Lennox 16B27 Installation Instructions

Page 7
Conguring Unit
This section identies the requirements for conguring the air handler unit for unit size, heat mode selection, EVENHEAT
operation and Heat Pump/Cooling Operations.
Air Handler
Control Checkout
Power-up- Unit Size Code (Number or letter) displayed
represents unit size code (air handler model size and capacity).
If three horizontal bars displays, Air Handler Control (AHC)
does not recognize unit size code (air handler model size and
capacity).
AHC
recognizes
Unit Size
Code?
Electric
heat
Installed?
Finished
Which Heat
Mode?
Refer to EVENHEAT operation flow diagram, air handler or
ECB38 Electric Heat installation instructions.
W1 Call?
Ye sNo
Ye s
Standard
EVENHEAT
Refer to Heat Pump or Cooling
Sequence of Operation flow
diagrams, Air Handler or ECB38
Electric Heat installation
instructions.
A call for electric heating first, second or third stage is
initiated when 24 VAC (R) is detected on W1, W2 and
W3 inputs on AHC. (Factory mounted metal jumpers
connect W1 to W2 and W2 to W3.)
At the completion of each heat section demand (W1,
W2, and W3), the control board will immediately
de-energize the corresponding pilot relay(s).
At the completion of all heating demands, the indoor
blower will run for an additional 10 seconds before
de-energizing.
No
Ye s
NOTE - If the call for lower heat section is removed,
AHC will automatically de-energize higher heat
sections.
Indoor blower will immediately start to deliver CFM as
set by heating mode jumper on board with activation of
first electric heat pilot relay.
22 VDC pilot relays on board are energized one at a
time. There is a minimum of 10 seconds delay between
pilot relay activations.
After all electric heat installations, AHC must be
manually configured to detect number of heat sections.
Refer to Configuring/Detecting electric heat sections
flow diagram, Air Handler or ECB38 Electric Heat
installation
IMPORTANT: Field replacement controls
may need to be manually configured to
validate air handler unit size code.
Refer to Configuring Unit Size Codes flow
diagram, Air Handler or ECB38 Electric Heat
installation instructions.
ONE (H1)
H1
TWO (H1-H2)
H1
H2
H2
THREE
(H1-H3)
H1
H2
H3
FOUR (H1-H4)
H1 AND H2
H3
H4
FIVE (H1-H5)
H1 AND H2
H3 AND H4
H5
T-STAT CALL
W1
W2
W3
NUMBER OF HEAT SECTIONS DETECTED
NOTE - AHC will not recognize higher heat section
demand if lower heat demand is not present.
AIR HANDLER CONTROL (AHC)
PUSH
BUTTON
No (Display
Alarm Code 302)
SINGLE
CHARACTER
DISPLAY
FIGURE 10. Air Handler Control Checkout

Lennox 16B27 Specifications

General

Brand	Lennox
Model	16B27
Category	Heat Pump
Language	English