Plumbing Africa January 2018 | Page 71

TECHNICAL 69 Retrofitted solar geysers and SANS 10400-XA requirements The requirements of SANS 10400-XA for the installation of retrofitted solar geysers on new property developments have been causing some confusion. By Mark de Wet With retrofitted installations being cheaper, developers are opting for the retrofitted systems, but they are unaware that the installation will not be compliant with the requirements of SANS 10400-XA and SANS 1307. This also becomes problematic for the plumber issuing the PIRB CoC, as it will fail in an audit. WHAT DOES SANS 10400-XA REQUIRE? Functional regulation XA2: Not more than 50% of the annual volume of domestic hot water should be supplied by means of electrical resistance heating, i.e. 50% or more of the hot water used must be heated by energy sources other than electricity. So, with a standard electrical geyser being used as a solar retrofit installation, the standing heat loss on the cylinder does not allow for 50% alternative heating as the water in the tank cools down overnight, or during the winter season the geyser will be required to use an electrical element to heat the water, thus not allowing for the required 50% as per SANS 10400-XA2. If we take a closer look at SANS10400-XA, it states the following regarding solar hot water heating installations. 4.1.1 In order to comply with functional regulation XA2, contained in part XA of the National Building Regulations, the following guidance is provided: • The volume of the annual average hot water heating requirements shall be calculated in accordance with tables 2 and 5 of SANS 10252-1; and • If solar water heating systems are used, these shall comply with SANS 1307, SANS 10106, SANS 10254, and SANS 10252-1. Some might experience difficulty in grasping a complete picture of the solar water heating system and its installation requirements, because numerous normative referenced standards are not examined, which is where a lot of the detail resides. These include SANS 151, SANS 60335-2-21, SANS 10254, SANS 198, SANS 10152-1, as well as NRCS VC 8055 and VC 9006. SANS 10106 5.1.6, in turn, requires that the solar water www.plumbingafrica.co.za heating system must comply with SANS 1307. Therefore, the solar water heating system must comply with SANS 1307 — which includes the two main components of the collector and the storage tank (3.1.6), as well as all the prescribed control and safety valves, and pipework thermal insulation — and the installation i tself must comply with SANS 10106 (which covers many aspects as well). SANS 1307 specifies the tests, the design, and the performance of some of the components separately (like hail, condensation, and cover strength tests on the collectors; other tests on the storage tank; as well as tests on the components together as a system, such as thermal performance, standing losses, and freeze resistance). SANS 1307 compliance cannot be achieved by the sum of the individual components on their own, tested separately. There is no test in SANS 1307, or in any other SANS standard, for the thermal performance of the collector on its own. You cannot, therefore, test a collector on its own, mix and match it to any other storage tank, and then prove or certify compliance of such a combination as a SANS 1307 system. So, in conclusion, any inspectorate like the PIRB, the municipality, or any other inspection or approvals authority or body (for example the Department of Energy and CEF) needs proof in the form of a valid and current SANS 1307 system test report, mark certificate, or JASWIC listing and certificate. If a retrofit system is to be used at a new development, then a SANS 1307 test report will need to be provided by either the manufacturer, importer, or plumber doing the installation, and presented to the developer or consumer as proof that the complete installation is compliant and has been tested in full to the requirements of SANS 1307. The installation will also require the plumber to provide the consumer with a copy of the SANS 1307 test report and a PIRB CoC as per the requirements of SANS 10106. PA Mark de Wet Mark de Wet is the national technical manager at IOPSA. He is a qualified plumber and registered gas installer. He also sits on the SABS technical committees and working groups on behalf of IOPSA and the IOPSA National Executive Board, as well as being a PIRB inspector. SANS 1307 compliance cannot be achieved by the sum of the individual components on their own, tested separately. January 2018 Volume 23 I Number 11