hello Advice or insight sort. Our Worcester Bosch 350 combi boiler has developed an intermittent problem. After the hot water has been running for a time, eg. after a shower, the overheat thermostat pops up and ths system shuts down. Doesn't happen when the heating has been running for a long time, only with the hot water. Doesn't happen everytime the hot water is used. Any ideas what's wrong?
bella2002tii