My thermal store is 2 floors above the main living area at my place. In summer, I never know if the water is warm enough from the solar water panels to get a bath or shower on a cloudy day, or if I need to light the wood burner to top up the heat in the tank (I begrudge paying for electric heat, when I have free wood), so I modified an old radio weather station to display the store temperature, and save a 52 step return trip to see if the water is warm. The external temp on the display is now the water temp. The rest of it is standard.