I have been having problems with my fridge freezer for several years (from new in fact). Every few months the fridge would get warm and by the time we noticed, food was spoiled. It was also hit and miss when adjusting the controls. This dual thermometer was very easy to fit as it is all pre-wired and allowed me to setup the controls easily. We do not use the alarm as it would be going off every time the door was opened. The original problem with the freezer was fixed after some internet research. Stripped about 30 cms of copper wire from some old mains cable. Wrapped one end round the de-frost heater and poked the other end down the drain hole. This prevents the drain from becoming blocked with ice. This tip saved me several hundred pounds for a new fridge/freezer. The thermometer continues to give re-assurance that all is now well.