Do you hear hissing or whooshing coming from your system? This usually indicates that you have a water leak. However, if not you could still have one. Water leaks in your heating system can be hard to find.
Here is a leak we found in the heating system of a local school in Roscommon recently. Insulation and a taped joint made it quite difficult to locate. We used tracer gas in order to to detect the leak. Helium or hydrogen is used as they are lighter than air. As a result, the gas pressurizes the leaky pipes and it rises out from the leak. We then detect where the water leak is with ease.