hi my pump gave in and i fitted a new one but dah,,,,i forgot to check which way the arrow on the pump was faceing,,,,it comes from the boiler and onto the pump then under the floor to small radiator pipes'i have fitted it with the arrow down is this correct,the pump heats up pretty hot you can only hold the pump for 15sec then too hot.its not a combi its the old one with the tank for hot water beside it,i flushed it out today the radiators and all that work ,if i put it the pump that is to number3 the water realy hot returns to the expasion tank about the speed of pouring a cup of tea