Product Overview
Table Of Contents
- Features and Benefits
- Application Overview
- Installation
- Wiring
- Models A25CN and A25CP
- SPDT (Single Pole Double Throw) Units
- Models A25AN and A25AP
- SPST (Single Pole Single Throw) Units
- Checkout Procedure peration
- Models A25AN and A25CN
- Return Air Applications
- Supply Air Applications
- Models A25AP and A25CP
- Dimensions
- Repairs and Replacement
- Table 1: Ordering Information
- Troubleshooting
- Table 2: Troubleshooting Chart
- Specifications
4 A25 Series Warm Air Control with Manual Reset Product/Technical Bulletin
C
heckout Procedure
After installing the A25, perform the following
procedures. Observe at least three complete
operating cycles to verify that all components are
functioning properly. If the unit fails to checkout, refer
to the troubleshooting chart (Table 2). Do not attempt
to make adjustments.
Return Air Applications
1. After completing the installation and wiring
procedures, turn on the power to the circuit.
2. Turn the setpoint knob counterclockwise until
the A25 shuts down the system.
The A25 should lockout and the alarm or
signal (if applicable) should activate.
Note: The setpoint at shutdown should equal the
approximate duct air temperature.
3. Turn the setpoint knob clockwise to the
desired setpoint.
Nothing should happen.
4. Press the reset lever.
The system should restart and the alarm or
signal (if applicable) should shut off.
Supply Air Applications
1. After completing the installation and wiring
procedures, turn on the power to the circuit.
2. Raise the supply air temperature to the
setpoint temperature.
Note: The supply air temperature can be raised
by simulating a fan failure or restricting the
return air flow.
3. When the system shuts down, determine the
temperature at the A25 sensing element.
The temperature reading should closely
approximate the A25’s setpoint at which the
system is shut down and (if applicable) the
alarm or signal is activated.
4. Return the system to normal operation by
re-establishing air flow or by restarting the fan.
5. Press the reset lever.
The system should restart and the alarm or
signal (if applicable) should shut off.
O
peration
Models A25AN and A25CN
Setpoint Adjustment: Adjust the A25 setpoint by
rotating the setpoint knob (Figure 7). The setpoint
is displayed in the setpoint window.
Test Procedure:
To test (trip) the A25: Raise the temperature
at the sensor above the setpoint or lower the
setpoint below the ambient temperature.
The
control should lockout (trip).
To reset after test: Lower the temperature at
the sensor to 20F° (11C°) below the setpoint or
raise the setpoint to 20F° (11C°) above the
ambient temperature. Press the reset lever.
The A25 should reset (closing the circuit).
Reset Procedure: Verify that the temperature has
dropped to 20F° (11C°) below setpoint. Press the
reset lever to reset the A25 (closing the circuit).
Figure 7: Models A25AN and A25CN