I was in college when I thought it would be a great idea to take apart my espresso machine to see how it worked.
I’m not sure what I was thinking – maybe I was trying to save money on coffee or just figure out where this gurgling noise came from.
Anyway, the machine was a mess after I took it apart. The worst part was that it didn’t work anymore. In the end, I had to buy my first espresso machine.
Still, the good news is I can now share with you the secrets behind your coffee machine.
Skip to the best part:
How do coffee machines work?
There are many ways to make coffee, but the most common type is drip-coffee makers. These work by filtering water through grounds before delivering it onto your cup – eliminating all of those pesky cleanups you had with other kinds!
Water reservoir (water tank)
Let’s start with the water reservoir. This tank stores the water until it is heated during the coffee-making process.
Depending on the size of the machine, the water reservoir can hold anywhere from two to twelve cups of water. This is an important feature, as it allows users to prepare multiple cups of coffee without replenishing the water supply. Additionally, the water reservoir helps regulate the water’s temperature, ensuring it is hot enough to extract the maximum flavor from the coffee beans.
Hot water pipe
The second component is the tube that contains hot water. It is an insulated tube that runs from the bottom of the machine to the faucet situated at the very top of the assembly. We’ll talk about this heating process in a moment.
The faucet makes up the third component. It is essentially a little “showerhead” placed above the coffee grounds. Its purpose is to transport the hot water through the hot water tube and spray them over the coffee grounds. It ensures that all the coffee grounds are saturated.
Of course, Drip Coffee Machine is not a drip coffee machine without a drip, right? What lies between the coffee and the faucet is the drip area. A little plastic disc with perforations regulates how quickly water drips into the coffee grounds below.
So, how does the cold water in the reservoir turns into boiling hot water from the faucet? There’s a pipe with cold water connected on one end to a hole in the bottom of the reservoir. On the other, it is connected to a tube within the heating element. This component takes cold water and passes them through the heating element.
The heating element consists of a resistive heating element and a tube used to transport water. A pipe connects these two sections. Aluminum is employed in its construction, and it is put to use in the process of heating the water. It is responsible for connecting the cold-water tube to the hot-water pipe and performing all the work.
A one-way valve guarantees that the water moving through your coffee maker will always follow the route intended for it to go in at all times.
The resistive heating element is positioned between the metal warming plate under your coffee pot and the aluminum water tube that runs through the middle of the coffee maker.
The warming plate is covered in a layer of white grease, placed between the resistive heat element and the warming plate. This helps transfer heat uniformly across the warming plate, which maintains the ideal serving temperature for your coffee. You must practice extreme caution if you come into contact with this grease.
How does this drip coffee machine work?
The heat source will warm up as soon as the user turns on the coffee maker. After that, the water inside the metal tube will start to boil. When water is warmed to a boil, bubbling of enough size forms to drive the water upwards through the hot-water pipe, then through the coffee maker, and finally out the faucet. Some scalding water can splash over the coffee grounds as it is sprayed from the tap. By saturating the coffee grinds with hot water, you can release the scent and flavor of the coffee into the coffee pot waiting for it.
How Espresso Machines work
After my poor experiment with dismantling a coffee machine, I never had the guts to take a real espresso machine apart. Nevertheless, I did have the chance to learn quite a lot about how these machines work, so let me share my insights.
What processes are carried out precisely within an Espresso machine? And how can one learn about their business without sifting through a dense undergrowth of technical jargon? Using water as an example, I will follow its path through the machine, starting from where it first enters the machine and ending with the finished result, which is Espresso.
Water reservoir or plumbing connection
Water is a necessary component for the operation of any espresso machine. Water can enter a home espresso machine in two ways: through the machine’s internal reservoir or a permanent plumbing connection.
The machine’s intended function often dictates the water supply. Coffee makers with the capacity to make only a few cups of high-quality Espresso or lattes per day typically include reservoirs.
A reservoir allows you to start with water of a higher quality than what comes out of the tap, which is a huge convenience.
A good water filtration pitcher can perform a great job of transforming tap water into drinkable water that satisfies SCAA standards.
A stable water supply is necessary for bigger households and light commercial devices designed to create hundreds of beverages daily. These appliances are hardwired into your home and connect to preexisting water softening and filtration systems. The reservoirs in these machines never need to be refilled, which is a huge time saver.
Home espresso machines In most modern espresso machines, manual pumps have been replaced by electric ones. A vibratory pump and a rotary vein pump are examples of electric pumps that a home espresso machine can utilize.
The vibration pump, also referred to as the vibratory pump, is a miniature electromagnetic workhorse. A piston attached to a magnet is housed inside a metal coil.
The quick movement of the piston caused by the magnet in a back-and-forth motion forces the water to move through the espresso machine. This movement is made possible by an electrical current that runs through the coil. The average frequency of a vibe pump is approximately sixty pumps per second.
The heating element
Let’s begin with the most crucial part, the heating element. The boiler is the component of a machine that generates heat. The water must first be heated and then subjected to pressure if you want a rich, flavorful espresso. But what about PIDs and maintaining a consistent temperature? What is the main distinction between a single boiler and a dual boiler?
