When a boiler is installed on an existing central heating system, it is essential that the system is properly cleaned to remove any build-up of ‘sludge’ (which is generally iron oxides). The system should then be refilled and treated with a corrosion inhibitor or protector.
Failure to carry out this procedure (as specified in the Benchmark Central Heating Log Book) during installation may cause the new boiler to be contaminated by debris from the existing system. Because ‘modern’ boilers hold less water and are much smaller than their predecessors, they are more liable to be affected by debris in the system which can put heat exchangers, pumps or divertor valves at high risk. It is important to remember that your boiler guarantee can be deemed void if the debris from the old central heating system damages your new boiler.