8/11/2016

2.0 HVAC
2.1 General 2.1.3 Air-Conditioning
Standards
2.1 General 2.1.1 Definition of Air-
Conditioning 1.Cooling and De-humidifying

HVAC
2.2 Refrigeration for summer cooling, temperatures of 68
Cycle deg to 74 deg F and 50% relative
the simultaneous control of the
humidity are a frequent design average.
2.3 Types of Air- temperature, humidity, motion and
Conditioning purity of the air in a confined space. 2. Heating and Humidifying
Systems for winter cooling, temperatures of 70 deg

2.4 Air-Conditioning
2.1.2 Functions or to 75 deg F and relative humidity of 30%
to 35% are found most satisfactory.
Equipment Elements of Air-
Conditioning 3. Air Motion
2.5 Heating
air velocity should average 4.57 to 7.6
Systems
1. Cooling and de-humidifying of air meters per min measured 36 above the
2. Heating or humidifying of air floor.
2.6 Provisions in
the NBC 3. Cleaning of air or filtration
4. Air Supply
Concerning HVAC 4. Circulation of air
a. 5 cuft to 7-1/2 cuft of air per minute per
person (5-71/2 cuft/min/pers). In rooms
where smoking is not allowed

2.0
b.25 cuft to 40 cuft of air per minute per
person allowed in rooms where smoking
is permitted.

2.0 HVAC 2.0 HVAC

2.1.4 Methods of Cooling 3. Passing the air through coils 2.2 Refrigeration Cycle *Freon - refrigerant used for cooling.
Mechanical refrigeration is based upon the
containing the refrigerant itself; in
and De-humidifying alternate liquefying and evaporating of a volatile
this case the coils are called direct 1. Freon* is a gas at normal temperature liquid with a low boiling point usually Freon 12
2.1 General 2.1 General
expansion coils and pressure. It is first subjected to high (Dichlorodiflouromethane) or Freon 11
1. Passing the air through a spray of pressure in a compressor which raises its (Trichloromonoflouromethane) during which
2.2 Refrigeration 2.2 Refrigeration processes it respectively gives off and takes in
cold water 4. Passing the air through a boiling point and temperature.
Cycle Cycle heat. The desirable properties of Freon are: a)
combination of sprays and coils high heat of vaporization; b) moderate pressure
2. Passing the air through coils 2. At the same high pressure, the vapor is change for low to high temperature range; c)
2.3 Types of Air- 2.3 Types of Air-
Conditioning containing cold water Conditioning piped into condenser coils where it is non-toxic; d) incombustible; e) non-explosive;
cooled by water to a degree below its and f) non-corrosive.
Systems Systems
liquefaction point. It condenses into a
liquid state and still under high pressure,
2.4 Air-Conditioning 2.4 Air-Conditioning
passes to the evaporator.
Equipment Equipment
3. In the evaporator, the pressure is
2.5 Heating 2.5 Heating
relieved by the suction stroke of the
Systems Systems
compressor. The boiling point of the
liquid refrigerant drops and evaporation
2.6 Provisions in 2.6 Provisions in into a vapor takes place. The water
the NBC the NBC which surrounds the evaporator coils
Concerning HVAC Concerning HVAC gives up its heat in causing the
vaporization at low pressure, thus
reducing its temperature to the
temperature of the refrigerant. The cold
water can then be piped at this low
temperature to any desired point and
sprayed to cool the passing air. The
refrigerant is sucked back into the
compressor and the cycle recommences

2.0 HVAC 2.0 HVAC

2.3 Types of Air- 2. Split Type Air Conditioning
Conditioning Systems System
2.1 General 2.1 General
1. Central Systems
2.2 Refrigeration 2.2 Refrigeration
Cycle Cycle
All-Season Centralized Air
Conditioning System consists of
2.3 Types of Air- 2.3 Types of Air-
Conditioning the following: Conditioning
Systems Systems
a. A method of cooling,
a refrigeration plant
2.4 Air-Conditioning 2.4 Air-Conditioning
Equipment Equipment AHU
b. A source of heating
such as a boiler or
2.5 Heating furnace 2.5 Heating
Systems Systems FCU
c. An Air Handling Unit (FAN COIL
(AHU) equipped with UNIT)
2.6 Provisions in filters, pre-heater,
2.6 Provisions in COMP.
the NBC spray, cooling coils the NBC CONDENSER
Concerning HVAC and re-heater Concerning HVAC EVAPORATOR
ACCU
d. The air distributing (AIR CONDITIONING
equipment composed CONDENSING UNIT)
of ducts, fans and air ACCU
outlets

