Hot water tap running cold after a few mins using Logic Combi 30

[Deleted member 89766]

I have a 5 year old Logic Combi 30 serviced around 4-5 months ago. The rad heating supply is fine but I've noticed recently that if I run the mixer tap in the wash hand basin for a while when shaving, it runs hot for about 30 seconds and then goes cold. I then have to run the tap on full hot for a min until it comes warm / hot again. This is also the same problem with the kitchen sink.

Is there some sort of flow sensor which determines the rate of flow of hot water which may need adjusting?

 

[Rickster123]

You require a gas safe engineer. This forum doesn't give advice on boiler repairs on the open forum.

Thanks