Evening all. Last month i had a new Worcester Bosch Greenstar Compact 32CDI combi installed. I have come to notice that when the CH is on there are drastic fluctuations in the temperature of the hot water when the tap is on. The water temperature is currently set to 46 degrees on the boiler. I tested the fluctuations with the thermocouple on my fluke multimeter. When turning the tap on the cold water naturally comes out the pipe, then the temp goes up to between around 36 and 46 degrees, then back down to around 17 degrees, then up to around 36 degrees, then back down to around 25 degrees, then back up to around 36 degrees before it very slowly climbs into the 40s over the next couple of minutes. The temperature is fine when the CH is off, After the cold has come of the tap I am getting a very constant temperature in the mid 40s. Surley it cant be normal for the temperature to fluctuate so much? Please could somebody help shed some light on the issue? Should I get on the phone to worcester bosch? Many thanks.