You will need about fifteen minutes to understand that there will be no hot water or no heating after you switched on the boiler. When this will happen, then, sorry to say, you will be having a real unlucky Monday morning.
As you likely know, the boiler problems will result in a life-threatening instance and the carbon monoxide leaks, and so for you to avoid pointing your property and life in danger, act rapidly and phone Quintessential Plumbing to fix the boiler for you.
Reference: Quintessential Plumbing | 9 Reasons Why Your Boiler is Not Warming Up