TradeAssistIQHome

Mitsubishi Ecodan fault LL

Setting errors of DIP switches on FTC control board

Heat pump

What it means

Incorrect setting of DIP switches related to boiler operation or 2-zone temperature control.

Likely causes

  1. Incorrect setting of DIP switches
  2. Outdoor unit abnormal stop triggers automatic backup operation

Where to start

  1. For boiler operation, check that DIP SW1-1 is set to ON (With Boiler) and DIP SW2-6 is set to ON (With Mixing Tank)
  2. For 2-zone temperature control, check DIP SW2-7 is set to ON (2-zone) and DIP SW2-6 is set to ON (With Mixing Tank)
  3. Check OUT1 (Water circulation pump 1, Space heating/cooling & DHW) at TBO.1 1-2, connector CNP1.

The full answer, free

  • 35 more checks in order
  • The readings and component tests from the manual
  • How to put it right, step by step
  • The manual page for this fault (page 50), right under the answer
Ask about LL freeCreate a free account

Safety: Isolate the outdoor unit and any backup heater, and give the inverter capacitors time to discharge before you open the electrics. Anything on the refrigerant circuit needs F-gas certification.

From the Mitsubishi manual for the Ecodan. Check the model on the data plate before you order parts.

Other Mitsubishi Ecodan fault codes