Honeywell AQ25A Series Technical Reference Booklet page 107

AQ252 Universal Injection/Mixing Boiler
Reset Control Panels
PRODUCT DESCRIPTION
The AQ252 family of AQUATROL® Universal Injection/Mixing
Boiler Reset Controls provides simplified, energy-efficient
outdoor temperature compensated control of a high-
temperature boiler loop and a lower temperature mixed loop in
residential hydronic heating systems. The AQ252 easily
converts a single-zone heating system into a room-by-room
comfort control system, or upgrades a basic, relay-logic
zoning system to intelligent Zone of Greatest Demand control,
with outdoor reset for increased energy efficiency with
reduced boiler cycling. The boiler controls of the AQ252 can
ensure ample supply of hot water for both space heating and
priority generation of domestic hot water for bathing, dishes
and laundry.
FEATURES
The AQ252 family have the following features:
• Controls one boiler loop and one mixed temperature
loop.
• Outdoor temperature compensation (reset), or Load
reset based on indoor temperature feedback, or none.
• Zone synchronization through Zone of Greatest
Demand control.
• Domestic hot water (DHW) priority and priority
override protection.
• Customizable control settings and schedules allow for
greater level of control and comfort.
• Use of variable speed injection pump or motorized
mixing valve for mixed temperature loop control.
• Central set-back schedules available.
• Zoning Control for up to four, single-stage or two, two-
stage zones as shipped; can be expanded to a total of
16 zones with AQ255 or AQ257 expansion zoning
panels, and up to 64 zones by using up to three AQ254
Add-a-Temperature expansion panels and additional
expansion zoning modules.
IMPORTANT
To ensure correct installation and proper operation of
the control, perform the 7 installation steps in the
order numbered in the "Contents" below.
Specifications ...................................................................
1 Installation Preparation ..................................................
2 Mounting ........................................................................
3 Wiring Procedure ...........................................................
4 Program and Configure the Control Panel .................... 15
5 Test and Check Out the Installation ............................... 19
6 Purge Air from all System and Zone Piping .................. 20
7 Document and Keep a record of all System Settings .... 20
Troubleshooting ................................................................ 21
Appendix .......................................................................... 24
User Menu .............................................................. 24
Installer Menu ......................................................... 31
PRODUCT DATA
Contents
2
3
5
7
69-1986-02