Daikin MicroTech II Operation And Maintenance Manual

Also see for MicroTech II: Installation and Maintenance Installation and maintenance manual Installation and maintenance manual

Daikin MicroTech II Operation And Maintenance Manual Manual pdf 33 page image

www.DaikinApplied.com 33 OM 752-4desCrIptIon of operatIonTemperature Comparison with Enthalpy Comparison Economizer (optional)If the optional Leading Edge economizer function is selected, the unit ventilator isprovided from the factory with both the IA humidity and OA humidity sensors, whichare used along with the IA temperature and OA temperature sensors to calculate IAenthalpy and OA enthalpy. In this case, the UVC is factory set for the Leading EdgeEconomizer Strategy and uses the Temperature Comparison with Enthalpy Compari-son Economizer function.Note: Temperature Comparison with Enthalpy Comparison requires both an optional OAhumidity sensor and an optional IA humidity sensor.Table 18: Economizer enable/disable tests definedTests Economizer enable/disable tests Enable test Disable testA OA temp set point Effective OA Temp < (Econ OA Temp Setpt – Econ Temp Diff) Effective OA Temp >= Econ OA Temp SetptB IA/OA differential temp Effective OA Temp < (Effective Space Temp – 3.6°F – EconTempDiff) Effective OA Temp >= (Effective Space Temp – 3.6°F)C OA enthalpy set point Effective OA Enthalpy < (Econ OA Enthalpy Setpt – Econ Enthalpy Diff) Effective OA Enthalpy >= Econ OA Enthalpy SetptD IA/OA differentialenthalpy Effective OA Enthalpy < (Effective Space Enthalpy – Econ Enthalpy Diff) Effective OA Enthalpy >= Effective Space EnthalpyTable 19: How economizer enable/disable tests are selectedEconomizerstrategy Space temp sensor OA temp sensor Space humidity sensor OA humidity sensor Economizer enable/disable testsAll Unreliable Ignored Ignored Ignored OA damper closedIgnored Unreliable Ignored Ignored OA damper closedBasic Reliable Reliable Ignored Unreliable Test BReliable Reliable Ignored Reliable Test CExpanded Reliable Reliable Ignored Reliable Test C and Either Test Bor Test ALeading EdgeReliable Reliable Reliable Reliable Test D and Test BReliable Reliable Reliable Unreliable Test BReliable Reliable Unreliable Unreliable Test BReliable Reliable Unreliable Unreliable Test BNote: The hard-wired sensor and the equivalent input must both be unreliable for the value to be considered unreliable.Networked Space Humidity Sensor CapabilityA networked space humidity sensor can be network interfaced with the Space HumidityInput variable. When the Space Humidity Input variable is used (valid value), it auto-matically overrides the hard-wired space humidity sensor (if present).Networked Outdoor Humidity Sensor CapabilityA networked outdoor humidity sensor can be network interfaced with the Outdoor Hu-midity Input variable. When the Outdoor Humidity Input variable is used (valid value), itautomatically overrides the hard-wired outdoor humidity sensor (if present).CO2 Demand Controlled Ventilation (optional)Ventilation equipment typically uses fixed damper positions to determine the amountof OA for proper ventilation within the space. Most commonly, the fixed position of theOA damper is based on the maximum number of occupants the space is designed toaccommodate. However, this fixed OA damper operation ignores the fact that mostspaces during the day have varying occupancy levels and may only rarely reachmaximum design occupancy levels. This type of fixed damper control for ventilation isenergy wasteful since you are treating OA not actually needed for ventilation during lowoccupancy levels.People produce CO2 when they breath; the CO2 level within the space has a directrelationship with the number of people within that space.