Adjustment - PENN Controls - A19BAC - A28AA - Electromechanical Temperature Control - A19 Coiled Bulb Control - A28 and A36 Multi‐Stage Temperature Control

A19BAC, A28AA Single and Two-Stage Space Thermostats for Heating and Ventilation Applications Installation Guide

Product name
A19 Coiled Bulb Control
A28 and A36 Multi‐Stage Temperature Control
Document type
Installation Guide
Document revision
G
Revision date
2023-10-18
Part number
996-238

The range screw comes with a knob adjustment or screwdriver slot. The dial pointer is located on the adjustment stop bracket on the knob and screwdriver adjustment models.

Before you remove the cover, verify that all power to the thermostat and associated equipment is turned off.

WARNING
  • Risk of Electric Shock
  • Disconnect or isolate all power supplies before making electrical connections. More than one disconnection or isolation may be required to completely de-energize equipment. Contact with components carrying hazardous voltage can cause electric shock and may result in severe personal injury or death.
Avertissement
  • Risque de décharge électrique
  • Débrancher ou isoler toute alimentation avant de réaliser un branchement électrique. Plusieurs isolations et débranchements sont peut-être nécessaires pour -couper entièrement l'alimentation de l'équipement. Tout contact avec des composants conducteurs de tensions dangereuses risque d'entraîner une décharge électrique et de provoquer des blessures graves, voire mortelles.
Figure 1. Setpoint stop adjustment screw

To adjust the temperature set point stop of solid cover models, complete the following steps:

  1. Set the dial temperature to the required stop temperature.
  2. Remove the control cover.
  3. Loosen the cutout stop screw.
  4. Slide the screw to the front of the temperature control against the plastic step behind the dial.
    Note: Sometimes an exact stop setting is not possible and you must set the stop to the closest step corresponding to the dial setting.
  5. Tighten the screw.

In the field, on convertible adjustment models, you can change from concealed screwdriver slot adjustment to knob adjustment or external screwdriver slot adjustment. These models come with a snap-in plug in the cover to provide concealed screwdriver slot adjustment. For knob adjustment, remove the snap-in plug and press the knob onto the slotted shaft. For external screwdriver slot adjustment, remove the snap-in plug.

The A28AA switch is stamped to indicate the HI-TEMP switch and the LO-TEMP switch.