=== dc2020-12-0026-guidelines-pages-21.ppm === 5.6 5.7 Table 11. Piping System Design Maximum Flow Rate in Gallons Per Minute ( GPM) Table 6.5.4.6 Piping Spsdon7 Dosign Maximum Flow Hate in GPM Variabie Spend Other 4 Varinkle Speed uM THEE fas “nw Pa “Oa seu te ont? THs “Ris RIE Aad winds Maman weedy apes WEES Vaiss. a ts ta ths RQAS 15 Als cre Sree So tk are Source: ASHRAE Standard 90.1-2019 C. Variabie Flow Pumping systems that are provided with control valves designed to modulate or step open or close, depending on the load, shall be required for variable fluid flow. The system shall be capable of reducing system flow to 50% of design flow or less. Flow may be varied using variable speed-driven pumps, multiple stage pumps, or pumps riding their performance characteristic curves. Pumps with steep performance curves shall not be used since they tend to limit flow rates. Variable speed or staged pumping shall be employed in large pumping systems. Exceptions: e System where a minimum flow greater than 50% of the design flow rate is required for the proper operation of the equipment served by the system. e Systems that serve only one control valve. Air Distribution Systern Design Criteria A. Generai The temperature and humidity of the air within the conditioned space shall be maintained at an air movement from 0.20 to 0.30 m/s (39 fpm to 59 fpm). The air in such conditioned space(s) shall at all times be in constant motion sufficient to maintain a reasonable uniformity. of temperature and humidity but shall not cause objectionable draft in any occupied portion(s). In cases where the only source of air contamination is the occupant, air movement shall have a velocity of not more than 0.25 m/s (49.2 fpm) as the air enters the space. Controls A. System Control 1. Each air-conditioned system shall be provided with at least one control device for temperature regulation. . 2. All mechanical ventilating system (supply and exhaust) equipment, either continuously operating or not, shall be provided with readily accessible Page 21 of 74 === dc2020-12-0026-guidelines-pages-22.ppm === manual and/or automatic controls or other means of volume reduction, or shut-off when ventilation is not required. B. Zone Control 1. Each air-conditioned zone shall be controlled by individual thermostatic controls responding to temperature within the zone. 2. Systems that serve zones that can be expected to operate non-simultaneously for more than 750 hours per year (i.e. approximately 3 hours per day on a 5- day week basis) shall include isolation devices and controls to shut off the supply of conditioned air to each zone independently. isolation is not required for: a. Zones expected to operate continuously b. Systems which are restricted by process requirements c. Gravity and other non-electrical ventilating systems that may be controlled by readily accessible manual dampers. C. Control Area 1. The supply of conditioned air to each zone/area shail be controlled by an individual control device responding to the average temperature within the zone. Each controlled zone shall not exceed 465 m? in area. 2. For buildings where occupancy patterns are not known at the time of the system design, such as speculative buildings, isolation areas may be pre- designed. : 3. Zones may be grouped into a single isolation area, provided the total conditioned floor area does not exceed 465 m? per group, or includes more than one floor. D. Temperature Controls Where used to control comfort cooling, temperature controllers shall be capable of being set locally or remotely by adjustment or selection of the sensors, between 23°C and 27°C, or in accordance with local regulation. E. Thermostat Location of the thermostats in controlled zones shall measure a condition representing the whole space and shall not be affected by direct radiation, drafts, or abnormal thermal conduction or stratification. F. Building Automation System Buildings with an air-conditioning system with a capacity of 1053 kW (300 TR) or larger shall be provided with building automation systems with software that will optimize, monitor, and control mechanical and electrical equipment with complete data-logging of its operational performance and maintenance schedule. G. Germicidal Irradiation and Filtration System for AHUs and FCUs . A germicidal irradiation filtration system is needed for air handling units (AHUs) and fan coil units (FCUs) for efficient disinfection. A High Efficiency Particulate Air (HEPA) Page 22 of 74 === dc2020-12-0026-guidelines-pages-23.ppm === filter or Minimum Efficiency Reporting Value (MERV)13 filter and above would