American Standard mini split error code Ed

Common causes

• A loose connector between the boards.
• A failed board.

How to fix it yourself

Do the reset and the visual checks, but the underlying repair needs a technician with a meter and the service manual.

1. Reset the system: switch the breaker (or the outdoor disconnect) off, wait a full five minutes so the boards fully discharge, then switch it back on and restart from the remote.
2. With power off, reseat the connectors between the outdoor boards.

Switch off power at the breaker before opening either unit. Capacitors in the outdoor unit hold a charge for several minutes after power is cut.

When to call a technician

Board-level fault.

Which American Standard units show Ed

This page applies to American Standard 4TXK / 4MXW / 4TYK hi-wall inverter and Mitsubishi Electric-built units units on the Mitsubishi Electric-built units. American Standard's own documentation lists Ed as "Serial communication error (outdoor unit boards)", the same definition used across the Mitsubishi Electric it is built on. If your unit shows a code with a different shape (for example a four-character code, or a plain number), it is from a different table; use the lookup with your exact code.

Where American Standard shows this code

Mitsubishi Electric-built units: Wall units without a wired controller signal a fault by blinking the operation indicator lamp; the code itself shows on a wired controller (MHK/PAR series) or on the wireless remote after entering its check mode (see your manual). On the outdoor unit, the control board LEDs blink the same code. P codes are indoor-unit faults, E codes are communication faults, F codes are outdoor-unit faults and U codes are outdoor-unit and compressor faults.

Other American Standard codes

Same part of the system as Ed:

All American Standard error codes

Ed on other brands

The same characters do not always mean the same thing. Check the brand on your unit.

• Mitsubishi Electric Ed Serial communication error (outdoor unit boards)