Brochure

Table Of Contents
The performance specifications are nominal and conform to acceptable industry standards. For applications at conditions beyond these specifications, consult the local Johnson Controls office.
Johnson Controls, Inc. shall not be liable for damages resulting from misapplication or misuse of its products. © 2015 Johnson Controls, Inc. www.johnsoncontrols.com
R-63
A28 Two-Stage Temperature Control with Weatherproof Enclosure
Description
The A28MA Controls are wide range
temperature controls with rainproof NEMA 3R
enclosure and two single-pole, double-throw
(SPDT) switches.
Refer to the A28MA Type Two-Stage Tower
Fan Control Two-Stage Air Cooled
Condenser Fan Control Product Bulletin
(LIT-125135) for important product application
information
Features
rugged steel enclosure
liquid-filled sensing element provides
uniform control
Applications
sump water temperature control for cooling
towers and evaporative condensers
fan cycling control for air-cooled
condensers
Repair Information
If the A28 Two-Stage Temperature Control with
Weatherproof Enclosure fails to operate within
its specifications, replace the unit. For a
replacement control, contact the nearest
Johnson
Controls®
representative.
Selection Chart
Product
Code
Number
Switch
Action
Range
°F (°C)
Differential
F° (C°)
Bulb and
Capillary
Range
Adjuster
A28MA-1C
Two-Stage
Two-SPDT
Switches
40 to 120
(4 to 49)
Factory set
5 (2.8) each stage
8 (4.4) between stages
3/8 in. x 4 in.;
Neoprene-coated 6 ft capillary
Screwdriver
slot
A28MA-2C 3/8 in. x 4-1/16 in.; 6 ft capillary
Technical Specifications
Note: When used as a two-circuit control, the
total connected load must not exceed
2,000 VA.
Electrical Ratings
Motor Ratings 120 208 240
AC Full Load A 16.0 9.2 8.0
AC Locked Rotor A 96.0 55.2 48.0
Non-Inductive or
Resistance Load A
(Not Lamp Loads)
16.0 9.2 8.0
Pilot Duty 125 VA, 24 to 277 VAC
A28MA Temperature Control
Multi-Stage Electromechanical Temperature Controls
Code No. LIT-1927125