Here is an extract from the user guide you will have got at the time.
Descaling
It is impossible to advise about the frequency of descaling as this is dependent on the water hardness (lime scale)
and usage of the machine. Even if you use bottled water of a low mineral content or filters/filter jugs, eventually
the machine will require descaling. The only system that completely removes the need for descaling is softening,
or Reverse Osmosis with remineralisation using non scaling ions. Descaling should be performed by a qualified
service agent, so we only give broad guidance for the procedure.
The Boilers are low corrosion AISI 316L stainless, so will not be damaged by descaling solution and the copper
pipes feeding the group have such thick walls, it also won’t be a problem.
Service Boiler Descaling
This is the easiest boiler to descale. Switch on the service boiler; bring the machine up to full steam pressure
(whatever you have set). Place a container under the water wand, switch the machines power off and in stages
open the water tap and empty the service boiler. When you can draw no more water, the service boiler will be
completely empty. You will get approximately 1400ml of water from the service boiler
Place a descaling solution in the cold water tank approx 50g - 100g citric acid (always add acid to water) to 1
litre of water, dissolve the citric acid in a little warm water before adding cold water to make up to the volume
required. Switch the Minima on with service boiler heating enabled. The service boiler should start refilling
(do not touch the coffee brew switch unless you intend to descale the brew boiler as well). Add more
descaling solution to the cold-water tank as necessary. Allow the service boiler to come up to full pressure
and then switch off, leave the machine for 3 hours. Remove the water tank wash it out and refill with clean
water and replace in the machine.
Switch the machine on, once up to to full steam pressure (whatever you have set). Place a container under the
water wand, switch the machines power off and in stages open the water tap and empty the service boiler. You
will get approximately 1400ml of descaling solution and you should see evidence of descaling action. Be careful
the solution will be hot and acidic, do not get any in your eyes (or wear safety goggles).
Switch the machine on again and it should start to refill with clean water from the tank. Repeat this
emptying and refilling process twice, or until no more taint of descaler remains.
Brew Boiler Descaling
You can use two methods, whatever you decide, it is important to prevent the service boiler from refilling unless
you plan to descale that as well. So, don’t use any water from the service boiler, make sure the service boiler is
off and cool if you only want to do the brew boiler.
1. Easy method - Put a strong descaling solution in the cold-water tank (top up with new descaler as necessary)
100g per litre of citric acid, as before dissolve in a little warm water (always add acid to water) before adding
cold to make up 1 litre. Run this solution into the brew boiler by operating the brew switch. 30 seconds on/30
seconds off. Do this about 6 or 8 times until the water coming from the group smells strongly of descaler. Do not
have the portafilter loaded for this and use a container to catch the solution coming from the group.
Leave the machine on for a couple of hours, clean the water tank and replace the descaler with fresh water.
Repeat the flushing of the group as before, but with fresh water until no taint of descaler remains. Expect
to have to flush through around 15 litres or more to achieve this.
2. Hard method (only for experts, so no detailed description) - Unplug machine and open top, remove
temperature sensor without damaging wiring, it uses PTFE tape on the threads(so comes off easily). Use large
syringe and tube to evacuate brew boiler of water. Use same syringe to fill brew boiler with descaling solution 50g
-80g per litre (it will take around 800ml). Replace temperature sensor, bring brew boiler up to temperature and
leave for 2 hours. Unplug machine, allow to cool remove temperature sensor and use syringl to remove all
descaler. Fill with clean water and remove, repeat once more. Refill with clean water, replace temperature sensor.
Taste water from group to ensure all descaler removed, otherwise flush a few times.
This is a light descale, it’s better to descale more often than do a much deeper descale with specialist
chemicals. It is very important to use a damp microfibre cloth and wipe of all splashes of descaler from
the stainless steel surface of the machine and group to avoid damage. Regularly rinse the cloth out.
