The answer to 'why is my boiler' is that there could be several common issues causing problems with your boiler. Some of the most frequent causes include a lack of water, issues with the pilot light or ignition, problems with the thermostat or controls, or a malfunctioning pump or other component. Symptoms may include the boiler not turning on, strange noises, leaks, or inconsistent heating.
In many cases, the solution could be as simple as resetting the system, adjusting the thermostat, or relighting the pilot light. However, more complex problems like a broken part or a system that needs to be serviced are best handled by a professional HVAC technician. Attempting DIY repairs on a boiler system can be dangerous and may even void the warranty, so it's generally recommended to call in an expert unless the issue is very minor.