VE 6.4.0.5: Thermal / Systems Pack 1. Tabular Room Data editing for thermal properties There is a new button in Apache, UK Part L2, and PRM Tabular Room Data. This tool represents a real productivity enhancement to model data entry and review. It contains many useful items: Rapid data input Rapid data review Copy / Paste (to/from excel) Filters only show the data of interest Fully customisable tab setup (add, remove columns, re-order etc) Multi-room edit/review Edit/Review variant model room data. Perhaps the key benefit of tabular edit is the productivity gains it will provide for large project review and data modification. Key features include rapid data input, rapid data review and crucially, a copy and paste facility allowing data to be pasted directly to and from excel. You can use left-click, right-click, multi-select (shift / ctrl) etc. to modify and access data. Other key features are the ability to apply filters, allowing users to view only the data of interest. When filters are on, the column heading to which the filter is applied will contain a blue bar. Hovering over this presents the user with a balloon tip summarising the current filter.
2. ApacheHVAC There are a significant number of enhancements to the HVAC functionality. Prototype systems library Heat sources: Hot water loop, Generic heat source, inbuilt (non-networked) Heat pumps Solar water heater (on Hot water loop) Advanced heating coil Air-to-air heat pumps Chilled water loop: integrated Waterside economizer Chilled water loop: heat rejection by Fluid cooler Over-capacity Hot water & Chilled water loops Alternate system schedules: enhancements Prototype systems library Instead of loading all the predefined prototype systems at the same time, you now import them one at a time, by clicking the new Library button in the toolbar. (The S button is retained, but now only used to either select entire system(s) or edit their Descriptions). In the library interface, you can specify the import placement by selecting the relevant to-the-right or below arrow buttons. Note that the 12 PRM-specific systems are distinguished, by both name and icon, from the general-purpose prototype systems. There is also a wider variety of systems available than in previous releases.
Common pipe Absorption chiller DHW Radiator Simple coil Advanced coil In this release all the library systems share a common set of heating/cooling plant equipment (of which each system only uses part). Normally an import on top of another will *not* duplicate the plant, but there are options to override this for heating and/or cooling. This would only be used occasionally, in the specific case where some or all of your current network s plant has already been modified or sized, and you would like the coils in the imported system to be served instead by the original, unmodified, plant. Heat sources The Heat source list now lists two different types of Heat source, each with associated heating equipments: 1. Hot water loop: used to model heat sources involving hot water. Heating equipments are switched in according to a user-specified sequencing scheme, and sized on the basis of user-specified load percentages. 2. Generic heat source: used to model other types of heat source, such as electrical resistance, furnace, steam loop etc. In this case there is a single (Part load curve) heating equipment and hence no equipment sequencing. The associated heating equipment is of two types: 1. Hot water boilers (HWB): associated with Hot water loop only, in any number. 2. Part load curve heating plant (PLE): Hot water loop may have any number but a Generic heat source has one only. In addition to the above heating equipment, a Hot water loop may have a Solar water heater and/or an Airto-water heat pump (AWHP). Please refer to the conceptual configuration below. Key: CHR water air AWHP T lbt CHP V b Secondary pump T ldb g l PLE 1 PLE 2 HWB 1 HWB 2 Primary pump T edb g e Heat sources Solar water heater Hot water loop
In ApacheHVAC the Heat sources list now appears as below, with the different types of Heat sources, and attached heating equipments, all indicated by four different types of icon. The (single) Heat source designated to serve DHW loads, if any, is also indicated by red text. Hot water loop
As shown by the dialog tabs above and below, many of the parameters that were previously defined within an individual Hot water boiler are now shared among all the boilers in a loop, and therefore are now defined at the Hot water loop level. Please refer to the ApacheHVAC manual for more details. Note that Heat pumps are no longer network objects. When upgrading an existing HVAC network to version 6.4.1, a (networked) heat pump whose backup is a Hot water boiler is upgraded to an Air-to-water heat pump attached to a Hot water loop (whose single Heating equipment is the old Hot water boiler). In the network the pump is replaced by a simple connector.
The final Hot water loop tab (below) is conceptually similar to that for the existing Chilled water loop. It defines the Heating equipment set, and its sequencing and autosizing. Generic heat source The Generic heat source edit dialog is shown below. As already mentioned above (under Hot water loop), parameters such as Condenser heat recovery and CHP, that were previously defined within the Part load curve (Heating equipment), are now defined at the Heat source level. Like the Hot water loop, a Generic heat source may have a heat pump attached, but in this case it functions as an Air-source heat pump. When upgrading an existing HVAC network to version 6.4.1, a networked heat pump whose backup is a Part load curve heating plant is upgraded to either: an Air-to-air heat pump (new separate object, described below) whose backup is a Generic heat source (upgraded from the old Part load curve). or under certain circumstances (see ApacheHVAC manual for more details), an Air-to-source heat pump attached to a Generic heat source (upgraded from the old Part load curve). In both cases the pump (being no longer a network object) is replaced by a connector in the network.
