Guide to choosing and maintaining a radiator

It sounds like magic: today, in relatively new apartments or renovated houses, you turn on the hot water tap and automatically, with no more effort than waiting a few seconds, the liquid appears lukewarm from the pipe. We know that this miracle – which many take for granted in their lives but which until a few decades ago was the luxury of very few – is generally produced by radiators, those white, rectangular and fiery devices, previously common in bathrooms and kitchens but now They are installed on loggias, patios or outdoors.

As long as it is doing its important job, hardly anyone cares about how a heater works or what needs to be done to take care of it. Until it breaks or it’s time to install a new one.

Marcos Alarcón, who has been a plumber for 25 years, took time out of his busy schedule to explain the science behind a water heater, which is actually not that complex.

“Inside they have a copper winding pipe, through which cold water passes, which is heated by a series of gas burners below, which are activated by flow when the pressure reaches a minimum ignition level,” he said.

It’s very simple: the burners raise the temperature of this intestine-shaped pipe, which causes the water passing through it to heat up on contact and come out steaming from our showers or our dishwashers.

That’s all? Not that much, because in order for them to work well, several characteristics must be reviewed which, depending on the particularities of our home, will make all the difference.

All water heaters run on gas. Although there are other methods and fuels for heating water in pipes – such as the increasingly common electric water heaters, which heat and store water using electricity – calefonts are still very popular. popular and all use this type of energy.

But there are two kinds of gas: natural, which is supplied by pipes directly to homes, and liquefied petroleum gas (LPG), which is obtained from the famous balloons or bottles. The type of heater we buy will depend on the type of gas we use at home. “It’s very important to know,” says Carlos Manríquez, construction professor at Duoc UC Alameda. “There are equipment compatible with natural gas and others with LPG”, he adds, but there are no devices that work for both. “Pipe gas is denser than liquefied gas,” says Alarcón, “and using the wrong heater can damage equipment and be very dangerous.”

The second most relevant feature is the “literature” of the heater. This figure – which ranges from 5 liters (the smallest) to 32 liters (the very, very large) – reflects the number of liters the device can heat per minute. If it is 7 liters for example, it means that in one minute the temperature of 7 liters of water can rise by 25 degrees.

Why are liters important? “Because if there are dishwashers, sinks and a shower in a house, and there are about four people, you will need a water heater of at least 10 liters to be able to heat this volume of water”, explains the plumber Alarcón.

Manríquez shares a chart that explains well the relationship between liters and water demand. “If I want to supply hot water only to a dishwasher and a sink – for example, in an office or business – a 5-litre water heater will be optimal. But if I add a shower, there is one with a bigger capacity”.

The first water heaters, created at the beginning of the 20th century, were installed in the same bathrooms, which caused a pleasant shower but enormous pollution, very risky for health. The gas, when burned, releases large amounts of CO2, which then remains in the environment. Now things have changed and, according to regulations, all such devices must be installed “by personnel qualified by the Superintendence of Electricity and Fuels (SEC)”, explains Professor Duoc UC, to ensure that carbon monoxide ventilation is correct.

To remedy this inconvenience, there are forced draft radiators, which have an integrated fan that expels the gases. Thus, these models can be installed inside houses or apartments without risk of contamination. “They can use a duct at 90º, which allows gases to be evacuated even from a space without windows”, explains Manríquez. “But these are more expensive and exclusive,” warns Alarcón.

Not like the natural draft ones, the classic ones that have a vent tube right above them. They expel the gases vertically, following the heat emanating from the burners. Current Chilean regulations only allow the installation of this type of heating in open spaces such as loggias, patios, balconies or terraces.

Today they are no longer on the market – the regulations prohibited them a few decades ago – but for a long time the radiators, with the famous pilot light, were lit manually, with a match, a lighter or a candle. Something that made you go out and turn it on during freezing winter mornings, cold and sleepy.

Of course, there are still such models in many houses and apartments, but anyone who wants to change or buy a new radiator will only find technological devices that turn on automatically when the water is turned on.

These can be ionized (which need batteries to work), those that contain a microturbine (they don’t use batteries, since they generate energy internally) or those that plug into the electricity grid .

“Today, moreover, water heaters are stuffed with sensors,” explains plumber Alarcón. It refers to different mechanisms to control water temperature, flow rate and the amount of CO2 they emit. All of this is for the benefit of the user; for example, “an ionized model does not have a pilot flame and for this alone they allow a saving of gas calculated at around 7 kilos per month”, as Manríquez tells it. Nothing bad.

But at the same time, they are “more complicated to repair than before”, complains Alarcón. In the past, the same things failed, like the passage needle, but now that they are electronic, they bring a lot of plastic, for the same reason, they are more disposable”.

Unfortunately, says the teacher, “the radiators are not for life: they have an average lifespan of 10 years, although a lot depends on the maintenance we can carry out”.

With this, he refers to the famous “once a year interview”, something that is preached everywhere but very few practice. This intervention should only be carried out by a licensed plumber – some brands include this service in their price – and it is necessary to clean the radiator and avoid any damage.

“Maintenance consists of changing rubber parts, graphitening – applying a graphite paste that lubricates the different parts of the equipment – ​​and cleaning impurities.” Airborne dust that moves due to dirt and other environmental contamination soaks into the interior of heaters, impairing their operation.

But something users can do to extend the useful life of water heaters is to install a filter next to the drinking water meter. “The water in Santiago is too hard,” they both say, causing scale buildup in pipes and coils. “In Maipú there are even more minerals; there, many people use filters, because otherwise the devices last less,” adds Alarcón.

When does a radiator show signs of deterioration? “As the parts wear out, corrosion develops or the coils start to leak,” says Manriquez. “You can also realize that it loses pressure and therefore does not heat the water because of the hardness of the water.” In all these cases, an authorized and specialized technician must be called.

*Prices for products in this item are current as of April 8, 2022. Values ​​and availability may change.