: Smoke Alarms
Post by: Merddin Emrys on December 10, 2014, 02:28:48 pm
Back up for a power cut, that was my first thought too!
Title: Re: Smoke Alarms
Post by: Nemesis on December 10, 2014, 03:49:27 pm
When my old battery powered smoke alarms used to get 'low' in power, they used to bleep at me.... and I would know to replace the batteries.  Fair enough.

But when I had the house re-wired, they fitted mains powered smoke alarms..... which I assumed needed no battery.
I thought I might save a few bob.

However, three years on, one kept bleeping all last night, and kept us awake... so I switched the mains off and removed the battery.   I was surprised to see a battery in there!
What is the point of a battery in these devices, if the mains is a constant supply of power?

Ours is mains powered, but being commercial premises is subject to regular checks. Do you have an instruction manual for the system? If not it could be an idea to contact the firm or the company who made said alarm.
Title: Re: Smoke Alarms
Post by: Jack on December 10, 2014, 03:57:47 pm
Nem, yours will have a back up battery too but is inside the control panel rather than each individual detector.
Title: Re: Smoke Alarms
Post by: Fester on December 10, 2014, 06:25:27 pm
Isn't the battery there as a back up in case of a power cut?

Probably.... and I've put new batteries in now, cos if you don't .... you don't sleep!