Johnson Controls LSWU User Manual

JOHNSON CONTROLS
142
FORM 145.05-NOM7
ISSUE DATE: 10/31/2019
SECTION 5 – SEQUENCE OF OPERATION
The unit display shows the Heating Sys-
tem Status as Inactive while in Active Slab
Control. The Supply System Status shows
as Active.
Unoccupied to Occupied
The Unit Controller checks the Underfloor Slab Temp
immediately after switching from UNOCCUPIED to
OCCUPIED STANDBY (if the Unit Controller calls
from OCCUPIED COOLING W/ OR W/O BYPASS
during this time, Active Slab Control is terminated).
If Underfloor Slab Temp ≤ the MX SAT SP minus
2.0°F, the Underfloor Temp Override becomes Active.
• Underoor Temp Control is set to MX SAT SP
plus 10.0°F
• The Unit Controller generates a call for heat
a. If staged heat (staged gas or electric), Unit
Controller starts the first stage of heat
b. If modulating (modulating gas or hot water/
steam), the Unit Controller controls the SAT
to the UNDERFLOOR TEMP CONTROL
SP
• Heating operation continues until:
a. The Underfloor Slab Temp ≥ the MX SAT SP
OR
b. 20 minutes time has elapsed
Occupied to Unoccupied
The Unit Controller checks the Underfloor Slab Temp
immediately after switching from an OCCUPIED
mode to UNOCCUPIED STANDBY.
If the Underfloor Slab Temp > the RAT minus 2.0°F,
Underfloor Temp Override becomes Active.
• The Underoor Temp Control SP is set to the RAT
SP plus 10.0°F
• The Unit Controller generates a call for heat
a. If staged heat (staged gas or electric), the
Unit Controller starts the first stage of heat
b. If modulating (modulating gas or hot water/
steam), the Unit Controller controls the SAT
to the UNDERFLOOR TEMP CONTROL
SP
• Heating operation continues until:
a. The Underfloor Slab Temp > RAT plus
1.0°F
OR
b. 20 minutes time has elapsed
FlexSys: All Other Sequences
The other sequences of operation for a FlexSys unit
follow the same procedures as a VAV configured unit.
TABLE 26 - SUPPLY AIR DENSITY FROM TEMPERATURE AND ALTITUDE
UNIT
INSTALLED
ALTITUDE
SUPPLY AIR TEMP CURRENT
40 50 60 70 80 90 100 110
0 0.0787788 0.0769444 0.0751429 0.0736991 0.0722022 0.0708069 0.0695253 0.0684611
1000 0.0759635 0.0741844 0.0724350 0.0710365 0.0695842 0.0682308 0.0669888 0.0659610
2000 0.0732022 0.0714773 0.0697790 0.0684250 0.0670164 0.0657042 0.0645010 0.0635089
3000 0.0705491 0.0688762 0.0672270 0.0659157 0.0645491 0.0632765 0.0621106 0.0611528
4000 0.0678959 0.0662751 0.0646750 0.0634064 0.0620818 0.0608488 0.0597202 0.0587966
5000 0.0654535 0.0638806 0.0623257 0.0610964 0.0598105 0.0586139 0.0575196 0.0566276
6000 0.0630110 0.0614860 0.0599764 0.0587864 0.0575392 0.0563790 0.0553190 0.0544586
7000 0.0606497 0.0591710 0.0577051 0.0565531 0.0553432 0.0542183 0.0531915 0.0523616

Johnson Controls LSWU Specifications

General

Brand	Johnson Controls
Model	LSWU
Category	Chiller
Language	English