Ferroli optimax HE 31C, c/h but no hot water?

Currently in a student house, just got back after easter break and whoever left the hosue last turned boiler off at the wall. Came back today and switched everything back on, and pressure is fine, but can't get any hot water.

When turn any hot tap on, symbol comes up on LCD saying its heating the water for it, but only cold water comes out, and when left alone (not on eco mode) it heats the water for the tap but then pumps it round the central heating. I have stood in front of the boiler watching the LCD and has never come up showing it was heating water for the radiators, so I can only assume it's pumping the water round that's meant for the tap instead.

Have rang the landlord up, who built the house in the first place, and he hasn't got a clue. Anyone know what's going on as I really don't want to ring the support line on my mobile as we dont have a phone in the house.