Will an airlock eventually clear itself?

Answered by Christopher Steppe

Airlocks in hot or central heating systems are a common issue that can cause frustration and inconvenience. Many people wonder if these airlocks will eventually clear themselves. While it is possible for airlocks to resolve on their own, it is not a risk worth taking. Let me explain why.

To understand why airlocks occur, we need to delve into the physics of the system. Airlocks happen when air becomes trapped in the water or heating system. This trapped air creates a blockage, preventing the smooth flow of water or heat. The reason for this is that the gas, in this case, air, is less dense than the water in the system. Therefore, it tends to rise and get trapped in high points of the pipework.

Now, there are instances where airlocks may clear themselves over time. This can happen when the air slowly dissolves into the water or is pushed out of the system by the pressure. However, this process can be slow and unpredictable. It may take days or even weeks for the airlock to clear, and there is no guarantee that it will happen at all.

In my personal experience as a brewer, I have encountered airlocks in my fermentation vessels. These airlocks serve a similar purpose, allowing gases to escape while preventing oxygen from entering the fermentation process. If an airlock gets clogged, it can lead to a build-up of pressure and potentially ruin the batch of . In such cases, I have never relied on the airlock to clear itself. Instead, I have always taken immediate action to resolve the issue.

The same principle applies to hot water and central heating systems. While it may be tempting to wait and hope for the airlock to clear itself, it is a risk not worth taking. The consequences of a blocked system can range from reduced heating efficiency to complete system failure.

So, what can be done to fix an airlock? One common method is to bleed the system by releasing the trapped air manually. This involves locating the bleed valve, often found at the highest point of the system, and opening it until water starts to flow instead of air. This process allows the air to escape, restoring the proper flow of water or heat.

Another approach is to use a circulation pump or power flush equipment to force the air out of the system. These methods can be more effective in tackling stubborn airlocks and ensuring a thorough clearing of the system.

While there is a possibility that airlocks may clear themselves over time, it is not a risk worth taking. The potential consequences of a blocked hot water or central heating system outweigh the patience required to wait for a self-clearing airlock. Taking immediate action by bleeding the system or using other methods to remove the trapped air is the best course of action to restore proper functioning and prevent further issues.