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DocuSign Envelope ID: 9826C043- 4C32- 49CD- A4CC- DC28ABAB7CE7 <br />SECTION 239500 - MULTI - INDOOR VRV SYSTEM <br />• Configurable Setup (Cooling) and Setback (Heating) setpoints <br />when unit is Off (unoccupied) <br />iii) Time setting in 1- minute increments <br />iv) Timer Extension shall be used for a timed override (settable from 30 <br />— 180 minutes) to allow indoor unit operation during the unoccupied <br />period <br />7) A maximum of 40 exception days can be schedule on the yearly sched- <br />ule (repeats yearly) <br />i) Exception days shall be used to override specified days on the weekly <br />schedule based upon irregular occupied /unoccupied conditions <br />ii) Exception days can be configured on a set date (Jan 1) or floating <br />date (1st Monday in September) <br />Controller shall support auto - changeover. <br />1) Auto - change shall provide Fixed (default), Individual, Averaging, and <br />Vote changeover methods for both Heat Pump and Heat Recovery sys- <br />tems based upon the changeover group configuration. This will allow for <br />the optimal room temperature to be maintained by automatically switch- <br />ing the indoor unit's mode between Cool and Heat in accordance with <br />the room temperature and setpoint. The following changeover scheme <br />shall be applicable to the Fixed, Individual, and Averaging methods. <br />i)Changeover to cooling mode shall occur at cooling setpoint + 1 °F <br />(0.5 °C) as the primary changeover deadband and takes the guard <br />timer into consideration <br />• Configurable from 1 — 4 °F (0.5 — 2 °C) <br />ii) Changeover to cooling mode shall occur at the primary changeover <br />deadband to cooling + 1 °F (0.5 °C) as the secondary changeover <br />deadband. <br />• Configurable from 1 — 4 °F (0.5 — 2 °C) <br />iii) Changeover to heating mode shall occur at heating setpoint - 1 °F <br />(0.5 °C) as the primary changeover deadband and takes the guard <br />timer into consideration <br />• Configurable from 1 — 4 (1F (0.5 — 2 °C) <br />iv) Changeover to heating mode shall occur at the primary changeover <br />deadband to heating - 1OF (0.5 °C) as the secondary changeover <br />deadband. <br />• Configurable from 1 — 4 °F (0.5 — 2 °C) <br />v) A weighted demand shall be configurable for the Averaging and Vote <br />methods. <br />2) Fixed Method <br />i) Changeover evaluated by room temperature and setpoint of the repre- <br />sentative indoor unit (first registered indoor unit in changeover group) <br />in the changeover group even when it is not operating (must be in <br />Cool, Heat, or Auto mode) <br />ii) Changeover affects all indoor unit groups in the changeover group. <br />3) Individual method (recommended for Heat Recovery Systems) <br />Reece, Noland & McElrath, Inc. 239500-73 Orange County Board of Elections <br />Orange Co., NC 05/04/18 <br />