Troubleshooting - PENN Controls - LIT-125118 - A25AN - A25CN - A25CP - Electromechanical Temperature Control - A25 Warm Air Limit Control

A25 Series Warm Air Control with Manual Reset Product/Technical Bulletin

PENN Controls
Product name
A25 Warm Air Limit Control
Document type
Product Bulletin
Technical Bulletin
Document number
Part number
Document revision
Revision date
Table 1. Troubleshooting chart
Symptom Problem Solution
The A25 is not sensing properly. The sensing element may not be extended into the airstream or the sensing element is contacting an object inside of the duct (or plenum). Insert the sensing element as far as possible into the airstream without allowing it to contact any object inside the duct (or plenum).
The system does not operate. Incorrect switch connections or improper wiring.

Damaged sensor.

The A25 is tripped.

Ensure that the wiring connections follow the wiring diagrams in the Wiring section.

Check connections.

Replace the A25.

Reset the A25.

A25 does not lockout upon a temperature rise beyond the setpoint. The A25 is defective. Replace the A25.
The A25 does not sense the correct air temperature. The A25 is defective. Replace the A25.
A25 will not reset. The temperature in the duct (or plenum) is not 20F° (11C°) below the setpoint. Check system for overheating or fire.