It's not wired in the correct cable, nothing is worth saving in this case as we say. If your not going to rewire it, you'll have to go full wireless which will be new everything.

Ah I see. I can't rewire it easily. It's an apartment so the the bell box is wired all the way to the outside. What cable am I supposed to use to wire this ? 

13 minutes ago, bob2611 said:

Ah I see. I can't rewire it easily. It's an apartment so the the bell box is wired all the way to the outside. What cable am I supposed to use to wire this ? 

Scantronics will give you both wired and wireless solution , enforcer I personally think more complicated 

If you use FSL on the zone selection you will know which wires are faulty to an extent , and you can always put wireless in those locations 

It looks like it's been wired in Cat5 should be "Intruder alarm cable BS4737-3.30:2015" preferably Type 2 or better, which is stranded.

Solid cables are not designed for alarm systems as they can break causing intermittent faults.

thank you for the replies. I will probably not rewire and go wireless.