Paper format: National Exams, May 2018 — 07-Str-B6 Building Engineering and Services. Three hours, open book, one Casio or Sharp approved calculator. Six questions of equal value (20 marks each); five constitute a complete paper and only the first five appearing in the answer book are marked. All six are solved here. This subject contains no structural analysis at all — the cover page names it Building Engineering and Services, and every question is HVAC, building physics, acoustics or electrical services.
Reference texts (the books an open-book candidate should have on the desk for this subject):
- ASHRAE, Handbook — Fundamentals, 2021 — ch. 1 (psychrometrics, and the chart reproduced on page 5 of this paper), ch. 25–27 (thermal resistance of assemblies, surface films, air spaces), ch. 8 (sound and vibration).
- F. C. McQuiston, J. D. Parker & J. D. Spitler, Heating, Ventilating, and Air Conditioning: Analysis and Design, 6th ed. — ch. 3 (moist-air processes, coil bypass factor, reheat), ch. 5 (wall U-values), ch. 15 (refrigeration cycles).
- Y. A. Çengel & M. A. Boles, Thermodynamics: An Engineering Approach, 9th ed. — ch. 11 (vapour-compression refrigeration, R134a tables), ch. 14 (gas–vapour mixtures).
- D. Chadderton, Building Services Engineering, 6th ed. — room acoustics, site electrical distribution, ventilation systems for dwellings.
- National Research Council Canada, National Building Code of Canada (NBCC) 2020, Part 6 and Subsection 9.32; National Energy Code of Canada for Buildings (NECB) 2020.
- CSA C22.1, Canadian Electrical Code, Part I — Section 76 (temporary wiring on construction sites), Section 10 (grounding and bonding), Rule 26-700 (receptacle ground-fault protection).
Check — conventions adopted across this paper. (1) All psychrometry is worked at the 101.325 kPa sea-level barometric pressure printed on the supplied ASHRAE chart, using the standard moist-air relations rather than by scaling off the printed chart; the chart-read and calculated values agree to within the width of a pencil line, and calculating makes every number auditable. (2) Fan heat and duct gains are neglected, as the question intends: the supply-air state is taken as the state leaving the heating coil, and the return-air state as the room state. (3) In Question 3 the paper writes the second cycle as 4 → 1 → 2a → 3a → 4, reusing the label "4"; the state after throttling from 3a is not the same point as the state after throttling from 3, so it is called 4a here and the difference is exactly what changes the refrigerating effect. (4) Question 3 asks for "ideal COP" — taken as the Carnot COP between the stated evaporating and condensing temperatures, with the plotted vapour-compression cycle giving the "actual" COP and the ratio giving the COP efficiency. (5) Question 4 writes thermal conductivity in W/(m·°K); the degree sign on a kelvin is a typographic slip in the paper, and the units are read as W/(m·K). (6) Questions 2, 5 and 6 are answered in the Canadian frame — NBCC/NECB, CSA C22.1 and CSA/ANSI standards.
