False temperature alarms

I finished installing my security system a couple weeks ago, and set a low temperature alarm for 15 deg C.

Now every 6hrs on the minute, at 9:35 and 3:35 am and pm I get a text message saying that my temperature

has dropped below 15deg, then seconds later, a message saying that the temperature is back to 21deg. Exactly

every 6hrs! on the minute! Tech support could not help other than suggesting I turn off the low temp notification but

thats not an option. I need the freeze protection as I am away for long periods of time. Does anyone know of a solution 

or workaround to this? Anyone with the same problem?