Honeywell LCBS Applications Manual page 11

NOTICE
Some economizer strategies are not applicable for all climates in the United States. ASHRAE Standard 90.1 - 2010
Table 6.5.1.1.3 A describes what economizer strategies should be used in various climate regions in the United
States. For example, the fixed enthalpy economizer strategy is not permitted in U.S. climate zones 1b, 2b, 3b, 3c,
4b, 4c, 5b, 5c, 6b, 7, and 8 and fixed dry bulb and differential dry bulb economizer strategy is not permitted in U.S.
climate zones 1a, 2a, 3a, and 4a.
Honeywell Integrated Economizer Control, Climate Zones, Getting
Tactical!
If outdoor air is cool enough, our integrated economizer system begins to control our outdoor air actuator to attempts to
control to mixed air set point. The control is mitigated by a throttling range set point.
WARNING
Unless you are instructed to do so by your Honeywell or LCBS Connect control system distributor, you should
NEVER have to change mixed air set point and throttling range. Over 8M of the control systems we've
provided to the HVAC industry have these set points "hard coded" in the devices with literally no complaints,
callbacks, or service interventions.
Pacific Northwest National Laboratory & Oak Ridge National Laboratory August 2010
http://www1.eere.energy.gov/buildings/publications/pdfs/building_america/ba_climateguide_7_1.pdf
ASHRAE 90.1 PERMISSABLE ECONOMIZER CONTROL TYPES, HIGH LIMIT, CHAGEOVER OPTIONS
CONTROL TYPE
FIXED DRY BULB TEMP
DIFFERENTIAL DRY BULB TEMP
FIXED ENTHALPY WITH FIXED DRY
BULB TEMP
DIFFERENTIAL ENTHALPY WITH
FIXED DRY
When the mixed air control system has captured all the cooling value from outdoor air it can, the system will begin to
augment that call for cooling with mechanical cooling. An integrated low limit is also offered.
Fig. 3.
Table 2.
ALLOWED IN CLIMATE ZONES
1B, 2B,3B,3C,4B,4C,5B,5C,6B,7,8
5A, 6A
1A,2A,3A,4A
1B, 2B, 3B, 3C, 4B, 4C, 5B,5C,6B,7,8
ALL
ALL
11
LCBS CONNECT SOLUTION
HIGH LIMIT, CHANGEOVER SETPOINT
OUTDOOR AIR TEMP > 75°F
OUTDOOR AIR TEMP > 70°F
OUTDOOR AIR TEMP > 65°F
OUTDOOR AIR TEMP > RETURN AIR
TEMP
OUTDOOR AIR ENTHALPY > 28
BTU/LB OR OUTDOOR AIR TEMP >
75°F
OUTDOOR AIR ENTHALPY > RETURN
AIR ENTHALPY OR OUTDOOR AIR
TEMP > 75°F
31-00118EFS—01