Storage Heaters aren't heating up!

Please can someone advise.  I know nothing about storage heaters apart from the fact that my daughters in her new apartment and hers don’t heat up.  Not sure if we are doing something wrong or the system is broke.   Basically on each side of two of the heaters there are two plugs that are wired to the heater.  One shows it has a fuse and the other doesn’t.  In the cupboard is what looks like an emersion heater.  There are two switches in there.  One that says ‘switch for emersion heater’   The other says Economy 7 supply.  Landlord says switch both of them on at night and turn off in the morning.  Also to set output on the heater to 1 and input to 9.  I’m assuming that’s when it uses the economy 7 Tariff.  We then switched on the power on the right side of the heaters which doesn’t say it has a fuse and expected to have heat and hot water this morning but nothing! All stone cold.  Are we supposed to have the power on the right side of the heater on as well? The one in the hall only has one anyway.  At the moment we are switching the left hand side on today as that then allows us to switch the heater in for heat like a plug in radiator but then we can’t get hot water that way.  Please help!