Switch-activated override - PENN Controls - LIT-12012249 - A421ABT - A421AET - Electronic Temperature Control - A421 Duty‐Cycle/Ventilation Models

A421 Series Electronic Temperature Controls with Cycle Timer Product Bulletin

PENN Controls
Product name
A421 Duty‐Cycle/Ventilation Models
Document type
Product Bulletin
Document number
Revision date

When you close a switch between the BIN and COM terminals of the TB3, the control is overridden, and the fan relay remains on. The fan relay remains on until the circuit (toggle switch) between BIN and COM is open.

The relay remains energized regardless of the sensor value, sensor fail state, or any timing parameters (cP, Ont, Ltt). The control display alternates between the main display and manual override (Ord).