Specifications

AQUATROL Zoning System
212 customer.honeywell.com 70-6910
AQ254 Add-a-Temperature Injection/Mixing Expansion Control Panel
for Hydronic Zoning System
The AQ254 Add-a-Temperature Expansion Control Panel is used in
conjunction with an AQ250, AQ25A, AQ251 or AQ252 Control
Panel. It provides one additional loop temperature control
capability for the AQ2000 control panel it is connected to and
expands the total network capacity by up to 16 zones when used
with AQ255 and/or AQ257 zoning panels.
• Acts as an add-on Control panel to the Main (AQ250, AQ25A,
AQ251, AQ252) Control panel.
• Allows each of the 16 zones connected to it to be assigned to the
system's primary or secondary loop.
• Up to 3 AQ254 panels can be added to a Main (AQ250, AQ25A,
AQ251 or AQ252) Control panel.
• Mixed loop temperature is controlled by a variable speed injection
pump or motorized mixing valve connected to the AQ254.
• Intuitive programming interface and armchair programming (can be
programmed at your desk and taken to the job site “ready-to-install”)
• Customizable mixing control settings allow for greater level of control
and comfort.
• Zone synchronization through Zone of Greatest Demand control.
• Integral 38 VA transformer with self resetting electronic fuse.
Application: Expanded zone control and mixed loop temperature
control in a hydronic zoning system
Mixed loop target temperature is reset by either outdoor temperature
or calculated system load based on indoor temperature feedback
Mixing is target controlled by a variable speed injection pump or
motorized mixing valve
Dimensions, Approximate: 9 1/2 in wide x 8 in. high x 3 3/8 in. deep
(24 cm wide x 20.3 cm high x 8.5 cm deep)
Power Supply: 120V/60Hz
Electrical Connections (Line Voltage): Wire-clamp screw terminals,
Maximum 2 x 14 AWG each on line voltage terminals
Control and Zoning Panel Temperature Rating: 32 F to 130 F
(0 C to 55 C)
Thermostat Compatibility: AQ1000 Series 2-wire communicating
thermostats and most digital thermostats
Variable Speed Injection Pump Output: Triac modulated; 120 Vac,
2.1A, 1/6HP
Secondary Pump Output Rating: 120 Vac 5A, 1/3HP
Auxiliary Pump Output Rating: Dry contact output, 120 Vac/250 Vac
5A, 1/3 HP
Sensor Temperature Rating: -58 F to +230 F (-50 C to +110 C)
Secondary Loop Mixing (Supply) Design Temp Range: 70 F to 210
F (21 C to 99 C)
Secondary Loop Mixing (Supply) Max Control Temp Range: 80 F to
210 F (27 C to 99 C)
Secondary Loop Return Min Control Temp Range: 80 F to 180 F (27
C to 82 C)
Secondary Loop Mixing (Supply) Min Control Temp Range: 35 F to
150 F (2 C to 66 C)
B-B Communication Bus Terminals: Low voltage, Class II, 2-wire
polarity-insensitive, digital communicating link to other Control or
Zoning modules.
R-C Input (on Control and Zoning Modules): 24 Vac Class II (input
on Control and Zoning Modules)
R-C Output (on transformer): 38 VA, 24 Vac Class II
Operating Humidity Range (% RH): 5 to 90% RH, non-condensing
Weight: 3.9 lbs (1.8 kg)
Approvals:
Canadian Standards Association: CSA C/US Certified to CSA and
UL Standards, File No. LR76030
Product Number
Type of
Zoning
Devices
Controlled
Number of
Zones
Controlled
Mixing Valve
Floating
Output
(Com,O,C)
Mixing
Valve
Modulating
Output
Boiler Pump
Output Rating
DHW Pump/
Valve
Output
Rating Replacement Parts
AQ25242B Zone pumps
or 2-wire
valves (line
voltage)
4 24Vac rated
dry contacts
0-10 Vdc 120 Vac/250
Vac 5A, 1/3HP
120 Vac 5A,
1/3HP
AQ15200B universal injection/mixing
boiler reset module
AQ12C11 supply/return/mixed loop sensor
AQ12C10 outdoor sensor
AQ10X38 24 Vac 38 VA transformer
AQ15540B 4-zone pump expansion
module
AQ25244B Zone valves
with end
switches
4 24Vac rated
dry contacts
0-10 Vdc 120 Vac/250
Vac 5A, 1/3HP
120 Vac 5A,
1/3HP
AQ15200B universal injection/mixing
boiler reset module
AQ15740B 4-zone valve with end switch
expansion module
AQ12C11 supply/return/mixed loop sensor
AQ12C10 outdoor sensor
AQ10X38 24 Vac 38 VA transformer
Product Number
Mixing Valve Floating
Output (Com,O,C)
User Interface (Setting,
Programming) Replacement Parts
AQ25400B 24Vac rated dry contacts LCD Display and a 3 button
Key Pad
AQ15400B Add-A-Temperature expansion control module;
AQ12C11 supply/return/mixed loop sensor;
AQ10X38 24 Vac 38 VA transformer