Sometimes, as a plumber, I received complaints that their heated towel rail was not working properly. Or, in private houses, heating radiators do not work effectively. Naturally, the first step is to pay attention to the violation of the circulation of the coolant in these devices.
Perhaps the circulation pumps have served their time or the mud filters in the heating system are clogged, and it happens that the batteries themselves are "overgrown" and the heat transfer efficiency has dropped because of this. In a heated towel rail, circulation is disturbed due to narrowing of the flow area by growths, even on products made of non-ferrous metals and stainless steel.
In urban apartment buildings, every year, in the summer, the heating system is flushed and pressurized. Thus, washing out deposits that interfere with the normal circulation of the coolant. Therefore, we do not consider such a system.
And our gaze will be directed at apartment towel dryers made of non-ferrous metals and heating registers made of aluminum alloys in private houses. With the help of an ordinary or neodymium magnet, it turns out that you can understand how much these devices are clogged without removing.
How to do it? I will show using the example of a conventional home dryer connected to a central hot water supply:
It is made of colored metal, therefore, any magnet should not stick to it.
We bring a neodymium magnet from the old hard disk to the surface of the specimen under study.
In horizontal areas, our "device" does not stick to the surface. But on turns, a magnetic connection is created and the magnet sticks, there are detailed photos in the gallery.
Any plumber will tell you that sludge likes to be deposited in pipe bends. It is clearly seen here that the physics of this process has been preserved.
This method can be safely used to detect magnetite deposits in heating equipment made of non-ferrous metals. Let's say in heating radiators.