Worcester Highflow 400- water too hot, how can I turn it down?

Ever since installation about 5 years ago, the hot water delivered to the taps has been scalding. The hot water dial is set at minimum. The water flow rate is very good to the boiler (i.e., no problem with water flow rate in our area). Is there any other way to reduce the water temperature? Or is the boiler supposed to deliver such hot water? Thanks.