GAUTENG DEPARTMENT OF INFRASTRUCTURE DEVELOPMENT

Transcription

1 GAUTENG DEPARTMENT OF INFRASTRUCTURE DEVELOPMENT BUILDING ASSESSMENT REPORT HVAC FOR ABSA Building OCTOBER 2014

2 Report for Gauteng Department of Infrastructure Development HVAC Services Preliminary Report: Corner House Rev 2 October 2014 Table of Contents 1. INTRODUCTION Design Criteria and Specifications Scope of the Services Scheme Report PROJECT SUMMARY INSPECTION System Description Rooftop Packaged units Heat Pump VRV System DX Split type units Fresh Air Fan Systems Toilet Ventilation Basement Ventilation RECOMMENDATIONS HVAC... 7 i P a g e

3 1. INTRODUCTION The ABSA building is located at cnr. Fraser and Albertina Sisulu Streets, Johannesburg, Gauteng (see Locality Map). Figure 1 - Locality Map The project brief, as issued by Gauteng Funding Agency (GFA), was to conduct an initial assessment of the building HVAC infrastructure and systems of the ABSA building, and to provide recommendations regarding the repairs and renovations of the building. 1.1 Design Criteria and Specifications This project will be implemented in compliance with all the requirements of the National Building Regulations and SANS10400, with specific focus on Part O of the regulations (Lighting and Ventilation). 1.2 Scope of the Services Scheme Report This report deals with the HVAC services to be implemented based on the existing systems and proposed architectural changes to the building. This report is based on a visual inspection only of the applicable service installation. 1

4 2. PROJECT SUMMARY 2.1 Project Description The project comprises a multi-storey building, which has been divided to accommodate three separate tenants. Two of the tenants enter the building off Albertina Sisulu Street (Absa tenants and Absa bank), whilst the last tenant (Road and Rail Agency) enter the building off Fraser Street. The building has two basement parking levels, space for the bank, office space, as well as two roof levels. The previous Absa bank tenant occupied the entire ground and first floor level, allowing only a very small reception for the other tenants. Therefore, whilst the other tenants did have a ground floor reception, their actual office space only began on the second level. The ABSA building is a total of 12,045m 2. The building is currently occupied on some levels. Levels 8 and 9 have been vacated and are in a state of disrepair. 3. INSPECTION This report is based on a visual inspection only of the applicable service installation. 3.1 System Description The ABSA building is currently air conditioned by the following types of air-conditioning systems: Dunham Bush Rooftop DX Packaged Units. Daikin Heat Pump type VRV systems DX Split type Units (various makes) The rooftop packaged units located on the roof. The Split and VRV condensing units are situated in the open well of the building, Basement and roof. Air is distributed to the spaces via sheet metal ducting and grilles from the rooftop packaged units. Air from The VRV system is supplied to spaces my means of console type units and ducted fan coil type units. The split units consist of ducted fan coil type units, cassettes and midwalls. Filtered / treated Fresh air is introduced to certain areas of the building either by means of fresh air grilles located on the return air ducting to the rooftop packaged units or by means of individual mechanical fresh air systems. The basements are mechanically ventilated. 3.2 Rooftop Packaged units. The existing R22 Dunham bush units appeared not to be operating. 2

5 Figure 2 Rooftop Unit Figure 3 - Rooftop Unit 3.3 Heat Pump VRV System The Daikin R22 heat pump type system appeared not to be operating. The indoor units comprise wall mounted console type units and ducted fan coil units. The outdoor condensing units are positioned within the open well, on the roof and perimeter balconies. Although outdated, the condensing units appear to be in a reasonable condition. Figure 4 VRV Condensing Units Figure 5- VRV Condensing Units 3

6 Figure 6- VRV Wall mounted Console Unit Figure 6- VRV In-ceiling Fan Coil Unit 3.4 DX Split type units Various areas of the building are air-conditioned by means of DX split type units. There are a number of different makes and models of these units situated throughout the building. Some units seem to be operating and some appear to be beyond any state of repair. The indoor units comprise 4 way blow ceiling cassette units, ducted fan coil unit and midwall units. The outdoor condensing units are positioned within the open well, on the roof and perimeter balconies. Figure 7 DX Condensing Units 4

7 3.5 Fresh Air Fan Systems Fresh air is introduced to certain / various areas of the building either by means of fresh air grilles located on the return air ducting to the rooftop packaged units or by means of individual mechanical fresh air systems. Figure 12 Fresh air Intake Louvre to Rooftop Units Figure 23 Fresh air system 3.6 Toilet Ventilation Ablutions are naturally ventilated. It appears as though no mechanical extraction systems are installed. 3.7 Basement Ventilation The basements are mechanically ventilated. The ventilation systems appeared to be mostly intact with fans suspended at high level from the ground floor slab soffit. 5

8 Figure 25- Natural Ventilation via Openable Windows Figure 25- Natural Ventilation via Openable Windows Figure 27 Basement Extract exhaust fan Figure 28 Basement extract ducting / inlet grilles 6

9 4 RECOMMENDATIONS The remedial work required to meet the minimum national standard and reinstate the HVAC systems is recommended and a high level budgetary cost for the remedial work is presented. 4.1 HVAC 1. Remove and scrap all of the various air-conditioning systems. This includes for the rooftop units, VRV systems and DX split units. 2. Install new air-cooled chillers. 3. Install New HVAC Electrical DB. 4. Install new chilled water system, including pumps, Piping reticulation and valves. 5. Install new Chilled water fan coil units. 6. Install new Fresh air supply fans and ducting reticulation in compliance with SANS 10400: O. 7. Install new toilet extract system in compliance with SANS 10400: O and ensure correct balance between fresh and extracted air. 8. Install new basement ventilation system in compliance with SANS 10400: O and Rational Fire Design to unventilated areas. Repair existing fans and ducting where required. 7