The pressure water transferred to the boiler from the pump is first heated and then held at that temperature. A wood fire was the energy source for the first espresso machines. The temperature of the water in modern machines is typically achieved through the use of electric heating elements. Heating elements are not particularly intelligent on their own. The majority have a simple on/off operation: when they are turned on, electricity circulates through the element, producing heat; when they are turned off, they are unresponsive.
It is essential to give some thought to the dimensions of the boiler. If the boiler is bigger, then the machine can make a greater quantity of beverages. On the other hand, the amount of time and energy required to heat all the water will increase proportionally with the size of the boiler.
Even with all of the intense pressure and heat, producing Espresso is a delicate art; even minor variations in the water’s temperature can significantly impact the flavor of your shot. A large number of manufacturers have released a variety of new tools to improve temperature stability and user control.
A pressure stat calibrates more specific heating components to a predetermined temperature. These heating elements are typically found in more affordable and compact espresso machines. The problem with using simple heating components to heat water is that they give the user very little control over the temperature of the water. Because of this, it will be more challenging to get shots that are consistent time after time.
A boiler equipped with digital temperature control is utilized in the brewing process so that the brew’s temperature can be precisely controlled. Both models permit the user to adjust the temperature of the brewer in increments of one degree. They will maintain the temperature with minimal variation once it has been set.
For a machine to be able to extract shots and steam milk at the same time, it needs to have the ability to heat water to two different temperatures at the same time.
Dual boilers and heat exchangers
A machine that acts as a heat exchanger is one such solution. The boiler only heats the water for steaming as opposed to boilers heating the water for both steaming and brewing.
From the pump, an additional water line is routed, and this line ultimately connects to a heat exchanger made of copper that runs through the body of the boiler. The heat exchanger, The water in the heat exchanger is heated by the steaming water in the steam boiler. Still, the water in the heat exchanger does not boil. In a system like this, the water for brewing will never be close to the water for the boiler.
The use of a heat exchanger confers several advantages over the use of a single boiler. The machine can draw shots and steam milk at the same time because the brew water boiler is separate from the steam boiler. Unfortunately, using a heat exchanger makes it more challenging to maintain a consistent temperature for the brewing water. If left for too long, the brewing water in the exchange coil can reach an unsafe temperature. Because of this, it is essential to bleed or purge a tiny amount of water immediately before brewing Espresso with a heat exchanger. This is a technique that is referred to as temperature surfing.
A Dual Boiler is an answer for espresso-making devices designed to produce large quantities of beverages and have the necessity of steaming and brewing simultaneously. Within this type of machine, two different boilers receive water from the pump. The first bring the water to a boil, while the second gets it to a temperature suitable for brewing. Most machines with a dual boiler will have a digital temperature controller to precisely regulate the temperatures of both boilers.
As a result of the additional boiler and heating elements that have been incorporated into the design, the cost of these machines will be significantly greater. One of the advantages is that it is possible to manufacture a large number of beverages while retaining a considerably higher level of control over the amount of steam and Espresso that is generated. This is one of the benefits.
How to operate an espresso machine?
To sum it all up, here’s how an espresso machine works from the user’s point of view:
It all starts by adding water to the reservoir and activating the device.
The water in the heating chamber will begin to heat up instantly, and the machine will notify you when it has reached the ideal temperature and pressure.
You then need to remove the portafilter from the machine to load it with the required quantity of finely ground coffee. After tamping the coffee firmly and evenly, place the portafilter back and lock it.
After getting everything ready, place a little cup under the spout so it may collect the Espresso when it is finished.
Now, you are ready to start brewing your Espresso. Press down on the button or valve to activate the machine. The water will be forced out of the heating element and through the coffee grounds. This will create a delicious cup of Espresso for you to enjoy.
How to operate a milk frother of an Espresso machine?
You will have to follow a few additional steps if you wish to heat some milk to add to your Espresso:
First, purge the steam wand to release air and water. Then put the needed amount of milk into a jug, and place it under the steam wand so that the cup is completely submerged in the milk.
Now activate a valve in the heating chamber. The steam from the boiling water will be released to heat and froth the milk.
To fully learn the art of milk frothing, check out our post about how to froth milk on an Espresso machine.
So which is better, a coffee maker or an Espresso machine?
Most coffee drinkers worldwide agree that espresso machines produce a superior cup of coffee. Coffee can be adjusted to suit your mood, taste, or desired strength in an espresso machine.
On the other hand, coffee makers only serve one purpose, so the coffee they brew is guaranteed to be weaker. You might expect to enjoy the espresso machine’s final result more if you are a coffee connoisseur.
How do Coffee Machines work – Some final thoughts
Coffee is essential to my morning routine. Without it, I would be completely unable to function. Therefore, when I got intrigued about how my coffee machine works, I did what I had to do to learn how they operate.
Coffee makers and espresso machines make the process of brewing coffee more straightforward. While it may seem to be a straightforward process, the equipment in your device requires quite a bit of inventiveness to turn water into coffee successfully.
I hope you better understand how they function and appreciate these miraculous machines more.