Goodman

LPS

Lockout

Low pressure / freeze

Suction dropped out — charge, indoor airflow, or TXV.

4 plates — walk the one on the cabinet

First check

1 Airflow and freeze before you add gas

On Goodman GLXT7C 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. Indoor filter, blower, coil freeze. Do not add gas on a frozen coil.

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

The rest of the walkthrough is Diagnose.

On the plates

Indoor filter, blower, coil freeze. Do not add gas on a frozen coil.
TXV / restriction. Weigh-out if the history is a leak.
Low ambient and wind can nuisance-trip LPS on a light load — still prove charge.
Heat mode: outdoor coil iced, outdoor fan, defrost not running. Do not add gas on an iced outdoor.
Cool mode: indoor airflow, freeze, TXV.
Weigh-out if the history is a leak. LPS on a heat pump is not automatically ‘low on 410A.’
Charge / leak. Filters and indoor coil first — a dirty rooftop ices like a starved piston.
TXV / orifice. Economizer dumping 40 °F OA on the coil can look like a freeze-stat trip.

Plates that use LPS

Same number, other makers

LPS on Goodman is not the same code on these plates.