You need:

The solution for cleaning.
I like to use 1/4 cup per half gallon of water, its easier math. A 1/4 cup is the same as 4 tablespoons. And the homebrew shop packages are 1/4 cup each. So no measuring either.

2 gallons of water: 1 for cleaning, 1 for rinse
I like to use distilled water. I figure why descale with hard water. Also it will still trip the over fill because of the addition of the citric acid to the distilled water.

A Sponge or rags.
You need something to soak up stray water inside the machine if you get any.

Tools:
Phillips screw driver, allen wrench, needle nose pliers.

A large pitcher, bucket or sink:
If you don’t have a drain in your drip dray you may need a bucket or a sink nearby. You will be flushing lots of water.

Lots of time.
The total process takes a few hours.

Now is the time to make that last shot because you are going to have one for a while.

Turn off the machine if it was on. Open up the machine in the normal method. This will be kind of a pain because the top part of the machine has to be connected to the bottom body.

You can just flip the top over on its top to the left of the machine. This leaves the switch wires in easy access. If you are using the normal tank you can put it inside the area where it would normally go. The pump water lines should still reach into the tank.

The tank holds the switch on to make it heat up and fill the tank, etc. without water the switch doesn’t let the machine operate. You need to over ride this somehow. I used to just get a piece of wire the same gage as the switch wires and jump the switch with it. Later on I started using an external tank that is behind the machine. I can open it up without needing to remove the tank. I used to put a weight in there to hold the switch closed. Then I realized I could change how the switch works. If you move the wires to a different position you make the switch on when its up and off when its down. While the machine is off you need to choose a method that works for you, and make it so.

Grab the probe with needle nose pliers and hold it in place while you unplug the wire that is attached to it. Reconnect the wire but leave it loose so you can easily disconnect it without moving the probe, be careful to not move it by grabbing it with the needle nose pliers any time you mess with this connection.



(I don’t ground the auto-fill because I couldn’t figure it out and also because I never am trying to only descale the HX. IMO grounding the probe is only needed if you don’t want it to auto fill and put citric acid in the boiler.)

Fill the tank with the cleaning solution. Or you can mix it in a gallon jug, then cut off the top of the jug so you can get the water softener thing and the lines from the espresso machine in there.



Turn on your machine and let it come up to full temp.

Turn off machine and open hot water valve. You have the machine off so it won’t refill yet. Let all the water come out of the boiler. I like to leave the front on during this step. In fact you don’t really need to remove the front.



Turn the machine on. It will refill with the descale solution. Let the machine fill up completely and come up to temp. I like to let another big draw from the hot water tap. This will get some descale solution into that area as well as get some more into the tank to make sure its fully filled with lemony goodness.

descale the HX by drawing a big flush of the descale solution. Turn on the brew pump and flush 8-10 or more ounces of descale solution. Taste the water to make sure it is lemony. Note the time and move on.

it is time to overfill the boiler. Turn off the machine and unplug the probe wire. Be careful to not move it by grabbing it with the needle nose pliers.

With the probe wire disconnected. Open the steam wand, make sure it is pointing in to a pitcher or drip tray. Turn the machine back on, the boiler will begin to fill. It will take some time but eventually liquid will come from the steam wand. When this happens, turn off the pump and close the steam wand. Reconnect the probe wire without moving the probe.

wait an hour with the machine on and at full operation temp, flush the HX again. I like to use a white coffee cup to catch this water, and trip out on the blue green color.



wait another hour and do the HX flush again because that water was cool looking.

another hour makes three hours of hot descale soaking.

you can wait probably up to 4 hours but I usually cant wait that long or end up needing to leave or something.

to rinse it out do everything over again except using that extra gallon of clean water you have. You don’t have to wait the hours in between. You still need to overfill the boiler and make the clean rinse water come out the steam wand. Flush the HX until its no longer blue and also no longer tastes like lemon.

bring the machine to temp turn off the machine and open the hot water valve.

turn machine on let it fill. Repeat #14 until the water is not lemon tasting.

over fill the boiler the way you did before. Rinse rinse rinse.

clean up when everything no longer tastes like lemon.

turn off and unplug the machine.

replace the connection on the probe really well. Careful to not move it.

clean up any water inside the machine.

replace the switch connection on the safety tank to the desired orientation.

close it all up and plug it in.

turn on the machine and let it come to temp.

you have descaled your espresso machine.

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