Anyone, Please HELP

We bought our house 2 years ago
The old owner did not transfer his ADT contract and installation when moving out
I contacted ADT back in March 2013 saying that they will simply disconnect it and to not worry

RIGHT... Well, tonight and after nearly 2 years the indoor little box started beeping and it is a very frustrating noise
I called ADT but they are not helping. They are not taking responsibility and they want us to pay £133 for their engineer for half an hour work who can only come by tomorrow... Absolutely ridiculous

Anyway, we need help as it is very annoying and as it would be nice to be able to get some sleep before work tomorrow.

The issue is as follow:
- ADT service is disconnected
- The little box in the hall show on the screen a phone with a cross on it, an alarm and a battery with a cross on it
- The little box is quite small and under the screen there some digets on buttons
- No light flashing
- It is a constant beep
ADT say it is due to low battery but how do I stop it

Please help

Thx
Karine

Thanks you to Ron the issue is solve and well happy :)

How was it solved if I may ask to satisfy my curiosity?

Karine, because your question was originally piggy-backed onto another thread, I moved it to its own thread before your second post.

I am guessing that Ron was poster in the other thread. Do you mind sharing what advice he gave that you followed?

Hi Talaniman and Cat
Ron is a local engineer who was really helpful... our saviour :) + we did everything over the phone which saved us on cost.
He advised that even if they were no service, i.e. the contract had been stopped years ago it did not mean that all was disconnected.
He informed us that the best way to do this was to remove the battery from the system and the fuse from the main alarm compartment.
Prior to do this please be aware that the outside alarm will go on for 20 minutes so better inform the neighbors.
We sent him a picture of the mother board and he advise to remove the red wire linking to the battery. Once done to remove the fuse which is in a tiny little place.
Normally the outside alarm should have gone off but did not in our case. Ron said that it was good in this occasion but should not have been the case.
Anyway, the bip stopped. The full system is disconnected and we are reallly happy :)

Thank you for responding and congratulations on fixing the problem.