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Table 6. Smart Hub Parameters
Parameter
(In alphabetical
order)
Description
Ventilation
High Outdoor
Temperature Limit
Parameter range is 60 to 115ºF. Default is 100ºF. Can be adjusted in increments of 5ºF.
While the outdoor temperature is equal to or higher than the setting for
Ventilation High Outdoor Temperature Limit
, ventilation does not run. When locked out due
to high outdoor temperature, it will become unlocked when either the outdoor temperature is missing, or when the temperature reported is 1°F less than the
Ventilation
High Outdoor Temperature Limit
setting when display units are in Fahrenheit, or is reported as 0.5°C less than lock out setting when the display units are Celsius.
Ventilation
Low Outdoor
Temperature Limit
Parameter range is -20 to 55ºF. Default is 0ºF. Can be adjusted in increments of 5ºF.
While the outdoor temperature is lower than the setting for the
Ventilation Low Outdoor Temperature Limit
, ventilation does not run. When locked out due to low
outdoor temperature, it will become unlocked when the outdoor temperature is missing, or when the temperature reported is 1°F higher than the
Ventilation Low
Outdoor Temperature Limit
setting when display units are Fahrenheit, or is reported as 0.5°C higher than lock out setting when the display units are Celsius
Ventilation High
Outdoor Dew Point
Limit
Parameter range is 45 to 80ºF. Default is 55ºF. Can be adjusted in increments of 5ºF.
While the outdoor dew point is higher than the setting for the high outdoor dew point limit, ventilation does not run. When locked out due to high outdoor dew point limit,
it will become unlocked when the outdoor dew point is missing, or when the dew point temperature reported is 1°F less than the lock out setting when display units are
Fahrenheit, or is reported as 0.5°C less than lock out setting when the display units are Celsius.
Ventilation Control Mode - ASHRAE
•
In this mode the thermostat can assist the installer by validating the ventilation CFMs are capable of meeting the ASHRAE required ventilation volumes, but the thermostat has no ability to control
CFM from the HRV/ERV.
•
The system first tries to satisfy the ventilation volume by only ventilating while conditioning is occurring. Continuous fan is not considered conditioning.
•
The total volume of ventilation air is accumulated and stored to compare against the target hourly ventilation volume (Vhr). The accumulated value resets each hour.
•
When the remaining required volume of ventilation air for the hour divided by the fan only ventilation rate is equal to or greater than the time remaining to ventilate for the hour and no conditioning
is occurring, the system begins ventilation using continuous fan and does not stop until the target hourly ventilation volume requirement is satisfied.
•
When ventilating without a conditioning demand, the ventilation output is active as well a continuous indoor fan demand.
•
When ventilating with a conditioning demand, the ventilation output is active with the conditioning demand outputs.
•
When the system is ventilating, the user interface can indicate as such by showing “ventilating” to the user on the home screen.
Ventilation Rates
Thermostat ventilation CFM parameters are to be adjusted only after the HRV/ERV set up is completed and the CFMs are known. Once the thermostat’s CFMs are adjusted they are
used with the thermostat’s timer algorithm to determine how long to run the HRV/ERV and to change from low to high speed if a 2-stage HRV/ERVs.
Ventilation Rate
(Only listed for
1-speed ERV or HRV
Parameter range is 20 - 500 CFM. Default is 130 CFM. Can be adjusted in increments of 1.0 CFM.
Ventilation Rate for
Low Speed
(Only listed for
2-speed ERV or HR
Parameter range is 10 - 200 CFM. Default is 50 CFM. Can be adjusted in increments of 1.0 CFM.
Ventilation Rate for
High Speed
(Only listed for
2-speed ERV or HRV
Parameter range is 20 - 500 CFM. Default is 130 CFM. Can be adjusted in increments of 1.0 CFM.
Ventilation Outdoor
Condition Override
Options are Disabled (default) or Enabled.
ASHRAE
Compliance Check
= NO (Ventilation CFM too low to comply with ASHRAE 62.2) or = YES (Current settings comply with ASHRAE 62.2)
