What is a central heating inhibitor and do you need it?
The central heating inhibitor is something that you don’t realise how much you need it. It is the backbone of everything and ensures that your system is running as efficiently as possible. Most people don’t know what an inhibitor is or what it can do to prevent sludge build up, breakdowns or repairs in the long term.
It is essential to have a heating system working efficiently. Most boiler manufacturers will state that your warranty may be void if the heating system doesn’t have the right inhibitor levels.
So, let’s take a look at what a central heating or radiator inhibitor as it is sometimes called is and why is it important?
What is a Central Heating Inhibitor?
The central heating inhibitor is a chemical solution that protects your central heating system. Along with things like a magnetic filter, it also helps to keep you boiler system running efficiently, which can prolong its life span.
Inhibitor is made up of a mixture of potassium tetraborate tetrahydrate, disodium molybdate, sodium nitrate and 2,2′,2″-nitrilotriethanol. It can be either clear or pale yellow in colour.
What does an Inhibitor do in Central Heating?
Radiator sludge is a result of a mixture of dirt, scale, and rust that builds up over time in your central heating system. This thick gloop forms at the bottom of your pipes and radiators, preventing water from flowing properly through the system and allowing radiators to heat up efficiently.
Here’s where the inhibitor steps in. The inhibitor’s chemicals work together, and the chemical reaction reduces the sludge buildup in your central heating system. When use in conjunction with a magnetic filter, these can really help keep your metal pipes clear for years and years.
Is a central heating inhibitor required?
A central heating or radiator inhibitor is not only essential to ensure your pipes and radiators are in good condition, but it can also protect your heating system from damage.
We also mentioned that your boiler warranty could be voided if you do not use the inhibitor. It is an integral part of a central heating system that works properly. Let’s now see how to add it into your system.
What is the right amount of Central Heating Inhibitor to use?
To ensure that the inhibitor is able to be pumped around, you need to use the entire bottle. It is typically about one liter. However, it all depends on how concentrated the inhibitor is and how many radiators are used. To ensure you use the correct amount, we recommend that you always read the instructions on the back of your inhibitor bottle.
Is it possible to add too much inhibitor?
The simple answer to this question is no. It is impossible to add too much inhibitor in your central heating system. Doing so will not cause any harm. Your system will be protected even further by adding more inhibitor.
How to Add an Inhibitor to Your Central Heating System
It is easy to add an inhibitor to your central heating system. Don’t be afraid to try it if you’ve never done it before. There are several ways you can do it, depending on the type of heating system.
The majority of people in the UK own a combi boiler system. We will first show you how to use it, then we’ll go over the other methods.
How to Add an Inhibitor to a Combi Boiler Systems
Make sure you turn the heating off
Before you move on to the next step, make sure that your radiators have cooled completely. Once you have done this ensure you drain the whole system before adding inhibitor.
here is our quick guide on how to drain your heating system to add inhibitor, and prevent boiler breakdowns and costly repairs.
Start draining the system by finding the central heating drain valve.
The drain-off valve can be found on the lower part of the plumbing pipes or on an exterior wall.
Remove the adaptor and tighten the plug back up. You should not tighten the valve too much as this could cause damage to the ‘O” ring.
Turn the radiator valve back on. Turn the valves anti clockwise to open them. Unscrew the radiator valve. You can remove the bleed plug with a spanner.
Attach the Chemical inhibitor dosing pipe. Some brands include a dosing connector with the bottle that can be attached to the radiator plug. You can also use a funnel or flexible tube if you don’t own an adaptor.
Add inhibitor by pouring it in
Slowly pour the inhibitor in the funnel or dosing adaptor. You only need to put the inhibitor in one radiator.
As you have been amending the amount of fluid it may e a good idea to check the boiler pressure. You can add more water to increase the pressure or let some air out of your radiator valves
Normal boiler pressure is approximately 1.5 BAR. However, if in doubt, refer to the manufacturing guidelines.
At this point, it is a smart idea to bleed radiators using the bleed valve at the same time.
