13
JOHNSON CONTROLS
FORM 145.05-SU2 (1207)
WATER SIDE ECONOMIZER
The feature allows the unit to use a water side economizer
instead of or in conjunction with the compressors to
maintain the conditioned space conditions.
Field Wiring
None required.
Programming
The following items must be programmed through the
“
Setpoints
” section of the User Interface:
•
“H2O Econ En”
– This parameter must be set to
ON. The default value is OFF
•
“Econ-S/A Tmp En”
- This parameter must be set
to ON if you want the water side economizer to
be controlled by a supply air temperature. The
default value is OFF.
•
“Econ-R/A Tmp En”
- This parameter must be set
to ON if you want the water side economizer to
be controlled by a return air temperature. The
default value is OFF
•
“Econ Valve Min”
– This parameter establishes
the minimum position of the water side econo-
mizer valve. The parameter can be set between
0 and 100%. The default value is 0%.
CONDENSER WATER BYPASS
The unit can be ordered with a water side economizer
valve, a condenser water by-pass valve, or none of
the above. If the unit is ordered with a condenser
water by-pass valve, the valve will operate inversely
to the operation of the condenser water valve. As
the condenser water valve opens to increase the flow
through the condenser, the water by-pass valve will
close to decrease the amount of by-pass.
Field Wiring
None required.
Programming
The following item must be programmed through the
“Setpoints”
section of the User Interface:
“BYPASS VALVE MAX”
– This is the maximum
position of the condenser water by-pass valve.
The default value is 50%.
