ℹ
info Honeywell
Status HOLD indicator
Indicates that a temperature is being held indefinitely, such as when on vacation.
? What Causes This
User pressed Hold Temp function to maintain current temperature setting.
ⓘ What This Means
Press Run Program key to cancel the hold and return to normal programming.
Source: page 16 of the official manual
From the manual
This error code appears in:
Honeywell CT3355 Home Programmable Thermostat