i have had a salus rt500rf thermostat fitted 3 days ago set up the programme no probs. the low battery indactor came on changed batterys pressed reset re programmed it but low battery indactor still comes on when it is in programme mode ie when the heating is set to come on low battery indactor goes of when heating should go off . i have thermostat radiator valves so heating not on at the moment as the boiler is in summer mode why does the low battery keep flashing.