MKS

This looks like a good option, thank you. some is some isn't. I'll change other bits as they fail

Hi, I have a scantronic 9800 alarm system. It has served me well over the last 30 odd years. I installed it myself and have updated it several times over the years. A few weeks ago I noticed that the exit tone had gone from intermittent to continuous. Didn't think to much of it as everything is still working. Then I noticed I was getting the exit sound on B and C part set. When I had some time I decided to check the programming as I also have some new detectors to add. Well the engineering code didn't work. I tried all options including the factory default, no luck. So I opened the alarm and cleared the code using the user code which still works, it isn't the default. I took the NVM chip out and followed the reset procedure for lost engineering code and recommissioned the system and set a "new" engineering code. Everything working fine. All sensors working as expected on walk test and alarm working correctly. All good.....well only for a few days, then the exit tone has reappeared on part set. I suspect the NVM chip is loosing data and may be failing. Anyone think I am on the right track? Is there anything I can do, or is it time to replace the system. If so what would everyone suggest for a wired system? Many thanks for any pointers you can offer.