Johnson Controls A19A Type number matrix, Contact functions, Adjustment, Repair and replacement

2	A19A
	Issue 03/03/2003
Note	Note

These controls are designed for use only as operating controls. Where an operating control failure would result in personal injury or loss of property it is the responsibility of the installer to add devices or systems that protect against, or warn of, control failure.

The standard screwdriver adjustment can be converted easily in the field to knob adjustment. Also concealing of adjustment and scale is possible after installation.

SPDT contacts are standard on all models. Instruments have compact sizes. Types A19ACC and A19ADC have a trip-free manual reset . Reset button must be pressed and released. Contact cannot be blocked in closed position. All types have VDE and SEV approval.

To facilitate ordering, wholesaler codes have been added on some universal models.

All models are provided with a separate knob and sealing cap.

Type number matrix

Contact functions

Types A19AAC,	3		2
A19AAF, A19ABC,
A19BAC, A19BBC,
A19DAC		θ >

1

Fig. 1

1-2 closes on temperature increase

A19AAC capillary thermostat, fixed differential. A19AAF capillary thermostat, special close

fixed differential.

A19ABC capillary or immersion thermostat,

adjustable differential.

A19ACC capillary thermostat, lock-out low with manual reset.

A19ADC immersion thermostat, lock-out high with manual reset.

Type A19ACC

2	3
	θ <
	1

A19BAC space thermostat, fixed differential. A19BBC space thermostat, adjustable

differential.

A19DAC strap-on thermostat. A19DAF strap-on thermostat

Adjustment

1.Models “set low” (refer to cover label) The dial indicates the low switch point (1 - 2 open, 1 - 3 closed).

The high switch point (1 - 2 closed,

1 - 3 open) is obtained by adding the differential to the low switch point.

2.Models “set high” (refer to cover label) The dial indicates the high switch point (1 - 2 closed, 1 - 3 open). The low switch point (1 - 2 open, 1 - 3 closed) is obtained by deducting the differential from the high switch point.

Exception: Type A19ADC, dial indicates high switch point ( 1 - 3 closed, 1 - 2 open).

Fig. 2
1-2 opens on temperature decrease
Type A19ADC	2	3
	θ >
	1
	Fig.3

1-2 opens on temperature increase

Repair and replacement

Repair is not possible. In case of an improperly functioning control, please check with your nearest supplier. When contacting the supplier for a replacement you should state the type/model number of the control. This number can be found on the data plate or cover label.

Catalogue Section 1	© 2003 Johnson Controls Inc.
	Order No. PD-A19A-E