ℹ
info Honeywell
Status Heat On / Cool On flashing on the screen
Compressor protection feature is engaged — the system is waiting 5 minutes before restarting to protect the compressor from damage.
? What Causes This
Recent mode change or power cycle on a heat pump system.
ⓘ What This Means
Wait 5 minutes for the system to respond safely and restart without damage to the compressor.
Source: page 10 of the official manual
From the manual
This error code appears in:
Honeywell Set Temp RTH5160 Thermostat