So, I figured it was time to descale my Butterfly Hx. The reason I figured I needed to do this was because it is an old 2nd hand machine (age unknown). The guy I bought it from said it had a new pump (it didn’t) and he said he replaced the seals in the group head (he hadn’t) and he said he had given it a really good descale … I went with the trend…!

I based my “technique” on the sticky thread in this forum but modified it in a couple of unique ways as per below

- Turn machine on and bring up to pressure
- Turn machine off and empty boiler via hot water tap & boiler pressure
- Empty water reservoir and fill with 2 litres of descale solution
- Turn machine back on and, leaving the steam wand open, fill boiler to full until water comes out the wand.
- Trigger earth leakage circuit when water comes out the vacuum valve
- Turn power back on in the house.
- Turn Banana’s in Pyjamas back on for my son
- Close the steam valve & turn the machine back on
- Go toilet
- Come back to the machine to see descale solution pouring all over the bench from the hot water tap (that wasn’t closed earlier)
- Close the hot water tap & turn the machine off
- Clean up descale solution which had gone into all the drawers under the bench where the coffee machine was
- Notice all the vinyl wrap on the drawers has been damaged by the hot water
- Wash all the dishes that got covered in descale solution
- Do the clean cycle (steam wand / group / hot water tap / wait / repeat) as per instructions in sticky until the boiler is empty.
- Refill the boiler to the top with the steam valve open.
- Trigger the earth leakage circuit again
- Reset the TV for my son again
- Turn the machine back on with a lot of paper towels around the vac valve to catch the water coming out
- When the machine is up to pressure empty the boiler using steam wand & hot water tap & running water through the group head to flush the thermosiphon circuit
- Consider doing things slightly differently this time:
o Allow the boiler to re-fil to its auto level.
o When the boiler has heated up and is at pressure then bypass level probe and open steam vent to allow more water in
o Watch boiler pressure and stop filling before vac valve retracts
o Once the pressure comes up again then start to overfill again
o Keep doing this until water comes out the steam valve without the vac valve retracting
o Yay, no more tripping the RCD
- Empty boiler as instructed again
- Repeat flush using boiler pressure reference method one more time
- Done…

I suggest you don’t follow all the steps above when descaling your Hx. I would suggest monitoring the boiler pressure though to prevent overflow