Our site works best with Javascript enabled.
New Website Design Coming Soon
Take a Look

Need Help? Call
MON-FRI 8:30am-5:00pm Central
Product Image
Honeywell AQ25542B/U
4 Zone Expansion Panel for Pumps or Zone Valves WITHOUT End Switches

Your Price:
Compare to:$148.99
You save:$36.00
See Shipping Cost

The AQ255 and AQ257 family of AQUATROL Expansion Zoning panels work with AQ2000 Boiler Control Panels and AQ1000 Communicating Thermostat to control up to 4 space heating zones (or 8, for the AQ25542B/U Panel). Can be combined with additional expansion zoning panels and an AQ2000 control panel for a total of 16 space heating zones.


  • AQ255 for zoning with pumps or zone valves without end switches.
  • Use with 2-wire polarity insensitive communicating thermostats.
  • Allows zone synchronization through Zone of Greatest Demand control.
  • Auto test function to test zones at system start up. It allows for operator controlled testing of zones; includes pause/restart capability.
  • LED lights for easy diagnostic of zone operation.
  • Allows zoning with either "Normally Open" or "Normally Closed" zone valves.
  • Adjacent zoning panels can operate different zone equipment - one panel may control 4 pumps while another may control 4 zone valves.
  • Easily switch from zone valves to pumps with same zoning module - just flip one DIP switch. Ensure correct voltage is applied (120 Vac for pumps, 24 Vac for valves)
  • R-C transformer and B-B data bus terminal connections and network communication for easy expansion.
  • Zones can be set to energize a parallel group pump.
  • Line or low-voltage output for zoning equipment (pumps or valves) 38 VA Transformer with self resetting electronic fuse.

Your Order
Ways to Order
See Order Status
Modify or Cancel Order
Missing Order Item
Damaged Shipments
Warranty Claims
View Quotes
Request Custom Equipment
Technical Support
Learning Center
Instruction Manuals
Contact Technical Support
Shipping Policy
Return Policy
Scratch-N-Dent Policy
Volume Discount Policy
Privacy Policy
Website Terms of Use
About Us
Customer Reviews
(800) 865-5931
Monday to Friday
8:30am - 5:00pm Central
  Mailing Address
1901 N. Clybourn Avenue
Suite 200
Chicago, IL 60614
[email protected]
or Contact Us Here
(425) 928-2455
© Copyright 2002-2014, Alpine Home Air Products. All Rights Reserved. A Todd Arthurs Company, Inc