Honeywell AQ25A Series Technical Reference Booklet page 292

Expansion Zoning Panels
Model Number Application
AQ2541E0 Extends the capacity of an AQ2000 network by
up to 16 additional zones AND one extra loop
temperature
AQ2554V2 4 zones of zone valves without end switches
AQ2574V4 4 zones of zone valves with end switches
AQ2554P2X 4 zones of pumps
AQ2558P2X 8 zones of pumps
8
AQ255 and AQ257 Expansion Panels
Zoning Expansion Panel Features:
• Controls up to either 4 or 8 zones depending on the model
• Zone synchronization
• Auto test function to check out zones at system start-up
• R-C transformer and B-B data bus terminal connections and
network communication for easy expansion
• Status LEDs for easy diagnostics
• Use with 2-wire "polarity insensitive" communicating thermostats
• Expansion panels add-on simply and require only six field-installed
wires to connect to the system
• Integral low and line voltage wire conduit within panel enclosure
allows you to connect multiple panels together without the need
for running wire outside panels to connect them
AQ254 Add-A-Temperature Injection/
Mixing Expansion Panels
Even with 64 zones, all zones can still be diagnosed, checked out,
and settings adjusted from the main panel without ever having to
be in front of the thermostat itself!
The convenient channel connectors allow you to easily add a zone
without running wires outside of the panels. This eliminates the risk
of having wires exposed to the homeowner outside of the panel,
and makes for a clean and organized installation.
To connect the panels, remove the wire channel plugs, reverse
them and re-insert them.