Pressure is an exertion force that is found in central heating systems. Pressure helps circulate the hot water around the central heating system, without adequate pressure then the central heating system will not work correctly. The normal operating water pressure for the central heating system is between 1.0 and 2.0 bar and most modern boilers will feature a pressure gauge so that a user can see what the current operating pressure is. When pressure drops below the standard operation level the central heating system may need to be re-pressurised.