Use pliers to destructively take off the Oetiker clamps on the boiler. This photo shows a different Oetiker clamp as I removed the ones on the boiler in a previous repair. You will need to buy some new 9 mm hose clamps instead. They can be fitted with a regular screw driver. You can go shopping while waiting for descaler to work.

You may need to twist, push or pull fairly hard to get the hoses off.