Having a noisy central heating system is annoying and the problem will need to be fixed as soon as possible. The problem is that it is sometimes difficult to determine where the noise is coming from. If you asking yourself, “why is my central heating so noisy” here are some possible causes and solutions:

• Banging and clanging pipes
  if you are experiencing noisy central heating pipes banging or clanging you will need to check to see of all of the pipes are fitted and fixed down properly.. Check to see they are not hanging loose and that they are screwed down tightly. Both of these faults can cause internal banging of the pipes. If the fixing down of the pipes is  correct you may have a simple pressure problem so you can try to solve this by first draining and then refilling the system up again. If there is still banging after you have done this you will need to get an installer to put in wider diameter pipes that are better suited to the new boiler.
• Humming or vibrating noises from a boiler could be a
  sign that the boiler may need re commissioning as the setting up of the boiler maybe incorrect. First check that the thermostat is working correctly and if it is just reduce the speed at which the central heating pump heats the water. Check the system pressure, if the pressure is left set too high damage can be caused to the pipes and boiler especially during winter months when the boiler will be working harder for longer.
• Gurgling and tapping radiators
  can be caused by air build up in the radiators which means that each individual radiator needs the air bled out of the system. Just loosen the air vent connection in the top corner of the radiator by half a turn for a few seconds until water appears so you know that the air has been removed. Tapping noises can be caused by a lime scale build up, to cure this the system needs to be flushed through thoroughly. If this does not work you may need to have your system professionally cleaned by a qualified engineer.
• Bi directional thermostatic radiator valves can be fitted on the water flow into a radiator or on the water flow out, if a clicking noise is being heard coming from a bi directional radiator valve then it is possible that the system is operating above 1.5 bar, if the system pressure is operating at 1.5 bar and the noise continues the problem may be the water flow rate is too high through the thermostatic radiator valve and radiator so the system will need to be balanced correctly, this is done by reducing the flow through each radiator by throttling down the lock shield valve.