A dirty coffee machine makes bad coffee. It's that simple. But we've seen plenty of well-meaning staff do more harm than good because nobody actually showed them what to do. So here's a straightforward cleaning schedule you can stick on the wall next to your machine.
Every day
This is the non-negotiable stuff. If you do nothing else, do this.
Backflush the group heads. Pop a blind filter into the portafilter, add a small amount of espresso machine cleaner (about half a teaspoon - check the packet), lock it in, and run the pump for 10 seconds. Release and repeat 4–5 times until the water runs clear. Then do it again with just water to rinse out any residue. Do this for every group head.
Clean the steam wands. Wipe them down after every use - that's a given. But at the end of the day, soak the tips in hot water with a drop of milk system cleaner. Milk residue builds up fast and it's a hygiene issue as well as a taste one.
Wipe everything down. The drip tray, the group head area, the portafilter baskets, the outside of the machine. Use a damp cloth with a bit of machine cleaner, then a clean cloth to dry. Don't use washing-up liquid - it leaves a residue that'll taint the coffee.
Empty the knock box and clean it. Old grounds go sour quickly. Rinse it out properly.
Every week
Soak the portafilter baskets and shower screens. Unscrew the shower screens from the group heads (you'll need a flat-head screwdriver) and drop them in a bowl of hot water with machine cleaner. Leave them for 20 minutes, scrub gently with a nylon brush, rinse well, and put them back. Soak the portafilter baskets at the same time.
Clean the grinder. Brush out any grounds from the chamber and the chute. If you've got a doser, give that a proper clean too. Old grounds stuck in the chute will go stale and make fresh coffee taste off. Some people run a handful of grinder cleaning tablets through once a week - it works well and takes two minutes.
Deep clean the steam wand. If the steam wand tip is clogged, soak it in a dedicated milk cleaner overnight. If it's really blocked, you can use a pin to clear the holes - carefully.
Every month
Descale if needed. This depends on your water hardness. If you're in a hard water area and don't have a water filter (you should), you might need to descale monthly. If you've got a filter, every 3–6 months is usually fine. Use a descaler made for coffee machines - not vinegar, not a kettle descaler. They're different products.
Check the water filter. Most commercial filters need replacing every 6–12 months depending on usage, but check the manufacturer's recommendation. A blocked or spent filter does nothing, and limescale will quietly destroy your machine from the inside.
Inspect the gaskets. The rubber gaskets in the group heads wear out over time. If your portafilter isn't locking in as tightly as it used to, or you're getting coffee leaking around the edges, the gasket probably needs replacing. This is a quick job for an engineer.
When to call an engineer
Cleaning is maintenance, not repair. If you notice any of these, it's time to call someone:
- Water temperature swinging up and down
- Pressure dropping during shots
- Leaks from anywhere they shouldn't be
- Unusual noises (grinding, hissing, clunking)
- Coffee tasting consistently off despite fresh beans and a clean machine
We service commercial machines and we'd always rather get a call early than have to deal with a breakdown on a Saturday morning. If something doesn't seem right, get in touch - we'll tell you whether it's something you can sort yourself or whether it needs a visit.
The products you'll need
You don't need a cupboard full of cleaning products. Here's the short list:
- Espresso machine cleaner (powder or tablets for backflushing)
- Milk system cleaner
- Descaler (for coffee machines specifically)
- Grinder cleaning tablets
- A good nylon brush and a group head brush
- Clean cloths - lots of them
We stock all of these and they'll last a long time. A tub of backflush cleaner typically lasts a busy cafe 2–3 months.
Got questions about any of this? Give David a call. He's sorted out more machine problems than he can count and he'll give you a straight answer.