How do I add a chemical inhibitor to a closed system
- Most central heating systems are now closed. If your heating system has an expansion vessel, you can add the inhibitor via the filling loop to the radiator. It is possible to drain water from the system prior to adding the inhibitor. Water cannot be displaced within a sealed system.
How do I add inhibitor to an open vented system?
You will need to add the inhibitor to the larger tank if you have an open-ventilated system that has a large water tank and an expansion tank. Before you turn the water off at the mains or the valve on the tank, you must first verify that you have done this. Also, make sure that your tank is clean and free of corrosion. It should be cleaned if it appears to need it.
How often should the central heating inhibitor be changed
The central heating inhibitor can become less effective over time. This means that it cannot do its job correctly and provides enough protection against sludge and limescale.
The inhibitor usually lasts about a year. Your heating engineer should test the system, and then add the inhibitor to the system during an annual service. You can test your radiators yourself if they take too long to heat up.
These home kits can be used to measure the concentration of inhibitors in your system.
If you have just drained your system to flush out a radiator, for example, then you should add more inhibitor.
You may also need more inhibitor if you have a recent leak in your boiler. This is because the pressure increases the chemical concentrations and decreases protection.
Which is the best central heating inhibitor?
The central heating inhibitors are made in a similar way so it is difficult to compare them. It is best to always read the back of the Inhibitor to see what their use is with various central heating systems. Most boiler companies recommend Fernox and Sentinel as the 2 inhibitors they prefer for efficiency.
While Fernox F1 is the most popular, Sentinel is also very popular. Although your heating engineer might have a preference they all will get the job done.
You may not be sure which inhibitor you should use.
You probably agree with this statement that central heating inhibitors are crucial. It is crucial for a healthy heating system. However, there are some other things that you can do to ensure your boiler’s longevity and system protection.
Ways to protect your central heating system
Flush your radiators
You need to think about this: If you have been adding inhibitors to your system to break down the dirt and sludge, there is a way out!
Fushing radiators is the best method to do this. Or, you can book a power flush to your heating engineer to get rid of all the gunk.
Install a magnetic boiler filter
Magnetic filters are great for protecting your boiler because they capture all metal bits and broken down sludge, before it reaches the boiler to cause any damage.
These tiny filters are very useful and should be cleaned at least once per year.
Add a limescale reducer
Magnetic filters, as good as they may be, are not capable of removing limescale. Your scale reducer is here!
Limescale can cause serious damage to your system, and expensive repairs will be required. It’s a smart idea to invest in a scale reducer, which will save you money over the long-term.
Check boiler pressure regularly
Ensuring your boiler is at the right pressure will mean that your boiler is running effiiciently. If you are taking all the other steps and spending money on extras to lower costs, one free way to do it is to ensure the water pressure is at 1.5bar.
Take Care of Your Central Heating Inhibitor
It is easy to forget common sense, but it can be crucial when working with boilers and other pressure-focused appliances. You should be aware of the dangers and how to avoid them, whether you’re mixing different types of inhibitors together or making your own inhibitor from different chemicals.
If the boiler is low in pressure, it could be leaking. Adding more water to the solution can make it even less effective. It is better to fix the problem first, especially after you have added the inhibitor.
It is important to note that no matter the type of inhibitor or brand, you should not consume it. Also, be sure to clean up any spilled liquids.
Keep Your Warranty in Mind
No matter what brand or model, the warranty on your boiler and heating system can be extremely useful. You might be able to get replacements for certain components or faults, and they may also provide specific information. It might be easier to find a registered engineer at a lower cost.
Each brand has its own warranty options. While some brands may offer warranties for up to ten year, others might only provide a one- or two-year warranty. You will be able to understand the appliance you have purchased and use it to your advantage to save money or get better service.
Although they may offer a warranty, these are usually short-term. You might be eligible for a refund if the mixture doesn’t work properly or the container does not connect to the radiator correctly. Make sure you read the warranties before you use them.
Choosing the right central heating inhibitor?
Choosing the right central heating inhibitor can be a bit of a guessing game but we always say to check with your Gas Safe registered heating engiener if you are unsure. If you are getting a brand new boiler we recommend you get this as part of your boiler installation package.