If with water through wand with hot water switch depressed, then
- This noise could be from a pinched intake hose(s) from the reservoir to the pump.
- Solution: Unplug the espresso machine from the electrical outlet. Remove the top cover to check the hose(s).
- The hose is sucking up against the sidewall of the reservoir.
- Solution: Check the hoses in the reservoir while the problem is corrected.
- The pump rotated on its side and is rubbing against the frame.
- Solution: Unplug the espresso machine unit from the electrical outlet. Remove the top clever and back panel (2 inner screws into the black frame and the single screw in the slot of the platform under the reservoir). Rotate the pump.
If only happens when pressing coffee switch pressed in, then
- It may be a bad 3-way solenoid valve behind the front lower panel.
- Solution: Unplug the espresso machine from the electrical outlet. Remove the lower front panel. Inspect the valve. Disconnect 2 wires that are not yellow nor green. Place electrical tape over the connection. Power on the espresso machine. Hit the coffee switch for about 10 seconds max and power off. If the squeal goes away, the valve may be clogged (unplug from the outlet, reconnect wires, and backflush first). If the problem remains, the solenoid valve “may” need replacement.