No Hot water pressure in kitchen with pump system, rest of apartment is fine.

Hi. Have an interesting problem with hot water pressure in our apartment. The hot water in the kitchen is nearly non-existent. The rest of the apartment is fine, shower and bathroom sinks work as expected. We live in one if these new-fangled apartments here in Dublin, the hot water heater and pump can't be more than 3 years old.

The system has a pump to circulate the hot water. When I turn on the kitchen hot water I can hear the pump turning on, but there is no pressure. There are no leaks coming through in our apartment and the unit below hasn't complained of any either.

Does anyone out there have any experience with this sort of problem? I am about to call a plumber, but don't really know too much about these systems so would like to get at least an idea of what the problem may be first.

Any help is greatly appreciated.