e. The necessary
manual or automatic
controls

1
 8/11/2016

2.0 HVAC 2.0 HVAC

3. Window Type Air Conditioning 2.4 Air-Conditioning 2. Condensers
System
Equipment
a) Air-cooled Condensers
2.1 General 2.1 General
used in unit and packaged-type air-
2.4.1 The Refrigeration conditioners up to 3 tons
2.2 Refrigeration 2.2 Refrigeration
Cycle Cycle Plant refrigeration.

2.3 Types of Air- 2.3 Types of Air- 1. Compressors b) Water-cooled Condensers

Conditioning Conditioning
Systems Systems a) Piston Type or Reciprocating Double-piped Condensers:
Compressors
2.4 Air-Conditioning 2.4 Air-Conditioning
Equipment Equipment for tonnages up to 100 tons

2.5 Heating 2.5 Heating b) Centrifugal Compressors

Systems Systems these are quieter, have fewer
vibration problems, require les s
2.6 Provisions in 2.6 Provisions in maintenance and with better
the NBC the NBC
operating control
Concerning HVAC Concerning HVAC

2.0 HVAC 2.0 HVAC

Shell and Tube Condensers: 3. Evaporators 2.4.2 Cooling and De- 2.4.4 Air Cleaning
humidifying Equipment
a) Shell and Tube Heat
2.1 General
Exchanger
2.1 General Equipment
1. Filters
2.2 Refrigera tion similar in operation to the shell and 2.2 Refrigeration
Cycle tube condenser. The refrigerant is Cycle
1. Water Sprays a) Dry Filters
expanded into a shell enclosing the consist of wire frames
2.3 Types of Air- tube through which the water flows. 2.3 Types of Air- 2. Cooling Coils enclosing felt, cotton or
Conditioning Conditioning sponge through which
the air is screened.
Systems
b) Direct Expansion Coils (coils Systems 2.4.3 Heating and
2.4 Air-Conditioning
containing the refrigerant itself) 2.4 Air-Conditioning Humidifying b) Viscous Filters
Equipment This may either be installed in the Equipment Equipment consist of metal
spray chamber so that the water deflecting plates or
2.5 Heating Evaporative Condenser: sprayed into the air comes into 2.5 Heating screens coated with
1. Tempering Coils viscous oil.
Systems contact with the cooling coils or the Systems
contains steam and are used
air itself comes into direct contact
2.6 Provisions in 2.6 Provisions in to heating the air ie., c) Water Sprays
with the cooling coils, as in the
the NBC the NBC preheaters and reheaters.
Concerning HVAC
window type unit Concerning HVAC d) Eliminator Plates
2. Water Heaters consist of corrugated
used for heating the water galvanized iron sheets
which will be used in the placed 1-1/8 apart
which deflect the air flow
spray chamber to add heat
about 30 deg catching
and humidity to the air the wet dust on the
surfaces

2.0 HVAC 2.0 HVAC

2.4.5 Air 2. Fans 3. Air Outlets
these are made for two locations:
Distribution
a) Centrifugal fans (radial fans) wall and ceiling.
2.1 General Equipment 2.1 General
these are intended for moving air at
2.2 Refrigeration 2.2 Refrigeration comparatively high pressures and a) Wall outlets include the
Cycle 1. Ducts Cycle are commonly used in duct systems. following:
are usually of Vaned outlets
2.3 Types of Air- galvanized sheet 2.3 Types of Air- b) Propeller or axial fans Perforated grills
Conditioning metal, or aluminum Conditioning commonly used for wall exhausts
Systems sheets, usually Systems b) Ceiling outlets include the
rectangular in following types:
2.4 Air-Conditioning 2.4 Air-Conditioning
Equipment section, depending Equipment Plaques
on the aspect Perforated panels
2.5 Heating ratio*, although 2.5 Heating Perforated ceilings
Systems circular ducts are Systems
also used for high
2.6 Provisions in velocity systems. 2.6 Provisions in
the NBC the NBC
Concerning HVAC *Aspect Ratio the ratio
Concerning HVAC
of the long side to short
side; not to exceed 5:1
although 4 or 3:1 is
preferred.