increase the static pressure of the equipment blower; thus, increasing the blower horsepower is needed to operate the AHU and FCU. With ultraviolet germicidal irradiation (UVGI) and MERV 6 filters, the increase in blower horsepower is no longer necessary; hence, the current blower can still be used. 5.8 Chiller Plant Insulation A. All chilled water piping shall be thermally insulated in accordance with Table 21 to prevent heat gain and avoid sweating on the insulation surface. The insulation will be suitably protected from damage. B. The chiller surface, especially the evaporator shell and compressor suction line(s), shall be insulated to prevent sweating and heat gain. Insulation covering surfaces on which moisture can condense, or those exposed to ambient conditions, shall be vapor-sealed to prevent any moisture seepage through the insulation, or to prevent condensation in the insulation. Exceptions: 1. Piping that conveys fluids that have not been cooled through the use of fossil fuels or electricity 2. Piping at fluid temperatures between 20°C and 40°C 3. When the heat gain of the piping without insulation does not increase the energy requirements of the building C. For materials with thermal resistance greater than 0.032 m?°C/W-mm, the minimum insulation thickness shail be as follows: 0.032 x thickness in Table 20 t = actual R value Equation 6.1 Where : t = minimum thickness in mm R = actual thermal resistance, m2°-C/W-mm D. For materials with thermal resistance lower than 0.028 m2 °C/W-mm, the minimum insulation thickness shall be: 0.028 x thickness in Table 20 t= actual R value Equation 6.2 Where: t = minimum thickness in mm R = actual thermal resistance, m2°-C/W-mm 5.9 Air Handling System Insulation A. All air handling ducts and plenums installed as part of the air distribution system and which are outside of air-conditioned spaces shall be thermally insulated , Page 23 of 74 === dc2020-12-0026-guidelines-pages-24.ppm === sufficiently to minimize temperature rise of the air stream within them, and to prevent surface condensation. Insulated ducts located outside of buildings shall be jacketed for rain tightness and for protection against damage. Air ducts or plenums within air-conditioned spaces may not be insulated if the temperature difference (TD) between the air outside and within the ducts or plenum would not cause surface condensation. Due consideration shall be made to the dew point temperature of the air surrounding the ducts or plenums. The required insulation thickness shail be computed using insulation material having resistivity ranging from 0.023 to 0.056 m?. °C/W-mm and the following equation: kRs (Dp —to) (Db-Dp) Equation 6.3 Where: Db = ambient still air-dry bulb temperature, °C © Dp = dew point, °C To = operating temperature, °C Rs = surface thermal resistance = 0.115 m? °CAV-mm k = mean thermal conductivity, W-mm/ m?°C L= thickness, mm Exceptions: 1. When the heat gain of the ducts, without insulations, shail not increase the energy requirements of the building 2. Exhaust air ducts B. The thermal resistance of the insulation, excluding film resistance, shall be: TD mocncmn enn nnnnn = m2°C/W-mm 347 Equation 6.4 Where: TD = temperature differential in °C 5.10 Air Conditioning Equipment A. Minimum Equipment Performance Air conditioning equipment shall have a minimum performance corresponding to the rated conditions shown in Table 2. Data furnished by equipment suppliers or manufacturers certified under a nationally recognized certification program or rating procedure shail be acceptable to satisfy these requirements. 1. Performance Rating The performance rating of the air conditioning equipment with cooling capacity up to 50,000 kJ/hr (47,391 BTU/hr) or 14 kW (3.95 TR) shall be measured through the Cooling Seasonal Performance Factor (CSPF). The CSPF shall not be less than those quoted in the two-star range in the Page 24 of 74 === dc2020-12-0026-guidelines-pages-25.ppm === 5.11 current Energy Efficiency Performance Rating for Room Air Conditioners table (see Table 13) in Annex D.1 - Particular Product Requirements: Air Conditioners of the DOE’s Philippine Energy Labeling Program. Table 13: Energy Efficiency Performance Rating for Room Air Conditioners (2020) Cooling Seasonal Performance Factor (CSPF) PO FEPR 33a to 999KW | 1OOKW to tae One Star 3.08 to 2.31 2.84 to 3.1) 2 34 Two Stat 3.32 0 3.55 342 te 2.42 312 to 3.42 Three Star 3.43 to 3.73 3.43 to 3.73. Four Star 3.74 to 4.00 3.74 ta 4.00 Source: Annex D.1 — Particular Product Requirements: Air Conditioners, DOE Department Circular No.: DC2020-06-0015 Performance Rating The performance