If you have identified the problem as being one of a mechanical nature, you can resolve the issue with an appropriate mechanical fix.
If the water is clear water, it suggests that the system is free from active corrosion, but does not eliminate the possibility that corrosion has occurred in the past.
As this is the final stage of corrosion, large deposits can be expected within the system. If there are black particles present in the water, these are most likely to be magnetite.If there is a reddish tinge to the water, it indicates that iron oxide is present, suggesting active corrosion.Examine it for suspended solids or discolouration which can indicate corrosion. Check if the boiler is operating correctly.This guide can help you to conduct checks which will lead to an accurate diagnosis of the circulation problem.
If your customers are experiencing poor circulation in their homes, such as ineffective radiators, it could be caused by hydrogen in radiators and so it is important to accurately identify the cause of the issue in order to properly resolve it.