Sludge and corrosion are proven to reduce the efficiency and performance of boilers and heating systems, so it's important to protect your central heating system by fitting magnetic filters and dosing with corrosion inhibitor chemicals. Magnetic filters should be fitted into any new build or new installation as well as retrofitted to existing systems - older systems should be power flushed before adding a magnetic filter. Many boiler manufacturers now make this a requirement for their warranty to be valid.
Simple steps like fitting a magnetic filter as well as effective chemical water treatment help to ensure the boiler runs efficiently and could help reduce the energy consumption, saving you money on energy and potential maintenance/repair bills.
Black iron oxide sludge is the biggest threat to a boiler and heating systems performance. Sludge contamination can cause cold spots in your radiators, leaky valves, deteriorating heating performance, noisy boiler operation and potentially cause a breakdown on the system. Fitting a new 'A' rated boiler to an existing system that hasn't been flushed and cleaned thoroughly could contaminate the boiler with sludge, causing the efficiency of the boiler to deteriorate by as much as 12-15% within just a few weeks.
5kg of sludge in a system can reduce the heat output of a radiator by up to 36%. Householders often turn up the thermostat or use secondary heating sources to account for this difference causing a more energy use and a higher energy bill. Installing a magnetic filter to keep the system clear is much more efficient and helps to treat the cause of the problem rather than the symptom.
Heating and Hotwater industry Council (HHIC) propose that on installation of a new boiler, installers should dose the system with cleaning chemicals and inhibitor. For each annual service thereafter, the installer/maintenance engineer would be required to carry out a system water test to confirm the amount of inhibitor in the system stay at the correct levels. Every 5th year, an additional dose of inhibitor must be added to the system - this should be the same product that was initially used during installation to avoid potential incompatibility problems. Every 10th year, the system should be cleaned thoroughly before being re-dosed with inhibitor.