How to descale a polti AS700? It heats up well, but runs out of steam before the water. There is sludge in the bottom of the tank.

SOURCE: Polti Vaporetto 2400: Water out light comes on when tank is full

Hi you need to put 5ml of Kal Stop fo Polti machines into 1000/1500ml of water into the tank, The stronger solution is better (1000ml) Let it heat up and this should break down the limescale on the solenoid. I tried this today and it has worked saving ££££'s in repair by Polti.

SOURCE: polti 1500 no steam just droplets of water

hello, i had also the same problem.
i disconnected the hose. there is a small hole where the hose connects.
i put there a litlle screwdriver in few times in and out. and then the steam came.
the polti must be switched on and heated up before you de this.
be carefull, when you put the screwdriver in, the steam can come on your hands and face.

SOURCE: Bissell pro heat steam carpet cleaner, not releasing water.

That means that you need to replace the pump belt. Here is the belt you need and a manual you can view:

Bissell 7901 Belt and Manual

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