Most places serving coffee get their hot water for tea and Americano’s from their espresso machine. This is quiet convenient. But there are several problems with this method.
If your aim is to serve high quality delicious drinks, including Amerciano’s and tea, and of course thats your aim, then using the hot water from an espresso machine isn’t really the device to use. The water from a double boiler espresso, such as La Marzocco, comes from the steam boiler. A steam boiler typically operates at 120c to 130c. They are also on typically half full of water and the rest is steam pressure which allow you to steam milk. So although your steam boiler may have a capacity of 7 liters, its actual water capacity is about 4 liters. Its a similar story for heat exchange machines, but it has further effect on these machines in that it effects the brew temperature. As you draw hot water out fresh cold water enters, instantly effecting the pressure in the HX boiler and therefore steaming capability, hot water temperature and brew temperature.
The hot water coming out of a La Marzocco Linea’s hot water tap can be around 100c. We ran some tests on our showroom Linea, pulling water for tea. The temperature exiting the spout was 99.8c. We find an acceptable drinking temperature to be 60-65c. We then timed how long it took to reach 60-65c. After 16 minutes it had reached 63.5c. This seems like an eternity when you want your coffee in the morning! And even then it tastes burnt and bitter.
That is why so much steam and hiss occurs when you pull hot water for tea and Americano. And 100c water doesn’t do any favors to coffee or tea.
It also puts a great deal more work and strain on the various components of your espresso machine. The elements, solenoids, contactor’s and relays all work overtime if your pulling hot water constantly from your espresso machines. But above all your serving your customers poor quality drinks. It can take 30 minutes for an Amerciano to cool to acceptable drinking temperature. It also adds unpleasant acidity and a burnt taste.
More modern La Marzocco espresso machines have a mixing valve where a small box with a valve mixes cold water with the super heated water from the steam boiler giving a more desirable hot water temperature. While this is admirable it doesn’t reduce the added stress to the espresso machine and is not temperature stable at all. It tends to be cool at the beginning then heats up slowly.
A much better solution is a hot water tower. The latest model from Bunn has digital temperature control, solid state relay and is extremely temperature stable. Has a digital to display to let you know the temperature of the water. A hot water tower will give you as much hot water as you want, at the temperature you want.
Leave the espresso machine for espresso!!
















