Honeywell AQ25A Series Technical Reference Booklet page 290

Control Panels
All AQ2000 Control Panels provide sophisticated management
of Domestic hot Water Tanks (DhW) including:
• DHW priority and DHW priority override
• Internal Set-point - No need to set boiler target temperature
when there is a DHW call
• DHW Vacancy Setpoint - For vacation homes, DHW and
space heating zones can be set to energy saving setpoint with
one switch (Aux-In)
• Option to use the Return sensor as DHW sensor - Can be
used to control DHW setpoint
4 ZONES + 1
6
– Multi-Zone Systems (continued)
AQ252 Reset Control Panel For
Multiple Temperatures
All the Great Features of the AQ251 Outdoor Reset Controller Plus:
• The ability to control 2 water temperatures (boiler loop and mixed
• Expandable up to 64 zones and 5 reset water temperatures by using
AQ254 Add-A-Temperature Injection/
Mixing Expansion Panels
Works with any AQ2000 Control Panel each AQ254:
• Adds the capacity for an extra "reset water temp" to any AQ2000 network
• Expands the network capacity by an additional 16 zones
• Can add up to 3 AQ254 panels to an existing AQ2000 boiler control panel
The AQ2000 allows you to use all of your space heating zones for just that!
No need to use one of those zones to run your DHW.
temperature loop) with injection pump or motorized mixing valves
AQ254 panels
Model Number Application
AQ2524M2 For use with pumps or zone valves without
end switches
AQ2524M4 For zone valves with end switches
Model Number Application
AQ2541E0 Expands an existing AQ2000 installation
by up to 16 zones and adds an additional
controlled (reset) loop temperature
• Optional Auxiliary Out (low voltage) closure on DHW call -
Simplified wiring when used with a modulating/condensing
boiler
• Optional Auxiliary Pump (line voltage) closure on DHW call -
More convenient when using a valve on a DHW loop