rating of the air conditioning equipment above 14 kW (3.95 TR) shall be measured by its EER or kWe/TR, whichever is applicable. The EER shall not be less than those quoted in Tab/e 23, while kWe/TR shall not be greater than the figures in the same table. a. Field-Assembled Equipment and Components When components from more than one supplier are used as parts of the air conditioning system, component efficiencies shail be specified based on the data provided by the suppliers/manufacturers, which shall provide a system that complies with the requirements of the subsection on Minimum Equipment Performance. , b. Air Conditioning Equipment Controls Air conditioning equipment shall have a means of controlling its capacity based on load requirement. Heat Recovery Whenever there is a big demand for hot water requirement and if economical, heat recovery shall be adopted in the air conditioning system condenser heat. Another would be using Enthalpy Recovery of Exhaust Air or Energy Recovery Ventilation for exhaust air. A. Enthalpy of exhaust air All buildings with centralized air supply system shall use enthalpy recovery wheel or energy recovery ventilation with efficiency of at least 60% of 90% exhaust air. When buildings have outside air or fresh air supply and they extract system through mechanical means, heat exchangers can use the air extracted from the building area Page 25 of 74 === dc2020-12-0026-guidelines-pages-26.ppm === 5.11 to pre-condition the incoming outdoor air. This process takes into account the fact that the extracted air is usually already conditioned, and therefore colder and drier. Enthalpy recovery is the process of recovering some energy from the building exhaust air stream to pre-condition the fresh air intake. Figure 2: Circulation of Outdoor and Indoor Air in an Enthalpy (Energy) Recovery Ventilation heat exchanger or enthalpy care fan or blower incoming . - ae unconditioned indoor “state air “fresh” outdoor air leaving the building preconditioned “fresh” ait ta nears incoming unconditioned “stale” indoar air fan or blower Figure 3: Enthalpy or Heat Recovery Wheel ara Quldeor air Arete oar Wheed Tyseley En dreaiest caer Return ear Thermal Comfort in Non-Air-Conditioned Buildings A. Generai Principles of Thermal Comfort The main variables that affect human comfort are as follows: dry bulb temperature | relative humidity or wet bulb temperature air movement ventilation and aAhwWN> thermal radiation from hot surface (ceiling, walls, and glass windows). To a lesser extent, certain other factors also affect human comfort like indoor air . quality. B. When cross ventilation in a room is assured, the relationship between ventilation rate and design wind speed is governed by the following equation: Q=17CeVA Equation 6.7 Where: Q .__: ventilation rate inm?/min Page 26 of 74 === dc2020-12-0026-guidelines-pages-27.ppm === Ce : effectiveness of opening (Ce is assumed to be 0.5 to 0.6 for perpendicular winds and 0.25 to 0.35 for diagonal winds) Vv : design wind speed in km/h A : area of opening inm? 1. The design wind speed for a particular type of structure, locality, and orientation has to be duly corrected to allow for height and screening effects of other buildings. The co-efficient of discharge C. is found to decrease fairly rapidly with an increase in the distance between the two openings in series, i.e., with an increase in room width. At 5.5 m, it will level off to about 0.47. In Equation 6.7, Ceis used to modify the external wind speed. To determine the wind velocity near a building, the wind available at the time and height of the building, as well as the velocity gradient due to the ground friction, shall be considered. A general equation, known as the ‘Power Law’ is given by Equation 6.8: Zg Equation 6.8 Where: Vz : velocity at height z, m/s Vg : gradient velocity, m/s Z : height,m Zg : gradient height, m a : a power index as given in the following table Table 14: Values of‘a’” Open country Moderately rough. wooded country, small town Rough, center of large town Source: Guidelines on Energy Conserving Design of Buildings, 2007 2. Natural Ventilation by Jack Roof and Roof Ventilator a) The performance of roof ventilators is normally rated in terms of speed and indoor and outdoor temperature differential to take into account the two natural motive forces of ventilation: thermal force and wind effect. The performance for roof cowls can be rated in the simplified equations as follows: Q=208AV Equation 6.9 Where: Q= ventilation rate (m3/h) A= throat area of ventilator (cm?) V= wind speed (km/h) Page 27 of 74 === dc2020-12-0026-guidelines-pages-28.ppm === b) A jack roof has poorer ventilation performance. However, assuming that a jack roof is about 50% as efficient as a cowl ventilator since the windward side of a jack roof does not act as an exhaust opening, the net area of jack roofs required per meter run of a building is about 1.2 m? for a building width of 18 m. c) The intake fresh air louver shali be at 1 meter above the floor so that the fresh air with lower temperature pushes up the hot air up to the roof ventilator/jack roof ventilator. C. Provision for Natural Ventilation and Lighting Note: The requirements below are subject to compliance with the provisions of Easement of Light and View of the Civil Code of the Philippines, specifically Articles 667 to 673. 1. In natural regulations, it is specified that every building shall have: a. natural lighting through windows, skylights, fanlights, doors, and other approved natural light transmitting media; and b. natural ventilation through windows, skylights, fanlights, doors, louvers or similar ventilation openings. 2. In general, openings facing the sky, street courtyard, or air well shall be considered as acceptable sources of natural lighting and ventilation. 3. In the case of a building other than a factory or warehouse, any part of the building within 9 m from an acceptable opening is considered adequately ventilated by natural means. 4. In the case of a factory or warehouse, the maximum effective coverage of any window and other openings on an external wall is 12 m from the opening, whereas the coverage of any jack roof or other openings on the roof is 9 m, measured horizontally from the opening. 5. In addition; every room in any building shall have natural lighting and ventilation through one or more sources having an aggregate of not less than x percent of the floor space of the room, of which at least y percent shall have an opening to allow free uninterrupted passage of air. The respective values of x and y are given in Table 24 according to the types of occupancy or types of usage of the room. 6. In the case of public garages, two or more sides of the garage shall have an opening for cross ventilation and the area opening will be at least 50% of the area of the wall where it is located. 7. Enclosed parking garage ventilation systems shall automatically detect contaminant levels by using supervisory control and data acquisition (SCADA) of building management systems (BMS); this is a must for energy efficiency. An induction (jet fan) ventilation with an_ electronically commutated (EC) motor shall be used in basement parking garages due to the following: Page 28 of 74 === dc2020-12-0026-guidelines-pages-29.ppm === a) Effective dilution of contaminants within the car park environment as compared with the ducted system b) The car park is too large and too deep to ventilate naturally. c) Slab penetrations can be reduced. No need for ventilation plant rooms. d) Capital cost savings can be found through reduced car park height - and less site excavation, less concrete and steel. 8. For terrace houses having a depth greater than 12 m, permanent ventilation from front to rear shall be provided to facilitate cross ventilation by suitable vents in all front, back and cross walls at each floor. Such vents shall have a net opening area of not less than 0.4 m? each. D. Mechanical Ventilation 1. Where site conditions dictate that the normal requirements for natural lighting and ventilation cannot be met, the building regulations may allow the use of mechanical ventilation as substitute. 2. According to the regulations, the quantity of fresh air supply for mechanical ventilation of any room or space in a building shall be in accordance with the specified rates in Table 25. Unless justified by exceptional circumstances, the ventilation rate shall not be exceeded by more than 30%. Figure 4: Wall Mounted Canopy Figure 5: Single Island Canopy Page 29 of 74 === dc2020-12-0026-guidelines-pages-30.ppm === Figure 8: Eyebrow ‘Figure 9: Pass-over Table 15: Air Intake Minimum Separation Distance Table 5-1 Air intake Minimum Separation Distance - Object Miainem Distance. 1 mt © loss 2 at ce tostectiel cater Mtede Chas Vin eetsunet rchet eatiet Sih Class 4 ait es aust religt eattet Mitty Cemvling teen er cubaanest MOS Coreling tenner uttike ot besatty Driveway, street. or paehing place oataes entry, sutormmtile beading arca, oc dine a ques Sirebege tomes peck np ere, Goemmvers Phiwbing conte teanmating atieast TO (l oetabove the bevel ol the outdoor an ivtake Plumbing sents terminating hess than fb) met above the level of the outdone ar intake Raol, bevivaped yrade oe other