How do I turn my water temperature down?

[katieg]

Hi, Id like some advice on how to turn my water temperature down as it is currently scolding hot. Id like to do this without turning the heating down. We have a Potterton Gold H boiler. There is no thermostat in the house and no buttons or knobs on the boiler. Do I need to get a plumber to turn it down from the inside?
thanks,
Katie

 

[jtsplumbing]

Should be two control knobs on front of boiler one for heating one, (right hand ) for hot water pull down the flap on the front of the boiler