crazy temp alarm kept going off once i installed the optical cable , any idea?

[chercm]

every time the optical triggers the pump to top up . the temperature alarm will go off showing 38 degrees .

what is going on ?

[Gunther]

Sounds like you have a loose contact in your temp sensor cable or the plug is loose & vibration of pump will cause the errror
Another reason may if you have the cables of pump and temp sensor side-by-side -> electromagnetic interference.

[chercm]

i have secured the cable .