FieldBench
Mitsubishi codes

Mitsubishi

Pressure protect

Lockout

High / low pressure protect

Outdoor high- or low-pressure protection (token is on the MXZ door card for this revision — do not invent a City Multi number).

Walk Pressure protect in Diagnose

Sign in for the next measurement

First check

1 Airflow and freeze before you add gas

On Mitsubishi MXZ-SM low pressure / freeze is indoor airflow or a starved coil until proven otherwise. Filter, blower, dirty A-coil, closed supplies. In heat mode, a iced outdoor coil is the same family. Service valves open. Outdoor fan. All indoor blowers that are calling.

Expect: Indoor air moving. Coil not iced. OD coil clear in heat.

The rest of the walkthrough is Diagnose.

On the plates

  • Service valves open. Outdoor fan. All indoor blowers that are calling.
  • Weigh-in + adders. Do not ‘top off’ to a piston SH chart.
  • Restriction / drier / one indoor EEV stuck.

Plates that use Pressure protect