Removing The Boiler

• Unplug machine.
• Remove only the water lines & wires attached to the boiler & thermostats and clearly mark them for easier reassembly. Taking some digital pictures will help you reassemble everything.
• For Classic & Coffee models, push the switches back through the case while depressing metal tabs on each side of the switch.
• Remove the four allen bolts attaching the boiler to the outer shell (located under the front edge where the portafilter is inserted).
• It may be necessary to remove the steam valve at the boiler, otherwise disconnect it from knob & steam wand.
• Lift out the boiler (it'll still have water in it).

Disassembling & Repairing The Boiler

• It's not necessary to remove any of the parts attached to the boiler.
• Remove the four allen bolts holding the boiler together and the boiler should split into two parts.
• The lower part (brass) usually needs little more than blowing out the water paths with compressed air.
• The upper half (aluminum) will probably need more work. A Dremel tool with a wire brush attachment will make short work of the mineral buildup.
• If there's more than minute corrosion & pitting on the mating surface of the aluminum half of the boiler it will require some attention.
  • I use a flat piece of aluminum plate that I glue different grits of emery paper to (spray glue works wonders).
  • I place the mating surface flat on the abrasive & move it  about in a non repeating motion.
  • I start with a fairly heavy grit & work my way down in steps.

Reassembling & Reinstalling The Boiler

• Once the inside of the boiler is clean reassemble the two boiler halves.
  • If the O-ring is still intact & pliable reuse it otherwise order a new one.
  • I lay in a thin bead of LocTite RTV silicone gasket sealer (NSF approved) & lay the O-ring on top followed by another thin bead of sealant.
  • Tighten the four bolts until you feel the resistance of the O-ring.
  • Stop & wait for the sealer to partially cure (read directions) before tightening the bolts completely.
  • The sealer usually needs to completely cure for 24 hours and after that you've got a seal that can withstand any temp & pressures an espresso machine can offer up. And I've been assured by the techies at LocTite that the sealant will resist incursion by mineral deposits, so your boiler should never leak.
• Reinstall the boiler, valves, water & electrical wires; using the reverse order that you removed them.
• Plug in the machine, grind some beans, dose, tamp & brew.

You'll think you have a new machine!