2
 8/11/2016

2.0 HVAC 2.0 HVAC

2.4.6 Control Equipment 2. Actuating or Operating 2.5 Heating Systems
Devices
2.1 General 1. Sensing Devices 2.1 General 2.5.1 Types of Heating
a) Dampers
a) Humidistat These control the flow of air and are Systems
2.2 Refrigeration 2.2 Refrigeration
Cycle or Hygrostat is a controller, sensitive in the form of louvers. Cycle TYPE OF HEATING HEATING METHOD METHOD OF
to the amount of humidity in the air. SYSTEM MEDIUM DEVICE OF AIR DISTRIBUTION
2.3 Types of Air- b) Control Valves 2.3 Types of Air- HANDLING
Conditioning These are valves with variable Conditioning
b) Thermostat Systems 1. Mechanical Air Furnace Ducts Registers
Systems orifices which are moved by motors
a controller which responds to Warm Air
2.4 Air-Conditioning changes in temperature. to present smaller or larger 2.4 Air-Conditioning Heating System
Equipment openings as directed by a Equipment 2. Steam Heating Steam Boiler Pipes Radiators
c) Pressure Regulators thermostat. System
2.5 Heating are instruments sensitive to changes 2.5 Heating
Systems c) Relays Systems 3. Hot Water Water Water Pipes Radiators
in pressure. They may control a Heating System Heater
single pressure or a differential These are devices that use electrical
2.6 Provisions in energy to amplify or convert the 2.6 Provisions in 4. Radiant Panel 1. Water Water Heater Pipes Ceiling or Floor
the NBC between two pressures. the NBC 2. Air Furnace Ducts Ceiling
power of a thermostat or other Heating System
Concerning HVAC Concerning HVAC 3. Electricity Elec Heater Wires Ceiling
controllers so that the resultant force
will be sufficient and adaptable to
operate a valve or damper.

2.0 HVAC 2.0 HVAC

2.5.2 Mechanical Warm Air 2.5.2 Steam Heating
Heating System System
2.1 General 2.1 General

2.2 Refrigeration 2.2 Refrigeration

Cycle Cycle
1. Air-Vent System (One-Pipe
2.3 Types of Air- 2.3 Types of Air- Gravity System)
Conditioning Conditioning
Systems Systems

2.4 Air-Conditioning 2.4 Air-Conditioning

Equipment Equipment

2.5 Heating 2.5 Heating

Systems Systems

2.6 Provisions in 2.6 Provisions in

the NBC the NBC
2. Vacuum System (Two-pipe
Concerning HVAC Concerning HVAC
Steam Heating System)

