【Daily Question】Question from Issue 20150807
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Participation reward: 2 Wealth. Reward for correct answer: 9 wealth. Multiple-choice question: For a nine-story residential building designed with a individual heat metering system for central hot water heating, which of the following approaches is correct? (A) To ensure the flow rate in the indoor dual-pipe system, a self-acting differential pressure control valve is installed at the hot water inlet. (B) To extend the service life of the heat meter, the residential heat meter is installed on the return water pipe. (C) To prevent the heat meter from getting clogged, a filter is placed before it. (D) To maintain the heating capacity of the heating system, the calculations for the supply and return water pipes must take into account the heat loss caused by heat transfer to adjacent units. A new activity has started in the production area; the prizes are attractive, so hurry and participate: 【Production Through Summer】 – The production area has entered the “training during the hottest days of summer” mode
A, B, C. --------------
Choose ABC.:victory::victory:
(A) To ensure the flow rate in the indoor dual-pipe system, a self-acting differential pressure control valve is installed at the heat inlet
Choose BC. Explanation: In centralized heating systems as specified in 5.2.2–3, static hydraulic balance valves should be installed at the thermal inlet of buildings, and the hydraulic balance of the system should be adjusted accordingly. Whether to install a self-acting differential pressure control valve should be determined by the extent of changes in the pressure difference at the thermal inlet – in order to ensure proper operation of the constant temperature control valve and to prevent noise generation due to the pressure difference during shutdown. B. According to Civil Code 5.10.3, the flow sensor of the heat meter should be installed on the return pipe, which helps to extend the battery life and improve the performance of the instrument. According to the Warmth Code, the flow sensor of the interchangeable heat meter should be installed on the return pipe. However, this view was rejected by the civil regulations. C. According to \"Installation of Individual Heat Metering Systems for Central Heating with Hot Water\", 04K502-27, a filter is installed in front of the household heat meter; Figure 5-9 in Regulation 5.4.10 also shows that a filter is installed in front of the heat meter ； Clause 4.9.5.2 of the Warmth Code stipulates that a filter shall be installed in front of household heat meters. Therefore, C is correct. According to Article 5.2.10 of the Civil Code and Article 4.9.3 of the Heating Code, when determining the capacity of indoor heating equipment and the indoor piping in a heat metering system for individual households, the additional heating load resulting from heat transfer between adjacent households must be taken into account. Clause 7.1.5 of “Thermometry” stipulates that when selecting radiators for new buildings, the impact of heat transfer between rooms on the heating load should be taken into account. Option D is not selected because it is uncertain whether the \"supply and return water pipes\" mentioned are located inside the household.
For the design of a nine-story residential building with a individual heat metering system for central hot water heating, what is the correct approach? (BC) (A) To ensure the flow rate in the indoor dual-pipe system, a self-acting differential pressure control valve is installed at the heat inlet. (B) To extend the service life of the heat meter, the residential heat meter is installed on the return pipe. (C) To prevent the heat meter from getting clogged, a filter is placed before the residential heat meter. (D) To maintain the heating capacity of the heating system, the calculations for the supply and return pipes of the heating system must take into account the heat loss caused by heat transfer to adjacent households
The correct answers should be BC; for A, it depends on the specific circumstances
(C) To prevent the heat meter from getting clogged, a filter is installed in front of the residential heat meter. (D) To ensure the heating capacity of the heating system, the calculations for the supply and return water pipes of the heating system must take into account the heat loss caused by heat transfer to adjacent units