B-rated water heaters

Edited by Eamonn Ryan

The following is a Tech Talk presented by Adriaan Myburgh on B-rated geysers – a term that has been abused or misinterpreted.

 It is a legal requirement in terms of VC 9006 that all geysers must have an energy efficiency rating of at least class B. It is also a requirement in terms of VC 9006 that all geysers must have a LOA issued by NRCS.It is a legal requirement in terms of VC 9006 that all geysers must have an energy efficiency rating of at least class B. It is also a requirement in terms of VC 9006 that all geysers must have a LOA issued by NRCS.

Only some geyser suppliers currently offer geysers that comply with the class B requirement and/or a LOA. A sales permit may be issued by the NRCS. In layman’s terms a sales permit can be regarded as a LOA.

Should the installation be regarded as compliant if a geyser without class (without NRCS or a sales permit) is installed? What documentary evidence should be provided to the auditor or inspector to verify the validity? The most important documentation is the SANS 151 – the standard that geysers get tested – to be awarded the Mark or to be listed as complying. 

pirb to Barker Insurance

SANS 151

6.6 Standing loss

6.6.1 Standard and heat pump water heaters

The standing loss per 24 hours, determined in accordance with 7.4.3 shall not exceed the values given in columns 2, 3 or 4 (as relevant) of table 3, appropriate to the nominal capacity of the water container given in column 1, or the value marked on the water heater (see 8.1.1 (e)) whichever is the lower, or obtained by interpolating between the two values on either side of the marked rate capacity.

6.6.2 Solar (without solar collector) water heater

The standing loss per 24 hours, determined in accordance with 7.4.3 shall not exceed 75% of the value given in column 2, 3 or 4 of Table 3 (or obtained by interpolating between the two values on either side) of the marked capacity of the water container in column 1 or the valuer marked on the water heater (see 8.1.1 (e)).The solar heater must also comply with SANS 1307 (which governs the system created between the collector and the geyser).

See Table 3:

No person may sell, import or manufacture a commodity to which a compulsory specification applies if it does not meet the requirements of the applicable technical regulation. Hot water storage tanks for domestic use can only be imported, sold or manufactured if it has a valid letter of authority. 

What are the requirements for a B rating on a geyser?

The polyurethane insulation between the inner cylinder and the outer galvanised casement is 128% thicker, resulting in the hourly standing heat loss decreasing from 108 watts per hour to 50 watts per hour, a 50% decrease on the 150ℓ geyser. A lower energy loss is a more efficient electric water heater. B rating energy efficiency.

As for other standards:

SANS 10400-XA

4. Requirements

4.1 Hot water supply

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:

  1. 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
  2. if solar water heating systems are used, these shall comply with SANS 1307, SANS 10106, SANS 10254 and SANS 10252-1.

4.1.2 Requirements for water installations in buildings shall be in accordance with SANS 10252-1 and SANS 10254

4.1.3 All hot water service pipes shall be clad with insulation with a minimum R-value in accordance with table 1.

SANS 10254:2017

4.1.3 Specific requirements for assembly

The assembly shall comprise the appropriate of the following:

  1. For both cold and hot water supply: Pipes and fittings, the type, application and quality of which shall comply with the requirements of SANS 4427-2, SANS 4427-3, SANS 15874-2, SANS 15874-3, SANS 15875-2, SANS 15875-3, SANS 15876-2, SANS 15876-3, SANS 15877-2 and SANS 15877-3, as relevant, and other pipes and fitting systems deemed acceptable in SANS 10252-1.
  2. A fixed storage water heater that complies with SANS 151.
  3. For closed water heaters: A pressure control valve, an expansion control valve, a safety valve (temperature and pressure control) and vacuum control valves, all of which comply with SANS 198.

This must be done to manufacturer’s specifications.

SANS 1352:2012

4.1.3 Specific requirements for assembly

4.1.3.1 Materials, components, fittings and fixtures shall be so selected that they are suitable for the expected conditions of use and shall bear acceptable markings for the purpose of identification. All plastic components exposed to direct sunlight shall be protected against ultraviolet (UV) radiation.
4.1.3.2 For both cold and hot water supply lines and the heat pump primary circulation loop pipes and fittings, the type and quality of which shall comply with requirements of SANS 10252-1.4.1.3.3 An approved air source water heating heat pump unit shall be used.
4.1.3.4 The storage water heater shall comply with SANS 151.
4.1.3.5 Drain valves for water heaters shall comply with SANS 1808-53.
4.1.3.6 All pressure control valves, expansion control valves. Safety valve (temperature and pressure control) and vacuum control valves, shall comply with SANS 198.

pirb.cocx to IOPSA

Municipal by-laws:

Technical requirements for a water installation39 (1) Notwithstanding the requirement that a certificate be issued in terms of section 36(3)(c), water installations must comply with SABS Code 0252 Part 1 and all fixed electrical storage water heaters must comply with SABS Code 0254. A very high proportion (perhaps as much as 90%) of municipalities have similar requirements.

The municipal water by-laws and SANS documents require that the storage water heater must comply with SANS 151, and do not mention class B requirements. The current SANS 151 does not have a pass/fail criteria of class B, but a lower standing loss requirement in Table 3. VC 9006 has two requirements, namely that storage water heaters must comply with both SANS 151 and Class B. Therefore, the VC requirements are contradictory until SANS 151 standing loss requirements are changed to accommodate Class B requirements.

This means suppliers and installers that do not have the necessary documentary evidence will be at risk of prosecution by the NCRS. 


 


Click below to access the digital publication:

08 Aug PA 250

(please ensure you are registered and logged in first)

Advertising
Advertise on Plumbing Online

PA PlumbdrainLogo100 PlumbingOnline150 TP

Product of

IMD logo White

Interact Media Defined (IMD), is one of South Africa’s leading multi-media magazine publishers READ MORE

Talk to us

JHB T : +27 (0) 11 579 4940
CPT T : 0861 727 663
E : admin@interactmedia.co.za

13A Riley Road, Bedfordview,
South Africa 2007

PRIVACY & COOKIE POLICIES

Cookie policy
Privacy & Cookie policy
Privacy policy

© Interact Media Defined