How do I turn on my central heating

 moved in 3 days ago so it must work  and I can’t call landlord or letting agents I have a heatwave sadia  electromax and we have hot water and electric but no heating am I doing something wrong I have the tap and the radiator illuminated on the boiler but the hot water turned off via the programmer on the wall but if I turn it on  the boiler makes some noise then it sounds like it’s turning itself on And then sounds like a kettle but still no heating so cold brrrrr 

Have a look for a dial on the boiler, what does it read when heating off? 

Is there a pressure gauge on it....if it's a combi?  Should read at leas 1bar