Johnson Controls 100 Series User Manual

JOHNSON CONTROLS
98
FORM 100.50-NOM12
ISSUE DATE: 04/02/2019
SECTION 5 – SEQUENCE OF OPERATION
Supply Air Tempering
• This sequence uses the unit heating source to tem-
per the supply air during the winter months when
a large volume of outside air is required for ven-
tilation.
• It is only applicable on VAV and FlexSys cong-
ured units.
• SZVAV units utilize the comfort ventilation se-
quence. Refer to Comfort Ventilation on page
102 for a description of this sequence.
• Supply air tempering works best with either mod-
ulating gas or hot water/steam since the heat out-
put can be modulated down to a bare minimum.
Supply Air Tempering Setup
• The Series 100 unit must have a heating source
installed.
• The heating source must be User Enabled.
• Supply air tempering must be User Enabled in the
PROGRAM-COOLING menu.
Supply Air Tempering Sequence of Operation
• The supply air tempering sequence is slightly dif-
ferent depending on the heating source. The fol-
lowing sections detail the different sequences.
Modulating Gas and Hot Water/Steam Heat
• The IPU board monitors the current SAT.
• Supply air tempering becomes ACTIVE
when the current SAT (mixed SAT for Flex-
Sys) becomes 2.5°F colder than the active
cooling SAT setpoint (mixed SAT setpoint
for FlexSys) for 5 minutes.
• The heating source is turned ON when both
conditions below are satisfied:
• The economizer output is less than 5%
• There has been no compressor opera-
tion for 10 minutes
• The heating source is controlled to the active
cooling SAT setpoint (mixed SAT setpoint
for FlexSys).
• Supply air tempering becomes INACTIVE
when the following conditions are satisfied:
1. Modulating Gas Heat
• The current SAT (mixed SAT for
FlexSys) becomes 4.0°F warmer
than the active cooling SAT setpoint
(mixed SAT setpoint for FlexSys)
for 4 minutes.
• Modulating gas heat is at min low
fire
2. Hot Water/Steam Heat
• The current SAT (mixed SAT for
FlexSys) becomes 4.0°F warmer
than the active cooling SAT setpoint
(mixed SAT setpoint for FlexSys)
for 4 minutes.
• The hot water/steam valve position is
less than 2%
Staged Gas and Electric Heat
• The IPU board monitors the current SAT.
• Supply air tempering becomes ACTIVE
when both conditions below are satisfied:
1. The current SAT (mixed SAT for Flex-
Sys) becomes 2.5°F colder than the ac-
tive cooling SAT setpoint (mixed SAT
setpoint for FlexSys) for 5 minutes.
2. The current heat entering temperature is
less than the active cooling SAT setpoint
(mixed SAT setpoint for FlexSys) for 5
minutes.
• The heating source is turned ON when both
conditions below are satisfied:
1. The economizer output is less than 5%
2. There has been no compressor opera-
tion for 10 minutes
• The heating source is controlled to the active
cooling SAT setpoint (mixed SAT setpoint
for FlexSys).
• Supply air tempering becomes INACTIVE
when the current heat entering temperature
becomes greater than the active cooling SAT
setpoint for 5 minutes.

Johnson Controls 100 Series Specifications

General

Brand	Johnson Controls
Model	100 Series
Category	Air Conditioner
Language	English