Product Overview
Table Of Contents
- Code No. LIT- 1927110
- Issued February 1, 2009
- A28 Series
- Two Stage Temperature Control
- A28AA-4
- The A28 Series are two stage temperature controls that incorporate a liquid filled sensing element.
- Use for temperature sensing applications requiring two-stage control of HVAC/Refrigeration equipment.
- Selection Charts
- 2-SPDT
- 30 to 110 (-1 to 43)
- 3 1/2 (1.9) Ea. Stage 3 (1.7) Fixed Between Stages
- 1-3/8 in. x 2-1/4 in. Coiled
- -
- Convertible
- 2-SPDT
- 20 to 80 (-7 to 27)
- 3 1/2 (1.9) Ea. Stage 3 (1.7) Fixed Between Stages
- 3/8 in. x 5 in. 6 ft Cap.
- WEL14A-603R
- Knob
- 2-SPDT
- 30 to 110 (-1 to 43)
- 3 1/2 (1.9) Ea. Stage 2 to 7 Adj. Between Stages
- 12 ft averaging bulb 6 ft Cap.
- -
- Screwdriver Slot
- 2-SPDT
- -30 to 100 (-34 to 38)
- 5 (2.8) Ea. Stage 2 to 7 Adj. Between Stages
- 3/8 in. x 4 in. 8 ft Cap.1
- WEL14A-602R
- Convertible
- 2-SPDT
- 40 to 90 (4 to 32)
- 3 Ea. Stage 2 to 7 Adj. Between Stages
- 3/8 in. x 5-3/4 in. 6 ft Cap.
- -
- Knob
- 2-SPDT
- 60 to 140 (16 to 60)
- 5 Ea. Stage 2 to 7 Adj. Between Stages
- 3/8 in. x 4 in. 6 ft Cap.
- WEL14A-602R
- Knob
- 2-SPDT
- 20 to 80 (-7 to 27)
- 2 Ea. Stage 2 to 7 Adj. Between Stages
- 3/16 in. x 22 in. 6 ft Cap.
- -
- Knob
- 2-SPDT
- 20 to 80 (-7 to 27)
- 3 1/2 (1.9)
- 3/8 in. x 5 in. 6 ft Cap.
- WEL14A-603R
- Screwdriver Slot
- 2-SPDT
- 60 to 90 (16 to 32)
- 5 (2.8)
- Strap-on Grid Bulb 42 in. Cap.
- -
- Screwdriver Slot
- Concealed adjustment
- Visible scale
- Knob kit
- Maximum bulb temperature of A28AA-37 is 230˚F (110˚C). For all others, maximum bulb temperature is 140˚F (60˚C).
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. © 2009 Johnson Controls, Inc.
www.johnsoncontrols.com
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Two Stage Temperature Control (Continued)
Technical Specifications
Maximum bulb temperature of A28AA-37 is 230°F (110°C). For all others, maximum bulb temperature is 140°F (60°C).
Replacement Parts
Code Number Description
CVR28A-617R Concealed adjustment
CVR28A-618R Visible scale
KNB20A-602R Knob kit
Electrical Ratings
Motor Ratings VAC 120 208 240 277
A28AA, A
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 7.2
Pilot Duty – 125 VA, 24 to 277 VAC
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1. When used as two circuit control, the total connected load must not exceed 2000 VA.
A28AJ
AC Full Load A 6.0 3.4 3.0 ---
AC Locked Rotor A 36.0 20.4 18.0 ---
Non-Inductive or Resistance Load A
(Not Lamp Loads)
15.0 9.2 8.0 7.2
Pilot Duty – 125 VA, 24 to 277 VAC
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A28AB
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 7.2
Pilot Duty – 125 VA, 24 to 277 VAC
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