Disabling an old house alarm without the codes?!

I assume there’s another battery in the siren box thing 20 feet up that I can’t reach?

I think that's often the case, yes. We had an alarm engineer out for a very similar issue. He was able to reset the system and provide a new code. I presume there are different alarm brands and they may not all be the same but that's where I'd start.

Thanks

Hmm, the alarm is completely knackered so I’m not sure whether it’s worth getting reset (PIR sensors taped up, broken reed switches etc)

Anyone know how long an external alarm box battery lasts if I just let it ring…?!

If you can get up to it and get the cover off then you can easily fix it. If you don't want to mess about getting the cover off then expanding foam inside should do the trick.

Yeah, I had a similar situation when we moved. It went on for quite a while from memory - maybe 3/4 hr to an hour and then finally stopped. It was ****ing loud.

Anyone know how long an external alarm box battery lasts if I just let it ring…?!

Long enough for your new neighbours to pop round and murder you 😉

Hmm, I might be able to reach the box from a window but it’s stupidly loud and my tinnitus has gone crazy already.

Turn the lights off and pretend I’m but home for an hour?!

Well I just got the hammer and the earplugs and it’s stopped (16 mins).

Thanks guys. The flipping thing is going to be removed very unprofessionally..

Have you tried some random codes (ie, 1234, 1111 etc). Or could you look online for default codes for the particular brand? Or just call a local alarm installer – there would be a call-out fee, but I'm sure they deal with that sort of stuff all the time. Also - is there a fitter's name on the unit (ie, the name of the local company that fitted it). They may be able to help.

Have you tried "1234"?

Can you contact the previous owners via estate agents / solicitors and ask?

Long enough for your new neighbours to pop round and murder you

I was literally just about to post "long enough to make a lasting first impression on your new neighbours."

Alarms have failsafes and tamper protection by design. It's a pain, we inherited a comprehensive system that we cannot use because the cats would set off all the PIRs. The only time it sounds is when there's a powercut.

He's done it. Can you not hear that the alarm has gone off now?!

because the cats would set off all the PIRs

You can get pet friendly PIR's or just tape up the bottom half of the PIR lense with insulating tape. I've done both without being murdered by the neighbours (yet).

British Standard was 20 mins max.

There's often a jumper to set that clears the codes back to default, but that assumes a manual available online somewhere

The battery is possibly inside the control box, they need testing every year or two

I haven't had anything to do with them for a long time though

The battery in the control panel is designed to keep it running during a power cut.

The outside siren box will have a battery back-up also but as said above it should silence itself after a period of time and then reset.

Removing the siren box cover will trigger the tamper circuit and sound the alarm again.

But looks like you're sorted now anyway!

Move house?

(we inherited one once as well. A half hour, a ladder and screwdrivers and we were sorted with all the batteries and bells removed, just a few odd cables to pull through. My hearing took a few hours to recover though.)

When we moved in we inherited an old alarm.  We had the fuse box replaced and as part of that the electrician must have disconnected it.  It went off about 8pm just after we had got my two boys to sleep (around 1 and 3).

Couldnt turn it off, had a house of crying children and angry wife so I ended up leaning out of an upstairs window hitting the thing with a hammer till it fell off then wrapped it in a sheet and stuffed it in the garage.... there are probably better ways to do it:)

You can get pet friendly PIR’s

This I knew.

or just tape up the bottom half of the PIR lense with insulating tape.

This I did not. Interesting, thank you.

I had similar problems during extension. If it's old enough the batteries will give in within half an hour or so. Assuming it's similar to ours, if you can find the technician's manual for the control box there's a method to reset the system to default (ie 1234 or whatever the default PIN is). Otherwise just pull as much power and batteries as you can in daylight and wait for any other batteries to lose power.

Ancient ex alarm service guy here, helpful if looking at an ancient intruder alarm . Obviously you’ve sorted it OP.

Yes you can mask PIRs for pets but even 20 years ago when I got the hump with the industry, pet friendly pirs were a very cheap option on proper wired systems.

Yes the sounder ‘should’ stop after 20 mins. If you post a pic of the system I could probably say if it’s worth saving or throwing in the bin. Some of the old systems were pretty bullet proof.

All that said, despite the fact I could fit one for free, I’ve never wanted an alarm on my house.

There is a way of shutting the sounder up from inside, but it’s a bit risky and a big no from a health and safety point of view.

12 months after I moved into my last house, I was speaking to my neighbours before I went away on holiday and debating whether to leave the alarm on as it would disturb them if it went off. They replied "Dont worry we know the code and have a key if needs, oh maybe we should have mentioned that earlier!"

"oh no, thats cool then" I said

All that said, despite the fact I could fit one for free, I’ve never wanted an alarm on my house.

TBH all you really want is the alarm box 🙂

There is a way of shutting the sounder up from inside, but it’s a bit risky and a big no from a health and safety point of view.

Surely I'm not alone in wanting to know this?!
I'm guessing it's usually a low voltage circuit and the method involves 230v?

Haha - sold my mates house with no knowledge of the alarm codes, on behalf of the deceased I apologise for all those above who have inherited troublesome alarms in their new homes.

I’m guessing it’s usually a low voltage circuit and the method involves 230v?

Something like that. I’ve obviously never done it rather than hang out a window on the end of a ratchet strap, or to avoid other ridiculous working at height issues.

TBH all you really want is the alarm box

This!
We've neighbours who we hold the key for when they are away. The alarm sounds most times they go on holiday...I just end up turning it off now, and not resetting.

12 months after I moved into my last house, I was speaking to my neighbours before I went away on holiday and debating whether to leave the alarm on as it would disturb them if it went off. They replied “Dont worry we know the code and have a key if needs, oh maybe we should have mentioned that earlier!”

You didn't change the locks? It was the first thing I did when we moved four years ago, I'd measured up the locks and bought replacements before the sale had completed.

Granted though, this place used to be a foster home of sorts for adults with learning disabilities so it was an atypical situation, there could've been dozens of keys out there and I didn't a bewildered former resident climbing into "their" bed with me in the middle of the night.

We purchased a house with an existing house alarm system but no master code available (previous owners also inherited it and did not understand what we were asking for) - so we couldn’t make any changes or re-configuration.

Downloading an online manual revealed that you could take the front panel off and put a jumper between two pins on the motherboard to reset it to the factory default master code.

That’s fairly common. Often it’s a case of all power off, connect link, then power back up. Expect some noise though.

The earlier microprocessor panels would have no NVM or would have a long dead PCB battery, so any loss of power would default everything, entry/exit zones, timers etc.

I used to like the old logic panels with a key switch. Utterly bulletproof. Some had a keypad you physically wired the code in.

Whatever it is, a nice healthy back up battery will  help reliability. 7ah if it’ll fit.

We had this. The siren battery will go off for 10-20 mins maybe then stop. Just got to wait it out.