Applicable Systems
Carrier ComfortLink Thermostat/Controller

Symptoms

High pressure switch open. The discharge pressure has triggered the high pressure safety switch.

Possible Causes

  • Condenser airflow restricted or fan failure
  • Refrigerant overcharge causing excessive pressure

Troubleshooting Steps

  1. Step 1: Check the condenser fan operation and airflow
    Fan is not running or airflow is restricted
  2. Step 2: Verify the refrigerant charge level
    Charge level is above specification

How to Reset

To reset: Fix the airflow or charge issue, then reset the controller.

Source: Carrier HVAC Troubleshooting Guide, Carrier Corporation

Category: HVAC Residential