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19-06-2019 6:30 pm
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25-06-2019 6:00 pm
Category:  Johannesburg
ACRA (Air Conditioning and Refrigeration Academy)

SAIRAC talks HVAC load estimation

The Johannesburg SAIRAC centre’s technical talk for April was entitled ‘HVAC load estimation – an engineer’s perspective’ and was extremely well attended.

The South African Institute of Refrigeration and Air Conditioning (SAIRAC) meeting took place at its usual Bryanston Sports Club venue and there was hardly an open seat in sight for the discussion of this topical matter.

Before the presentation got underway, Johannesburg centre chairman, Jaco Pieterse, handled a few formalities. He gave feedback on the very successful association golf day that took place in March and informed members and guests of all upcoming events and courses still planned.

Pieterse handed over various certificates to new members who were in attendance as well as to those who came to collect certificates for completed SAIRAC courses.

Charel Marais, the centre’s vice chairman, introduced the speaker – Deo du Plessis of Spoormaker & Partners, who is an ex-colleague. Du Plessis is an associate at the firm and is a professional engineer (PrEng). He holds a PhD and BEng in mechanical engineering and is also an ASHRAE associate. He has designed and implemented HVAC projects in various sectors and industries.

Deo du Plessis of Spoormaker & Partners was the speaker of the evening.Robert Fox of SAIRAC (centre) with two of the new members who received their certificates on the night: Jurgen Olivier (left) and NR Nevhutanda.A full house at the Johannesburg SAIRAC centre’s April technical meeting.Robert Fox of SAIRAC (back right) with some of the candidates who received certificates for successful completion of SAIRAC coursers. Back is Jurgen Olivier; front, from left are: Chris Toomey; Sion Lupapi; Danie Venter; Ruaan Smith; Tshifhiwa Tshivhase; and Pragasen Govender.

Du Plessis gave overview of the various elements that need to be taken into consideration when modelling and sizing HVAC systems at conceptual. He covered this at quite a high level, keeping things broad and focusing on how this affects and applies to contractors as well, not just consulting engineers.

The following elements were covered in his talk: walls; roofs; floors; glazing and shading; equipment; people; lighting; latent loads; operation schedules; partitions; as well as orientation and sun angles.

Du Plessis’s talk also looked at pitfalls to be on the lookout for and the risks of ‘rule of thumb’ load estimating from a consulting engineer’s point of view.

“The talk was essentially an introductory overview of the elements of HVAC loads, and is best suited for technical persons and contractors who wish to understand more about the various theoretical components important to successful HVAC designs,” he explains.

Everyone was all ears for Du Plessis’s talk and afterwards he got very positive feedback as guests seemed quite impressed at his simplified delivery of such a complex topic. There were a lot of questions for the speaker and the conversation carried on long after the talk was over…

Afterwards, members and guests enjoyed a meal prepared by the club and continued networking with old friends and new.

AdmirorGallery 5.2.0, author/s Vasiljevski & Kekeljevic.
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