Flushing and chemical cleaning

On installation of a new system and after installing a new radiator, the entire system should be flushed and chemically cleansed. A chemical inhibitor such as that supplied by Fernox (www.fernox.com) should then be added to the water in the system by your plumber in order to minimise possible corrosion in the radiators and pipework.

If a central heating system has been correctly installed, flushed out and treated with a chemical inhibitor at the time of installation and topped upwhenever the system has been drained down, the radiators should never develop any faults.

Cleaning

The surface of the radiators should be cleaned using warm water and a small amount of washing up liquid. Abrasive and spray cleaners – such as those intended for cleaning sanitaryware, tiles and counter tops – should never be used as they can have a very damaging effect on the finish of radiators and chrome plated valves.

Air in system

Air will often accumulate at the top of radiators when a system is first installed or after the systemhas been drained and refilled. The air should be let out of the radiators using the air vent on each radiator. It is a good idea to check all radiators for accumulated air at least once a year.

For a advice on how to vent your radiators please see our Venting Procedure technical data sheet (pdf)

If air continues to collect in your radiators, this is an indication that something is wrong with your system. Arrange for your central heating system to be checked by a qualified plumber.

'Sticking' Thermostatic Radiator Valves (TRVs)

TRVs sometimes stop working if they are left in the closed position (i.e. position 1 or lower) when the central heating is turned off. To prevent 'sticking', leave all TRVs fully open (i.e. position 5) in the summer when the central heating is not being used.

Creaking noise in the floor or walls

Pipes expand as they heat up and contract as they cool. If the pipe is gripped tightly by timber or a wall, or if it is in contact with another pipe, you will hear a creaking noise when the pipe heats up or cools down. Ask your plumber to rectify the problem by packing felt or pipe lagging around the pipes where they come up through the floorboards. If this doesn’t work, the floorboards will need to be taken up around the source of the noise to establish the cause of the problem.

Humming in the pipes

You may hear an annoying humming noise in pipes if they are undersized for the amount of water they have to carry or if the pump is set at too high a speed. You will need to call in your plumber to find the cause of the problem.

Boiler noise

If scale and corrosion debris collect in the boiler and restrict the flow of water, you may hear excessive boiler noise. This can be very loud. Boiler noise can also occur due to air in the system. You will need to call in your plumber to find the cause of the problem.

Air noise – like the sound of rushing water

Air in the system can cause a noise which sounds like rushing water in central heating pipes and radiators. Refer to 'Air in system' above.