Problems with rc10/433-gb ?

I had the rc10/433-gb and the rdh10rf installed about 6months ago with my new boiler.since using the heating over the last few cold months the light goes red on the receiver and stays on....even pressing the buttons did not make it work so today I had new set of the above installed and after about 30 mins the same happened all over again.has anybody got any ideas as to why this is happening because I'm about to beat it with a hammer