When was the last time you stopped in your tracks to have a good look at a radiator? There’s one in almost every room you’ll ever be in. For many people, there’s a certain mystery about them that almost makes it seem like they just magically work to heat rooms.
But what are some interesting facts about radiators that the average person might not know? Well, strap in as I blow your mind with some radiator facts that’ll have you looking at radiators like never before.
Radiators do not really radiate
Let’s take a quick journey back to your physics class in high school. If you can remember learning about the different ways heat can be transferred, radiation occurs when thermal energy is transferred through waves (e.g. heat from the sun). This doesn’t happen at all with radiators.
They will use convection to transfer heat, as it is done through the air in the room. Convection occurs when particles gain heat energy and movement. It’s why the air above the radiator is always going to be warmer than the air below. There is some radiation happening, but it is really convection which gets things going, although I don’t think people would be interested in suddenly referring to them as “convectors.”
Radiator valves have secrets
There are two types of radiator valves you can have. Manual radiator valves typically have a small-cap with the valve connected underneath. When you turn one on and off, you’re trying to control the amount of hot water coming in so your radiator will be just how you like it.
The second type (which holds all the secrets) is the thermostatic valve. It is the one which will have numbers or a gauge on the bottom you turn to get to a specific level. The secret behind it, and what makes it different come manual valves, sits in the cap top of the valve.
When you pick a number for the valve, you’re telling it you want the room (not the radiator) to get to a specific temperature. So how does it know when to stop the water? There is a capsule hidden inside which works like a thermometer. Once the valve hits the temperature you’ve asked, the capsule will expand like a balloon and push down a pin through the valve, which then blocks any new hot water from coming in.
If the room starts to get colder, the capsule will contract and let some new water in. It’s a nifty trick, and one most people don’t know about.
Radiators have hidden design features
Ever see a radiator with indents on the front, or a fin stuck in the middle, and wonder why it is even there? These are examples of design features made to improve how efficiently a radiator works.
How so? It all comes down to the surface area a radiator has. Imagine your radiator was one big solid chunk on the wall with no holes. It wouldn’t be able to let air pass through, warm up, and circulate around a room. Now, if you just had a big gap between the panels, air would pass up properly, but it would be dependent on either side of the panel to heat up. When there’s a fin running through the middle, you’re massively increasing the amount of cold air which can be heated as the fins cover a bigger surface and can trap a larger amount of air (that’s why they’re sandwiched in the middle and not in front of the radiator).
Radiators hate warm air
If a radiator is supposed to create hot air, how can it hate it? If I were talking about the outside of the radiator, then we’d be ok, but it is the air on the outside that causes problems. The paint on the outside acts as a protective layer to help prevent oxidation, which then leads to rusting.
When the air gets trapped on the inside, it creates pockets where the oxygen from the hot water can escape and latch onto the exposed material (usually steel). If enough air gets trapped over time, the inside of the radiator will corrode, and bits of rust will chip away. It won’t create a hole in the radiator, but it will create some sludge build-up which can get passed through pipes to other radiators and create more blockages, which when leads to more corrosion.
How do you stop it? Well, always make sure to bleed your radiators once in a while or get yourself an air valve which does it automatically.
Now you’re a radiator expert!
Thanks for reading this article on radiator secrets. I hope it has taught you a thing or two about how radiators work and why they are a surprisingly nifty piece of engineering.
