JOHNSON CONTROLS
59
FORM 100.50-NOM12
ISSUE DATE: 04/02/2019
5
SECTION 5 – SEQUENCE OF OPERATION
The Series 100 unit is a sophisticated machine that is
capable of performing many different functions. It can
operate as three different unit types. It has many unit
options with different sequences for each option.
Every Series 100 unit has tandem compressors installed
for mechanical cooling and a supply fan with a variable
frequency drive (VFD). There is also a control panel in-
stalled with an IPU control board that contains the soft-
ware necessary for unit operation. All other components
are optional and are selected during the ordering process.
Locate the Unit Options tag (
) affixed to the unit
to see what type of options were installed on the unit at the
factory. Each of these different options and sequences are
described in greater detail in this section.
LD28114
FIGURE 25 -
UNIT OPTIONS
To see a complete list of the OPTIONS,
PROGRAMS, and SETPOINTS menus,
as well as min/max values and factory
defaults, refer to
Please refer to
for a list of acronyms and abbreviations
UNIT TYPE
The Series 100 unit can operate as three different
unit types. The unit type can be viewed and selected
through the OPTIONS-UNIT DATA menu in the User
Interface (UI).
These three unit types are selected in the ordering
process of the unit and should not need to be changed
in the field. Each of the unit types have different pro-
gramming and sequences of operation. These different
sequences are described in further detail throughout
this section.
Variable Air Volume (VAV)
• A VAV unit type is an HVAC system that has VAV
boxes installed in the ductwork. Typical VAV sys-
tems have overhead ductwork that provides con-
ditioned air down to the space.
• A VAV unit has a supply fan controlled by a VFD
that is capable of running at different speeds to
maintain a constant duct static pressure.
• The VFD speed is controlled by a duct static pres-
sure transducer that also provides high duct static
pressure protection.
Single Zone VAV (SZVAV)
• A SZVAV unit type is an HVAC system that has
no VAV boxes installed in the duct work. SZVAV
systems are replacing Constant Volume (CV) sys-
tems per ASHRAE 90.1-2010.
•
A SZVAV configured unit has a supply fan, con
-
trolled by a VFD that is capable of running at dif-
ferent speeds according to a cooling/heating de-
mand or supply fan only demand.