Honeywell Prestige 2.0 THX9421 Manual page 116

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THX9321 PRESTIGE 2.0 AND THX9421 PRESTIGE
5. If ASHRAE was selected for ISU 10050, select the
Number of Bedrooms and Size of House. See Fig.
257.
Fig. 257.
6. If ASHRAE was selected for ISU 10050, enter the
Equipment Ventilation Rate (CFM). Be sure this set-
ting corresponds with the actual ventilator speed.
This setting determines how often the ventilation
equipment will operate to meet the ASHRAE 62.2
Standard. The thermostat will indicate the following
based on the Equipment Ventilation Rate, Square
Footage and Number of Bedrooms. See Fig. 258.
• Provides an indication if it meets or does not meet
the ASHRAE 62.2 Standard.
• Provides% run time that is needed to meet the
ASHRAE 62.2 Standard.
Fig. 258.
68-0311—07
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IAQ WITH EIM
7. Select a Ventilation Priority (see Fig. 259):
c. Lockouts are Priority: The thermostat places a
priority on lockouts versus the ASHRAE 62.2 ven-
tilation standard. The thermostat will not run
ventilation during the following lockout condi-
tions (if configured) unless you manually call for
ventilation:
(1) Lockout Ventilation during Outdoor Condi-
tions (ISU 10130)
(2) Lockout Ventilation on Humidification or
Dehumidification Calls (ISU 10140)
(3) Lockout Ventilation during "Sleep" (Residen-
tial) or "Unoccupied" (Commercial) program
periods. Note: This option is set by the user on
the Ventilation screen in the Menu.
d. ASHRAE is Priority: ASHRAE requires additional
ventilation following a long off cycle. The ther-
mostat meets the ASHRAE 62.2 ventilation stan-
dard by running additional ventilation when
outdoor conditions are favorable. If ASHRAE
cannot be met when outdoor conditions are
favorable, the thermostat will override the out-
door lockouts and run ventilation. When using
this option, it is recommended to increase the
rate (CFM) of the ventilation equipment to meet
the ASHRAE 62.2 ventilation standard in a
shorter run time.
NOTE: ISU 10140 "Lockout Ventilation on Humidi-
116
fication or Dehumidification Calls" is not an
option when you select "ASHRAE is Priority".
The ability to lockout ventilation during the
"Sleep" or "Unoccupied" program periods is
not an option when you select "ASHRAE is
Priority".
Fig. 259.