2.0 HVAC 2.0 HVAC

2.5.4 Hot Water Heating 2.5.5 Radiant Panel
System Heating System
2.1 General 2.1 General

2.2 Refrigeration 2.2 Refrigeration

Cycle Cycle

2.3 Types of Air- 1. One-Pipe Hot Water Heating 2.3 Types of Air-
Conditioning System Conditioning
Systems Systems

2.4 Air-Conditioning 2.4 Air-Conditioning

Equipment Equipment

2.5 Heating 2.5 Heating

Systems Systems

2.6 Provisions in 2.6 Provisions in

the NBC the NBC
Concerning HVAC Concerning HVAC

2. Two-Pipe Hot Water Heating

System

3
 8/11/2016

2.0 HVAC 2.0 HVAC

2.6 Provisions in the Capacity of Works, Project or Crane External Inspection
NBC Concerning HVAC Plant
The total horsepower of all engines,
Means a machine for lifting or lowering a
load and moving it horizontally, the
An inspection made on boiler during
operation.
2.1 General motors, turbines or other prime movers 2.1 General hoisting mechanism being an integral part
2.6.1 Definitions installed, whether in operation or not. of the machine. Guarded
2.2 Refrigeration 2.2 Refrigeration Shielded, fenced or otherwise protected
Cycle Compressor Cycle Duct by means of suitable enclosure guards,
Accidental Contact
Any inadvertent physical contact with A mechanical device for the purpose of A passageway made of sheet metal or covers or standard railings, so as to
2.3 Types of Air- 2.3 Types of Air- other suitable material not necessarily preclude the possibility of accidental
power transmission equipment, prime increasing the pressure upon the
Conditioning Conditioning leak tight, for conveying air or other gases contact or dangerous approach to
movers, machines or machine parts refrigerant.
Systems Systems at low pressure. persons or objects.
which could result from slipping, falling,
2.4 Air-Conditioning sliding, tripping or any other unplanned Condenser 2.4 Air-Conditioning
action or movement. A vessel or arrangement of pipes or Enclosed Internal Inspection
Equipment Equipment
tubing in which vaporized refrigerant is Means that the moving parts of a machine An inspection made when a boiler is shut
liquefied by the removal of heat. are so guarded that physical contact by down, with hand holes, manholes, or
2.5 Heating Air Conditioning 2.5 Heating
any part of the human body is precluded other openings opened or removed to
Systems The process of treating air so as to control Systems
Condemned Boiler or Unfired or prevented. This does not however permit inspection of the interior.
simultaneously its temperature, humidity,
prohibit the use of hinged, sliding or
2.6 Provisions in cleanliness and distribution to meet the Pressure Vessel 2.6 Provisions in
the NBC requirements of the conditioned space. A boiler or unfired pressure vessel that the NBC
otherwise removable doors or sections to Liquid Receiver
permit inspection, lubrication or proper A vessel permanently connected to a
Concerning HVAC has been inspected by the Building Concerning HVAC maintenance. system by inlet and outlet pipes for
Boiler Official and declared unsafe or
disqualified and power stamped or storage of a liquid refrigerant.
A closed vessel for heating water or for Evaporation
application of heat to generate steam or marked designating its rejection.
other vapor to be used externally or to
That part of the AC/refrigeration system in Locomotive Boiler
which liquid refrigerant is vaporized to A boiler mounted on a self-propelled track
itself.
produce refrigeration. locomotive used to furnish motivating
power for traveling on rails.

2.0 HVAC 2.0 HVAC

Low Pressure Heating Boiler Point of Operation Refrigerant 2.6.2 Boilers and Pressure
Vessels
A boiler operated at pressures not That part of a machine which performs an A substance which produces a
exceeding 1.05 kgs/sqm with steam or operation on the stock or material and/or refrigerating effect by its absorption of
2.1 General water temperature not exceeding 250F. that place or location where stock or 2.1 General heat while expanding or evaporating.
material is fed to the machine. A machine 1. Location of Boilers:
2.2 Refrigera tion Machine may have more than one point of 2.2 Refrigera tion Ton of Refrigeration
Cycle The driven unit of an equipment. operation. Cycle The useful refrigerating effect equal to a) Boilers may be located inside buildings
12,000 BTU/hour; 200 BTU/min. provided that the boiler room is of
2.3 Types of Air- Machine House Portable Boiler 2.3 Types of Air- reinforced concrete or masonry and that
Conditioning Conditioning
An enclosure for housing the hoisting An internally fired boiler which is self- Unfired Pressure Vessel the boiler room shall not be used for any
Systems contained, primarily intended for Systems
mechanism and power plant. A vessel in which pressure is obtained other purpose.
temporary location. from an external source or from an
2.4 Air-Conditioning 2.4 Air-Conditioning
Machine Parts indirect application of heat. b) In case the main building is not made
Equipment Prime Mover Equipment
Any or all moving parts of a machine. up of fire resistive materials, boilers shall
2.5 Heating
An engine or motor operated by steam,
2.5 Heating Ventilation be located outside the building at a
Mechanical Works Plant gas, air, electricity, liquid or gaseous fuels, Process of supplying or removing air by distance of not less than 3.00 m from the
Systems Systems
Includes steam plants, internal liquids in motion or other forms of energy natural or mechanical means to or from outside wall of the main building and the
combustion engine plants, hydraulic whose main function is to drive or any space. building housing the boiler shall be made
2.6 Provisions in 2.6 Provisions in
power plants, pumping plants, operate, either directly of indirectly, other up of fire resistive materials.
the NBC the NBC
refrigerating plants, air conditioning mechanical equipment.
Concerning HVAC Concerning HVAC
plants, mill shops, factories, foundries, c) No part of the boiler shall be closer
shipyards, etc. containing any mechanical Process Machine than one meter from any wall.
equipment, machinery or process, driven An equipment designed and operated for
by steam, internal or external combustion a specific purpose. d) Fire tube boilers shall be provided with
fuel, electricity, gas, air, water, heat, sufficient room for removal/replacement of
chemicals or other prime movers. tubes either thru the front or rear.

