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This post was last edited by hesonchang214 on 2020-4-6 at 17:09. Which of the following statements regarding the hydraulic calculation of hot water distribution networks is incorrect? A. The formula for the design flow rate in hot water distribution networks is the same as that for cold water systems. B. When calculating the design flow rate in hot water pipes, the hot water consumption rate for faucets and washbasins should be set at 0.15 L/s. C. The flow velocity in hot water pipes should be lower than that in cold water pipe systems. D. The head loss per unit length in hot water networks should be determined using the Haicheng-Williams formula, taking into account the effects of scaling and corrosion on the internal diameter of the pipes. Answer: B. Options A and D comply with Article 5.5.2 and Paragraph 1 of Article 5.5.4 of the current “Code for Design of Building Water Supply and Drainage Systems”, respectively. The description in option C is in accordance with the provisions of Articles 5.5.8 and 3.6.9 of the current Code for Design of Building Water Supply and Drainage. The hot water pipes have a long length and high head loss; in order to maintain pressure in the heating and cooling systems and keep the outlet water temperature stable, the flow velocity in the hot water pipes should be lower than that in the cold water pipes. Option B does not comply with the provisions of Note 1 in Article 3.1.14 of the current Code for Design of Building Water Supply and Drainage. The hot water consumption rate for mixers in washbasins should be set at 0.10 L/s when calculating hot water usage separately