Solar water heater A solar water heater in a Hot water loop is defined in exactly the same way as in the Apache view:
Advanced heating coil Paralleling the recently introduced Advanced Cooling coil modelling, there is now an Advanced heating coil model. This model makes the assumption that it is served by hot water, therefore only Hot water loops are available for selection as the serving Heat source. Unlike Advanced cooling coils, Advanced heating coils are autosized by Apache only; there is no manual sizing option.
Air-to-air heat pump The Air-to-air heat pump (AAHP) is a new component type. Instances of this type are intended to serve Simple heating coils, in place of an ASHP. The Edit dialog for an AAHP is shown below. The Backup heat source is limited to Generic heat sources, but now many pumps can share the same backup. Furthermore the use of a backup is now optional. Another difference from the old ASHP is that the Output performance values are now expressed as percentages of the maximum value (bottom row).
Chilled water loop: integrated Waterside economizer The new IWSE model enhances the current Waterside economizer modelling capability to provide for waterside economizer operation as a pre-cooling device in conjunction with a chiller set. The v6.4.1 implementation of the IWSE shares the heat rejection condenser water loop and tower with an Electric Water Cooled chiller.
Chilled water loop: heat rejection by Fluid cooler A fluid cooler is now available as an optional substitute for a cooling tower as the heat rejection device in a chilled water loop. There are two types, or modes of operation, of a fluid cooler. These depend on the wetting conditions of the surface of the coil in the stream of outside air. A dry fluid cooler is one where the coil is permanently dry. This type of cooler tends to be used in areas where there are restrictions on the availability of water. A wet/dry fluid cooler is one where the coil is sprayed with water to provide additional evaporative cooling. To prevent freezing of the water on the coil, these coolers can also operate as a dry fluid cooler.
Over-capacity Hot water & Chilled water loop Improvement has been made to the modelling of undersized or overloaded heating and cooling sources. Previously, if equipment (heating coils, cooling coils, etc.) on a heating or cooling loop demands more heating or cooling than the source is designed to provide, the demand is always met the source performing above its design capacity. Now deficiencies in capacity at the heating and cooling sources hot water loops and chilled water loops will feed back to the air handling components they serve. In other words, the heating and cooling sources will always try to raise or reduce the return hot or chilled water temperature to the target supply water temperature. If the target supply water temperature cannot be reached, the return water temperature will be raised or reduced in response to the shortfall. The adjusted water supply temperature only affects certain types of component. Advanced heating and cooling coils respond to the adjusted supply temperature by reducing the amount of heating or cooling they are able to deliver. Other components, including simple heating and cooling coils, radiators and chilled ceilings, do not respond to the adjusted temperature. Their loads are dictated solely by conditions in the airside system or the building. Likewise, any domestic hot water loads placed on a hot water loop, and loads placed on this loop by absorption chillers, are insensitive to the hot water loop supply temperature. Generic heat sources continue to follow the old policy: for these heat sources a shortage of capacity does not feed back to the components they serve. Alternate system schedules: enhancements The system schedules dialog has been modified to allow the user to create alternative profiles. This will allow the user to rapidly generate and edit multiple sets of alternative profiles. These newly created profiles can then be assigned to various scheduling scenarios for HVAC, setpoints etc.
BREEAM Navigator A BREEAM Navigator has been created which makes assessing BREEAM 2008 credits much easier. It assists with the calculation of 42 credits and 6 innovation points, covering: Daylighting Indoor Air Quality Thermal Comfort LZCT Emissions and Free Cooling Water and Recycling Materials (Specification) Materials (Responsible Sourcing) Supported schemes are Offices, Schools, Higher Education, Healthcare and Retail:
LZCT (ENE 1 and ENE 5 credits) The BREEAM calculator allows extensive configuration of Renewable, low carbon, and green power options (select the Choose LZCT option in the navigator). When selecting any LZCT technologies through this interface, please ensure they are not also defined as part of your Apache System or Apache renewables, else the double definition will cause incorrect simulation results.
Emissions and free cooling (ENE 1 and ENE 10 credits) The credit calculation for Emissions (ENE1) credit requires the completion of an EPC Compliance simulation. This requires a CIBSE weather file. For those users who do not have a Compliance licence, a new interface is provided for basic Compliance configuration (Simulation settings): For free cooling (ENE10) credit (only applicable for schools and higher education), a configuration screen allows the user to select the free cooling options that will be deployed (Confirm free cooling strategies):
Water and water recycling (WAT1 and WAT5 credits) The water appliances can be defined through the Edit appliance data option in the navigator. This will show the following entry screen:
Materials specification and responsible sourcing (MAT1 and MAT5 credits) The materials and constructions used within the building must be provided with a Green Guide rating, and given an appropriate Ecopoints building type. This is done through the new Edit Green Guide ratings entry in the navigator, which launches the dialog below. The MAT5 credit requires further information not gathered by the <VE> and therefore cannot be automatically calculated. However, the MAT5 materials report provides all the appropriate materials information for easy entry into the appropriate BREEAM calculator.