No hotwater

I have just moved into a new house with a pulsacoil a class. Initially I turned everything on and nothing was working so I tried resetting it in case there was an overheat sensor tripping. Still didn't work then I realized the feed tank was empty. Topped that up, many times! And now it's full. But still no hot water! The boiler itself feels very warm but the outlet pipes from it are v cold!
Anyone here can advise? Or recommended me Someone who can come to my rescue soonest as no hot water in this weather is miserable!
Thanks

I am in Sheffield btw