Boiler
When to open the boiler
Gaggia's manual does not cover this, and its safety booklet says repairs are only for a service centre authorised by Gaggia. The retailer Whole Latte Love opens the boiler for four reasons: a crack from frost, a leaking boiler seal, heavy scale, or a three-way valve that keeps blocking. Its rule: light scale is cleaned off and the boiler reused; pitting means a new boiler.
The boiler is sealed to the group by one O-ring (167, EPDM). The retailer says the same seal fits the aluminium and brass boilers and should be renewed every time the boiler is opened.
The brass boiler is sold as a complete assembly for 120 and 230 V. Whether its heating elements can be replaced separately is not stated by Gaggia.
Clear the top of the boiler
A retailer's method (Whole Latte Love), done with the boiler in the machine. The retailer says it is the same for aluminium and brass boilers. The fuse, its bracket and the hose are placed by eye in this model.
- Unplug and let the machine go cold. Take the top cover off and push the three buttons out forwards.
- Undo the wand's nut with a spanner and lift the wand out.
- Photograph the wiring. Pull off the heater wires and the steam thermostat's wires, and lever the brew thermostat's two connectors off.
- Undo the fuse bracket's screw on top of the boiler and lift the fuse aside without bending its leads.
- Squeeze the spring clip on the hose at the top of the three-way valve, slide it up and pull the hose off.
- Take the steam valve off: two screws, 5 mm hex.
Lift the boiler and fit the seal
The retailer's method, continued.
- Crack all four boiler screws with a 5 mm hex key, then undo them. Leftover water runs out as the joint breaks: tip the machine forward over a sink.
- Lift the boiler out. The old seal stays on the boiler or in the group's groove. Throw it away.
- Clean the loose scale out of the group's well and off the dip tube, so none can reach the three-way valve.
- Fit the new seal, lower the boiler and start all four screws before you tighten any.
- Tighten them in a cross pattern, then go round again firmly so the seal is compressed.
- Refit the hose and clip, the steam valve with a new O-ring, the wand, the wires, the fuse, the buttons and the cover. Refill and load the circuit before heating.
If the thermostats move to a new boiler, steam goes on top and brew on the side: see replace a thermostat.