16 DESIGN : DEAR PLUMBERS
Vollie Brink is one of the industry ’ s longest-serving wet services engineers . He continues to serve on SABS committees and has been involved in the Green Building Council ’ s Green Star rating system . Brink continues to consult for various organisations while enjoying a wellearned retirement .
Compliance is not negotiable !
By
D . S ( Vollie ) Brink Pr . Eng . MSAICE , MPMISA
One of the eleven outcomes for registration as a professional engineer , technologist , or technician , is to not accept work for which a person is not competent .
I have referred to this in past articles and sadly we have another example of a designer “ being instructed not to apply the legal requirements .”
“ Somebody ” sent me a drawing of a plant room for the ablutions hot water system of an industrial project and asked my opinion of the design of the plant and equipment .
I had a discussion with the designer and it became clear that the designer was fully aware of the legal requirements .
The designer was instructed to adhere to the following : 1 . To use the old type of “ electrical donkey ” to generate the hot water . This is in direct contravention of SANS10400-XA which allows that only 50 % of the hot water be generated by means of electrical elements , the rest must be generated by means of other nonelectrical means .
2 . Heat pumps comply with this requirement as it uses electricity but not for electrical elements and if it has a high COP such as a 2 or more , then the use of electricity is acceptable in terms of SANS10400-XA
The COP is the " Coefficient of Performance ” of the Heat-pump . In other words , if you have a heat pump with a COP of 2 , then you put in 1 kW and get out 2 kW
3 . It is important that the heat-pump be installed in a position where it gains the best ambient temperature to achieve the best COP .
4 . The designer was aware of the requirements of insulation of the piping system and the hot water vessels , which is also a requirement of SANS 10400-XA .
What is an Electric Donkey ? The “ Donkey ” was a vessel with water and full of electrical elements to generate hot water at a constant rate . The “ Donkey ” does not comply with SANS10400-XA and therefore cannot be used anymore unless it is revised to comply with SANS10400-XA .
It is also important that the heat pump be correctly specified to comply with the SANS10400-XA requirements and the specific SANS specifications of a heat pump .
The heat pump is only a part of the total hot water generation plant and must be correctly integrated into a complete hot water generation plant that complies with all relevant requirements and health and safety regulations . PA
“ The heat pump is only a part of the total hot water generation plant ..”
www . plumbingafrica . co . za January 2023 Volume 28 I Number 11