Sludge is a build-up of metallic oxides in your heating system; most commonly Iron Oxide (rust), but copper and aluminium oxides can also form.

There are many ways to check for sludge in a heating system. 

The easiest way you can test before contacting us is:

1. Turn up your thermostat until the boiler kicks in, and wait for a few minutes for the system to warm up
2. Using the back of your hand, check the top and bottom of each radiator, each half should heat evenly
3. If the top is cold, this indicates an airlock in the system and doesn't normally require professional intervention
4. If the bottom is cold, this would be a sign of sludge in the radiator
5. However, if the entire radiator is cold, this does not always indicate sludge

If this method doesn't work for you we have many ways to check the system internally. 

We normally start by checking circulation pumps, and plate heat exchangers (if your boiler is fitted with one).

• Circulation pumps use a magnetic coil to spin the motor. This attracts the magnetite and blocks up the impellor
• Plate heat exchangers use a series of very narrow channels to instantly heat hot water using the heating system. The heating passages can become blocked with sludge.

We then conduct visual checks on the water in the system. 

• A small amount is drained from the system and inspected for debris. 
• Sometimes, the water is very evidently contaminated and will come out of the system as a brown or black colour and have large floating particulates.

If we have any doubts with the result we then use a specialised chemical testing kit to test the pH of the water.

• Good quality water has a pH of around 7, any reading outside of this will indicate sludge contamination as well as the severity of the contamination.

The most effective way to remove sludge from a heating system is a powerflush. 

We use an advanced Norstrom Proflush machine paired with an Adey Magnaclense filter system. 

The Proflush gives us enough pressure to effectively clear your system, while the Magaclense collects all the debris.

We also add an acidic compound to the Proflush to further clean the system. We have used Kamco FX2 for many years and it has proven it's effectiveness as a cleaner, and we wouldn't recommend anything else.

A powerflush can remove up to 90% of sludge contamination in a boiler and heating system.

Alternatively, we do offer a less intensive solution, where we just use an acidic compound and let it run through the system for a few weeks, with your circulation pump taking the place of our Proflush machine.

This is significantly less effective then a full powerflush, but can still clear a decent amount of sludge.

While sludge is unavoidable, there are many simple and effective solutions to slow the formation of large deposits, keeping your system running - especially during the cold winter months.

Older Installations (Before 2019)

If you boiler was installed prior to the regulation changes the best practice is to flush the system, install a magnetic filter and keep the inhibitor topped up every few years.

Newer Installations (After 2019)

Regulations for new installations mandate that a heating system must be:

• Flushed/Cleaned - Either with a power or chemical flush
• Fitted with a magnetic filter
• Treated with chemical inhibitor 

If you had a boiler installed after 31/05/2019, your installer has to adhere to the points above to legally comply with regulations.

This is covered under British Standard 7593:2019 to comply with Building Regulations Part L.