2.0 HVAC 2.0 HVAC

2. Smokestacks whether self 5. Two check valves shall be 10. Each boiler shall have a steam 13. Upon the completion of the
supporting or guyed, shall be of provided between any feed pump gauge, with a dial range of not less installation, the Building Official shall
conduct an inspection and test, after
sufficient capacity to handle fuel and the boiler in addition to the than 1-1/2 times and not more than which a certificate of operation for a
2.1 General 2.1 General
gases, shall be able to withstand a regular shut-off valve. twice the maximum allowable period not exceeding one year shall be
2.2 Refrigeration wind load of 175 km per hour and 2.2 Refrigeration working pressure. It may be issued upon payment of the required
Cycle shall rise at least 5 m above the 6. Where two or more boilers are Cycle connected to the steam space or to inspection fees.
eaves of any building within a radius connected in parallel, each steam the steam connection to the water
2.3 Types of Air- of 50 m. outlet shall be provided with a non- 2.3 Types of Air- column. 14. The Building Official shall notify the
Conditioning return valve and a shut-off valve. Conditioning owner in writing of the intended date of
Systems Systems the annual inspection at least 15 days in
3. Manufacturers/assemblers of 11. Whenever repairs/replacements
advance. However, the owner may
boilers/pressure vessels/pressurized 7. Boiler rooms shall have at least are made on fittings or appliances, request a postponement in writing of said
2.4 Air-Conditioning 2.4 Air-Conditioning
Equipment water heaters shall stamp each two separate exits. Equipment the work shall comply with the inspection and the Building Official shall
vessel on the front head or on any section on New Installation of the fix a date for inspection agreeable to both,
2.5 Heating other suitable location with the name 8. In no case shall the maximum 2.5 Heating Philippine Mechanical Engineering but not to exceed 30 days from the
Systems of the manufacturer, serial number, pressure of an old/existing boiler be Systems Code. intended date.
maximum allowable working increased to a greater pressure than
2.6 Provisions in pressure, heating surface in sqm would be allowed for a new boiler of 2.6 Provisions in 12. After a permit has been granted 15. The owner or user of a boiler shall
the NBC the NBC prepare the same for inspection by
and year of manufacture. same construction. to install a boiler/pressure
Concerning HVAC Concerning HVAC cooling it down blanking off all
vessel/pressurized water heater connections to adjacent boilers, removing
4. Boilers of more than 46 sqm 9. Each boiler shall have at least one upon payment of the installation all soot and ashes from tubes, heads,
heating surface shall each be safety valve. For boilers having more fees thereof, it shall be the duty of shell, furnace and combustion chamber.
provided with two means of feeding than 46 sqm pressure of water heating the Building Official to make periodic The owner shall assist the Building
water, one steam driven and one surface or a generating capacity inspection of the installation to Official by providing all labor and
exceeding 907 kg per hour, two (2) or equipment required during said
electrically driven, one pump and determine compliance with the
one injector. more safety valves shall be required. approved plans and specifications.
inspection.

