Most people experience blockage or problems in the expansion tanks of their boilers but the good thing is that the first thing they do, is that they call Boiler Breakdown Harrow. But to understand these expansion tanks you must know that there are mainly two these tanks when it comes to the boiler that works with hot water. The old style of these includes a large tank which is horizontal and is made out of steel. The new style includes a tank with a relatively smaller and more efficient diaphragm. In the older systems of these boilers, the expansion tank which is made out of steal, may be placed in your buildings attic or is located between the basements. While the diaphragm of the new expansion tank systems, is supposedly attached to the pipes of the boiler. You must properly charge the expansion tank with the help of air so that the entrance of water can be avoided. This saves your boiler exceeding the boiling pressure of your desire. Once that fin-tube or radiation convector gets heated up with hot water in the boiler, the water then returns to its previous destination which is the boiler. It returns back so it can be heated again and the loop of water circulation can further continue.This simple boiler in your house can use propane or natural gas in case it is a boiler that works by firing up gas and if it works by firing oil that oil is the best fuel for it. However, the boilers which run on oil need more attention and care that the ones running on gas. These differences can easily be pointed out but the equipment to fix these is a lot complicated that is why you need assistance from Boiler Repair Harrow.