The ahu tag is used model air handling equipment designed to heat or cool air. In Project Haystack, packaged rooftop units are considered a special class of AHU. Packaged units use the ahu tag, but should also specify the rooftop tag:
ahu // any type of air handler unit (built-up or RTU) ahu and rooftop // only packaged rooftop units (RTUs) ahu and not rooftop // only built-up custom AHUs
Tags
AHUs should always be marked as equip. The following HVAC specific tags are used on AHU records:
hvac: always specified to mark as an HVAC asset
rooftop: if the AHU is a packaged rooftop unit (RTU)
DualDuct: if the AHU has separate cold air and hot air ductwork. Dual duct AHUs should have two sets of discharge points identified with the coldDeck and hotDeck tags
boilerPlantRef: to associate the AHU with the boiler plant supplying its hot water or steam
chillerPlantRef: to associate the AHU with the chiller plant supplying its chilled water
I propose that a supplementary tag always be present (as in case of Roof Top Unit (RTU)) and to be filled with choice of; VAV, DualDuct DD, Constant volume CV, Multi-zone MZ, Outdoor Air OA, and Data Center DC (predominantly recirculating with cooling,heating,dehumidifying or humidifying).
For Boilers or Chillers that a similar sub-tag be added to indicate type chiller/boiler. Chillers; centrifugal, reciprocating, absorption, CO2 or refrigerant type. Boilers; Steam for heating STm, steam for process (high pressure)STmHP, Hot water HW, High Temperature Hot Water HTHW, Steam used for humidification SH.
The above are still general in nature but identify more specifically the type of equipment. Other variations such as terminal reheat might also be considered in the above.
With reference to the DualDuct systems, The terminal devices used for zone control are unique. They might be compared to two VAV devices operating in a supplemental way so as to mix two sources of air flow (hot air and cold air) to obtain a discharge temperature which will satisfy space requirements. At the same time,the total air delivered must be less than maximum flow to the space which also may drop to a low value due to occupancy variance. Therefore terminal devices associated with DualDuct applications are unique and will have close to twice as many values to display. Should have unique equipment tags
Brian FrankMon 23 May 2011
We already have a dualDuct tag to describe dual duct systems and to distinguish discharge sensors in the cool deck or heat deck.
Some of your suggestions for terminal units would most likely be captured explicitly by the marker tags. Note no models have been proposed for anything other than VAVs.
Winston Hetherington Wed 18 May 2011
Existing Docs:
Overview
The ahu tag is used model air handling equipment designed to heat or cool air. In Project Haystack, packaged rooftop units are considered a special class of AHU. Packaged units use the ahu tag, but should also specify the rooftop tag:
ahu // any type of air handler unit (built-up or RTU) ahu and rooftop // only packaged rooftop units (RTUs) ahu and not rooftop // only built-up custom AHUs
Tags
AHUs should always be marked as equip. The following HVAC specific tags are used on AHU records:
I propose that a supplementary tag always be present (as in case of Roof Top Unit (RTU)) and to be filled with choice of; VAV, DualDuct DD, Constant volume CV, Multi-zone MZ, Outdoor Air OA, and Data Center DC (predominantly recirculating with cooling,heating,dehumidifying or humidifying).
For Boilers or Chillers that a similar sub-tag be added to indicate type chiller/boiler. Chillers; centrifugal, reciprocating, absorption, CO2 or refrigerant type. Boilers; Steam for heating STm, steam for process (high pressure)STmHP, Hot water HW, High Temperature Hot Water HTHW, Steam used for humidification SH.
The above are still general in nature but identify more specifically the type of equipment. Other variations such as terminal reheat might also be considered in the above.
With reference to the DualDuct systems, The terminal devices used for zone control are unique. They might be compared to two VAV devices operating in a supplemental way so as to mix two sources of air flow (hot air and cold air) to obtain a discharge temperature which will satisfy space requirements. At the same time,the total air delivered must be less than maximum flow to the space which also may drop to a low value due to occupancy variance. Therefore terminal devices associated with DualDuct applications are unique and will have close to twice as many values to display. Should have unique equipment tags
Brian Frank Mon 23 May 2011
We already have a dualDuct tag to describe dual duct systems and to distinguish discharge sensors in the cool deck or heat deck.
Some of your suggestions for terminal units would most likely be captured explicitly by the marker tags. Note no models have been proposed for anything other than VAVs.