Why is inhibitor important to use?
An inhibitor chemical solution is put into the central heating system to prevent build up of sludge and limescale. This keeps the system clean and work more efficiently and helps to prolong the life of the boiler, pipework and radiators too. It’s important inhibitor is topped up every time the system has been drained and refilled with water.
Why is adding inhibitor important?
- Protects against corrosion and scale. even in central heating systems that have dissimilar metals like aluminium, copper, and brass etc. to prevent boiler breakdown due to blockage and damage to components
- It helps the system run efficiently. like radiators get hotter quicker
- Is cost effective to help prevent breakddowns. A typical one litre bottle can treat a full house system up to 15 radiators.
- Prevents cold spots in radiators. so the room warms up quicker
- Boiler maintenance costs are reduced. Due to replacing parts are reduced and an efficient heating system saves on energy bills.
What is central heating inhibitor made of?
An inhibitor is made up of chemicals such as benzotriazole, sodium molybdate and sodium nitrate. It is added to the central heating system to prevent rust and corrosion of the metals within radiators and pipework from damaging the boiler. It works by coating the inside so the water doesn’t oxidise the metals.
How does a central heating system get corroded?
Water in the system reacts with metals in it, like steel in the radiators; aluminium, brass and copper in the boiler and pipework. If the system water has a higher or lower pH value than the ideal (between 6.5 and 8.5), it will corrode the metals causing rust and limescale which damage the radiators and the boiler, causing leaks and failure.
Can inhibitor be used on all central heating systems?
Inhibitor can be used on both pressurised systems such as with combi boilers and also unpressurised heating systems like the feed and expansion tanks. The method of application would be different but will help both types.
How to apply inhibitor to the central heating system?
Generally, if you have an open vented heating system, drain some water out of the tank, usually in the loft, and add the inhibitor to the feed and expansion tank. With a sealed system, you can add it through a radiator using a suitable filling kit (link to Amazon). Always follow the manufacturer’s instructions when adding inhibitor.
How often should inhibitor be changed?
Central heating inhibitor level should be checked at least once a year, preferably during a service and topped up if required. It will also need to be added again if you have drained the system down for some reason (like removing a radiator) and then replenished the water as the inhibitor will be lost.
How to test how much inhibitor is in a system
Testing the level of inhibitor is done by taking a sample of water from the central heating system (not water from the hot tap) and adding it to a solution provided in a testing kit. Checking the colour concentration will determine if the level is satisfactory or more inhibitor needs to be added.
Manufacturers generally have testing kits only for their products and it is best to use the same testing kit for the inhibitor used. But if you don’t know what inhibitor was used, you can use a universal test kit.
Is inhibitor mandatory?
Currently, adding inhibitor and checking of its level in a central heating system is highly recommended but it is very likely to become mandatory soon especially as modern boilers are more compact with smaller components, and warranties (some up to 12 years) won’t be valid without a satisfactory inhibitor level in the system.
Best central heating inhibitor products
Check out the following most popular products used in the industry. All available from Amazon:
CosWarm CW1 Central Heating Inhibitor and Protector
*The information in this article should be used for general guidance only. Always discuss your requirements with a competent and suitably qualified professional before undertaking any work.
