Decent Espresso

How to replace the DE1 AC Board



How to replace the DE1 AC Board


In this video, we'll walk you through how to replace the AC board.

You'll need to open the board room to access the AC board if AC-powered components are not functioning properly.

*Important: Do not open the board room or attempt to access the AC board without our guidance. The AC board carries high voltage.

This video is part of a series that we produce, helping people self-repair their Decent Espresso Machine.

  • Only do this repair in consultation with Decent tech support
  • Doing otherwise might break your machine or void your warranty.
  1. 00:05 Tools Needed
  2. 00:10 Power Disconnection
  3. 00:31 Remove External Components
  4. 01:12 Remove the Main Cover
  5. 01:35 Remove the Chassis
  6. 02:55 Remove the Back Panel
  7. 03:50 Disconnect AC Board Cables
  8. 05:33 Prepare Wires for New AC Board
  9. 06:08 Install the New AC Board
  10. 08:20 Secure the AC Board
  11. 09:01 Reassemble the Machine

Tools Needed

  • T10 Torx screwdriver
  • PH2 Phillips screwdriver
  • Adjustable wrench (XL/XXL only)
  • Pliers (Long nose pliers are recommended)
  • Nippers (for cable ties)
  • Comfort grip gloves (recommended)
  • Cloth (to protect the machine)
  • Cable tie

Step 1: Power Disconnection For XL or XXL Models:

  1. Remove the back panel.
  2. Turn off the machine's back switch.
  3. Unplug the power cord.

For Pro and Plus Models:

  1. Turn off the machine's back switch.
  2. Unplug the power cord.

For Version 1.43 or Higher (Slide-Type Tablet Stand):

  1. Unplug the USB cable.
  2. Gently pull the tablet stand out.

For Version 1.3 to 1.42 (Screw-Type Tablet Stand):

  1. Unscrew the three screws holding the tablet stand.
  2. Remove the stand.

Step 2: Remove External Components

  1. Remove the drip tray and drip tray cover.
  2. Lift the lever on the back and slide out the water tank.
  3. Remove the portafilter and group head handle.

Step 3: Remove the Main Cover

  1. Use a T10 screwdriver to remove the 8 screws on the main cover.
  2. Gently stretch the sides of the cover and lift it off.

Step 4: Remove the Chassis

  1. Check if the manifold screws are T10 Torx or PH2 Phillips.
  2. Remove the six screws securing the chassis.
  3. Unscrew the side screw of the boardroom lid (use an appropriate screwdriver).
  4. Remove the lid.

Removing the PSU Holding Chassis:

  • Older machines: 3 screws
  • Newer machines: 4 screws
  • Use the correct screwdriver (T10 or PH2).
  • Before removing the last screw, place a cloth under the machine leg to prevent scratches.
  • Gently place the chassis on the countertop.

Step 5: Remove the Back Panel For Pro Models:

  1. Remove the four T10 screws securing the back panel.

For XL or XXL Models:

  1. Remove the four standoffs using an adjustable wrench or pliers.
    • Alternatively, use a T10 screwdriver to press and turn the standoffs.
  2. Unscrew the intake pipe knob:
    • Lift the pipe slightly while holding the tube inside.
  3. Remove the back panel.

Step 6: Disconnect AC Board Cables

  1. Press the clip while pulling each cable to release it.
  2. Remove the ribbon cable (AC/DC board connection):
    • Hold the top and bottom of the connector head.
    • Gently wiggle it out.
  3. Unscrew the 5 screws securing the AC board (T10 or PH2).
  4. Disconnect power wires:
    • Use pliers to remove the red wire from the relay.
    • Use pliers to remove the black wire from the power switch.
  5. Remove the AC board from the machine.
  6. Disconnect the two-pin cable by pressing the clip while pulling.

Step 7: Prepare Wires for New AC Board

  1. Cut the cable tie on the black/blue tube T-tap connector using nippers.
  2. Release the latch and open the plastic casing.
  3. Remove the metal blade (with two wires).
    • (Wearing gloves helps grip the blade securely.)
  4. Pull the black wire out of the metal blade.

Step 8: Install the New AC Board

  1. Insert the metal blade back into the plastic casing (flat side facing the slot).
  2. Press the blade further until it slightly protrudes from the back.
  3. Place the black wire into the opposite side of the casing.
  4. Close the casing, tighten with pliers, and ensure the latch locks.
  5. Secure with a new cable tie and trim excess.
  6. Reconnect wires:
    • Plug the red wire into the relay (press firmly with pliers).
    • Reconnect the two-pin cable until it clicks.
  7. Place the AC board back in position.
  8. Plug the black wire into the power switch.
  9. Reconnect the ribbon cable:
    • Align holes/pins properly.
    • Press in until pins are no longer visible.
    • Verify all pins are fully inserted.

Step 9: Secure the AC Board

  1. Install the 5 screws on the back (T10 or PH2).
    • Slightly raise the board to align the first hole.
    • Tighten the first four screws halfway for alignment.
    • Insert the fifth screw, then fully tighten all screws.
  2. Reconnect all AC board cables (listen for clicks).

Step 10: Reassemble the Machine

  1. Reinstall the PSU holding chassis (avoid pinching wires).
    • Hold the chassis while inserting the first screw.
  2. Reattach the boardroom lid and secure with a screw.
  3. Reinstall the back panel:
    • Insert the refill water inlet barb connector.
    • Hold the panel while tightening the intake lever.

For Pro Models:

  • Tighten the four T10 screws.

For XL/XXL Models:

  • Reinstall the four standoffs (finger-tighten first, then fully secure with T10).
  1. Reattach the side panel:
    • Insert and tighten the first five screws halfway for alignment.
    • Fully tighten all six screws.

Final Check

  • Ensure all connections are secure.
  • If issues arise, contact tech support.

Done! Your AC board replacement is complete.

#acpcb #pcb #ac #DIY #repair #highvoltage #howto


  • Chinese (simplified): 如何更换 DE1 交流主板

    Updated 2025/07/29