Honeywell AQ255, AQ257 Catalog Page

AQUATROL Zoning System

AQ255 and AQ257 Zoning Expansion Panel for Hydronic Zoning
System

The AQ255 and AQ257 family of AQUATROL Expansion Zoning
panels work with AQ2000 Boiler Control Panels and AQ1000
Communicating Thermostats to control up to 4 space heating
zones (or 8, for the AQ25582B Panel). Can be combined with
additional expansion zoning panels and an AQ2000 control panel
for a total of 16 space heating zones.

• AQ257 for zoning with zone valves with end switches

• 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 visual 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 to all zone
equipment on a panel (120 Vac for pumps, 24 Vac for valves)

• R-C transformer and B-B data bus terminal connections (network
communication) for easy expansion.

• Zones can be set to energize a group pump via Aux Out dry contacts
on main control panel (AQ250, AQ25A, AQ251, AQ252) or
expansion control panel (AQ254).

• Zone synchronization through Zone of Greatest Demand control.

• 38 VA Transformer with self resetting electronic fuse.

Application: Zoning control for hydronic zoning system
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)

User Interface (Setting, Programming): (DIP Switches)
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

Zone Module Thermostat input: Low voltage, Class II, 2-wire polarity-

insensitive, digital communicating with power link to AQ1000 series
thermostat.

Zone Output Contact Rating: 120 Vac/250 Vac, 5A, 1/3 HP
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)

Operating Humidity Range (% RH): 5 to 90% RH, non-condensing
Approvals

Canadian Standards Association: CSA C/US Certified to CSA and

UL Standards, File No. LR76030

Product Number

* AQ25542B/U Zone pumps or 2-wire valves (line

* AQ25582B/U Zone pumps or 2-wire valves (line

* AQ25742B/U 2-wire valve (24 Vac) 4 3.9 bs 1.8 kg AQ10X38 24 Vac 38 VA transformerAQ15540B 4-zone

* AQ25744B/U Zone valves with end switches (24

* TRADELINE models • SUPER TRADELINE models

Type of Zoning Devices
Controlled

voltage)

voltage)

Vac )

Number of
Zones
Controlled

4 2.1 bs 1 kg AQ15540B 4-zone pump expansion module

8 2.6 bs 1.3 kg AQ15540B 4-zone pump expansion module

4 3.9 bs 1.8 kg AQ15740B 4-zone valve with end switch expansion

Weight

Replacement Partslb kg

pump expansion module

moduleAQ10X38 24 Vac 38 VA transformer

190 customer.honeywell.com 70-6910