Lennox iHarmony 10C16 User Manual

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in this range but is highly sensitive to air lter loading
restriction.
» Select Zoning Control.
- Verify the appropriate zone damper is 100% open and all others
are closed.
- Verify from discharge air temperature using the following proce-
dures:
◊ On modulating units, the value will remain very constant be-
tween zones due to the gas valve modulating proportionally with
the airow.
◊ On staged units the CFM will determine the DATS value based
on a xed BTU output.
> Excessive air per zone will drive the DAT below target air
setting and initiate 2nd stage
> 2nd stage will then drive the temperature up to the over-
shoot limit and drop out with minimum air.
> The cycle is repeated with minimum 20° uctuating dis-
charge temperature.
> Adjust each zone to operate in the adequate air range of the
zoning map within the proper IDBP percentage.
> The position of the DATS should not be changed as it is set
for continuous maximum capacity operation within the ade-
quate air range of the zoning map.
+ Verify DATS is tracking slow and steady in .4 - .5 incre-
ments. Temperature reading in large increment indicate
the CFM may need to be adjusted and IDBP % checked.
+ Verify steady state DATS in diagnostics is approximate-
ly the same as DAT operating target as per zoning map.
Pocket formula may be needed for this value.
+ if minimum air CFM was selected to specically accom-
modate duct sizes >79% IDBP the DAT will run higher
as per the zoning map temperature ranges.
+ Verify DAT operating temp is less than zoning heating
limit or cool down mode will initiate, and short cycling
will occur.
» Repeat for each zone installed
- Select the next larger zone.
- Initiate 5° heating call on subsequent zone while previous zone is
still on.
- Wait for the “heating” status symbol to be displayed.
- Scroll to previous zone and terminate call.
◊ This will prevent unit from cycling off.
◊ Proceed to diagnostics and record results.
» If CFM changes need to be made do not use the test mode. Return to
dealer control center > equipment > reset > recongure system> stop on
the 6th commissioning screen.
- Adjust CFM per zone as needed.
- Changes will be saved and stored.
• Cooling test per zone
» Same sequence as heating.
» DATS position will not be changed.
» DATS calibration is sensitive to specic heating performance.
» DATS calibration in cooling mode.
- Adjust CFM to respond to target air cooling temp setting selected in
zoning setup
- Adequate air on the zoning map will nd a thermal balance point
between target and 7° above that temp.
- If the CFM selected achieves a point inside that range the ODU will
not continue to modulate up (staged or modulating units).
- If the thermal balance point is not close enough to the target air
temp selected the CFM can be lowered to achieve that design
condition.
» Good practice recommends a balance point within 2°F of target to ac-
commodate for air lter loading restriction
» Discharge air temperature is subject to uctuate based on differences in
total heat load.
» Return to home screen and set all zones to normal operations.
Lennox Communicating Indoor Control Link Settings
When using the iHarmony
®
zoning system with a Lennox communicating In-
door unit and non-communicating (24VAC) outdoor unit all applicable control
links illustrated in “Figure 7. Damper Control Jumpers LEDs and Connec-
tions” on page 14 should be congured as indicated. Failure to cut or not
cut only the required links will result in the system being inoperable.
Table 9. Damper Control Connections, Insertion Bridge
and Jumpers
Damper Control Label Description
INDOOR (Connection to iComfort furnace or air handler)
C RSBus 24VAC common

Lennox iHarmony 10C16 Specifications

General

Brand	Lennox
Model	iHarmony 10C16
Category	Control Unit
Language	English