Nobody likes lukewarm coffee, especially from a coffee machine that should serve it piping hot. So, why would a coffee machine fail to get hot enough?
A coffee machine won’t get hot enough if the heating element is faulty, the thermostat isn’t functioning correctly, and the warming plate is rusty or dirty. Besides that, your coffee machine will deliberately not heat up enough if the High Altitude mode is enabled. The target temperature is lower in that mode because water’s boiling point is lower at higher elevations.
This guide will walk you through the possibilities affecting your coffee machine. You’ll learn why it’s not getting hot enough, why these problems happen, and how to fix each one.
Why Is My Coffee Machine Not Hot Enough?
Here are a few leading reasons why your coffee machine isn’t getting hot enough:
Faulty Heating Element
About this: Making coffee requires hot water to extract flavors from the coffee beans or grounds. That’s only possible with the coffee machine’s heating element that can quickly boil water for that purpose.
The heating element serves a dual purpose for coffee machines with a warming plate. Primarily, it boils the water to make coffee. However, it also keeps the warming plate hot enough to keep your coffee at an ideal drinking temperature.
The heating element is part of the water’s journey from the tank. As the water flows out of the tank and through the hoses, it passes through a heating element which raises its temperature significantly.
That heating process happens quickly, so your coffee machine can produce a hot cup in just a minute or two.
What happened: The first and most likely reason your coffee machine isn’t getting hot enough is a problem with the heating element.
More specifically, your heating element only failed partially. So, while the machine is generating heat, it’s not getting nearly as hot as it should be.
How to fix it: Heating elements are not the kind of components in your coffee machine that you can fix. So if yours is not performing exactly as designed, your solution is to replace it with a new one.
Thankfully, replacing it is pretty straightforward. You can disconnect the existing heating element from its electrical connectors and simply plug the new one in the same way.
Connect with an Appliance Repair Tech
Click here to use the chatbox to speak with one of our technicians.
No in-home service calls. No appointments.
About this: Coffee machines regulate their temperature using one or more thermostats. A thermostat senses the water temperature in your coffee machine.
When the water’s not hot enough, it triggers the heating element to turn on. Then, when the target temperature is reached, it shuts the element off.
What happened: A faulty thermostat will prevent your coffee machine from getting hot enough. That’s because it’ll mistakenly sense that the water is hot and shut off the heating element too soon.
As a result, the coffee machine never gets hot enough to make a perfect cup of coffee.
How to fix it: There’s some good news and bad news about faulty coffee machine thermostats. The bad news is you can’t fix one when it stops functioning correctly.
The good news, however, is that you can replace it yourself. You’ll have to open the coffee machine’s panel to access the internal components.
Then, disconnect the wiring to the thermostat before removing it. Lastly, install and connect the new, functioning thermostat.
High Altitude Mode Is Enabled
About this: When you live at a higher altitude, the boiling point of water is reduced. In other words, you don’t have to heat water up so high to get it to boil.
Coffee machine manufacturers know that and work it into their product designs. That’s why many models come with a High Altitude mode that heats the water to a reduced temperature.
That mode saves energy by lowering the target temperature for boiling water. So, the machine’s thermostat will shut off the heating element sooner than it usually would if the mode wasn’t activated.
When at higher altitudes, that reduced temperature is enough to boil the water and make a fresh cup of coffee.
What happened: If your coffee machine isn’t getting hot enough, the High Altitude mode is activated. The machine could have come out of the box with that mode enabled, or someone might have unknowingly turned it on.
When that’s the reason your coffee machine won’t heat enough, there’s nothing wrong with the coffee machine. The machine is behaving exactly as it was designed to.
How to fix it: The solution to this problem is very straightforward. You only have to turn off the High Altitude mode.
The precise steps will differ depending on your coffee machine’s brand and model. For example, some might have a dedicated High Altitude button on the control panel. In contrast, others might require you to press a sequence of buttons instead.
Rusty or Dirty Warming Plate
About this: As you read earlier, many coffee machines use their heating element for two reasons simultaneously.
Firstly, the heating element boils the water that passes through it. At the same time, it also heats a warming plate that keeps the coffee carafe hot for several hours.
In other words, the heating element helps the coffee machine make hot coffee but also helps to keep that coffee hot for an extended period.
What happened: The last reason your coffee machine isn’t hot enough is that the warming plate has become dirty or rusty. That means the plate isn’t transferring heat efficiently and is, therefore, not as hot as it should be.
Here’s another way to look at it:
Your coffee machine is producing hot coffee precisely as it should. However, the rusty or dirty warming plate fails to maintain the coffee’s temperature, leaving it lukewarm.
How to fix it: Firstly, try your best to clean the warming plate thoroughly. That’s effective enough for removing most warming plate stains, which typically consist of dried-up coffee spills.
Unfortunately, a rusted warming plate must be replaced with a new one. The rust blocks heat from transferring through effectively, so your coffee machine will never be hot enough until you replace it.
Frequently Asked Questions (FAQs)
Need a bit more help? Here are a few more common questions and answers:
Does Elevation Affect Coffee Brewing?
Yes, elevation affects coffee brewing. The boiling point of water is lower at higher temperatures. So, you don’t have to heat water as much to brew coffee. Check your coffee machine for a High Altitude mode to boil the water automatically.
How Do I Put My Keurig In High Altitude Mode?
Switch your Keurig coffee machine off, but keep it plugged into the wall socket. While it’s off, press and hold the ‘strong’ and ‘8 oz’ buttons simultaneously until you see them flash 3 times. When those buttons flash, the High Altitude mode has been enabled.
Can You Reheat Coffee In A Microwave?
Yes, you can reheat lukewarm coffee in the microwave. However, reheating coffee releases more of its various acids, making it more bitter and negatively affecting its taste.
Can You Replace The Warming Plate On A Coffee Maker?
Yes, you can replace the warming plate on a coffee maker if that model is designed for that. Also, you must ensure that you can get a new warming plate from the manufacturer to replace the one you already have.
How Do Coffee Makers Heat Up Water So Fast?
Coffee makers can boil water quickly by forcing it through a small metal tube where the heating element is. Because that tube only allows a small volume of water to pass through at a time, the water heats up much quicker than trying to boil a whole pot of water.