4
 8/11/2016

2.0 HVAC 2.0 HVAC

2.6.3 Refrigeration and Air- 5. Where ducts pass thru walls, floors 8. Each refrigerating system shall be 12. Refrigerant piping crossing a
Conditioning or partitions, the space around the duct provided with a legible metal sign passageway in any building shall not be
shall be sealed with fire resistant permanently attached and easily less than 2.3 m above the floor.
2.1 General 1. The temperature and humidity of material equivalent to that of the wall, 2.1 General accessible, indicating thereon the
the air to be used for comfortable floor or partition, to prevent the name of manufacturer or installer, kind 13. In a refrigerating system containing
2.2 Refrigera tion 2.2 Refrigeration and total number of kgs of refrigerant more than 9 kgs, stop valves shall be
cooling shall be maintained at 68- passage of flame or smoke.
Cycle 74F Cycle installed in inlets and outlets of
contained in the system and field test
compressors, outlets of liquid receivers,
effective
movement temperature at 7.60
from 4.57 to an airMPM 6. When ducts or the outlets or inlets pressure applied.
2.3 Types of Air- 2.3 Types of Air- and in liquid and suction branch header.
Conditioning within the living zone. to them pass through fire walls, they Conditioning
Systems shall be provided with automatic fire Systems 9. In refrigerating plants of more than 14. Window type ACs shall be provided
dampers on both sides of the fire wall 45 kg refrigerant, masks and helmets with drain pipe or plastic tubing for
2.4 Air-Conditioning 2. Water from
condensers evaporators,
and other machinery shall through which they pass. 2.4 Air-Conditioning shall be used. These shall be kept in a discharging condensate water into a
Equipment Equipment suitable cabinet outside the machine suitable container.
be properly collected into a suitable 7. Fire doors and fire dampers shall room when not in use.
2.5 Heating water or drainage system. be arranged to close automatically and 2.5 Heating 15. Window type AC installed on ground
Systems remain tightly closed, upon the Systems 10. Not more than 136 kgs of floors of buildings shall not be less than
3. Ducts shall be constructed entirely operation of a fusible link or other refrigerant in approved containers shall 2.13 m from the ground.
2.6 Provisions in of non-combustible
steel, iron, aluminummaterials
or other such as approved heat actuated device, 2.6 Provisions in be stored in a machine room at any
the NBC located where readily affected by an the NBC given time. 16. Window type ACs shall be provided
Concerning HVAC approved
lining shallmaterials.
be used onOnly
the fire retardant
inside of abnormal rise of temperature in the Concerning HVAC with exhaust ducts if the exhaust is
duct. discharged into corridors/hallways/
11. Where ammonia is used, the arcades/sidewalks etc.
ducts. discharge may be into a tank of water,
which shall be used for no other 17. Window type ACs installed along
4. Access doors shall be provided at purpose except ammonia absorption. corridors/hallways/above the first floor
all automatic dampers, fire dampers, At least one gallon of water shall be shall not be less than 2.13 m above the
thermostats and other apparatus provided for every 0.4536 kg of floor level.
requiring service and inspection in the
duct system. ammonia in the system.

2.0 HVAC 2.0 HVAC

2.6.4 Piping 7. Piping carrying steam, hot water of hot
liquids shall not be embedded in concrete
walls or floors and shall be properly
1. Piping shall, as much as possible, run
2.1 General insulated to prevent accidental scalding to
parallel to building walls.
persons and to minimize heat loss.
2.2 Refrigera tion
Cycle 2. Grouped piping shall be supported on
8. Color coding of piping shall be as
racks, on either horizontal or vertical
follows:
planes.
2.3 Types of Air-
Conditioning a) Steam Division
3. Piping on racks shall have sufficient
Systems High Pressure- White
space for pipe or chain wrenches so that
Exhaust System Buff
any single line can be
2.4 Air-Conditioning b) Water Division
altered/repaired/replaced without
Equipment Fresh water, low pressure Blue
disturbing the rest. Fresh water, high pressure Blue
2.5 Heating Salt water piping Green
Systems 4. Piping 100mm in diameter and above
c) Oil Division
shall be flanged. Smaller sized pipes Delivery Brass or Bronze
may be screwed.
2.6 Provisions in Discharge Yellow
the NBC d) Pneumatic Division
5. Piping subjected to varying
Concerning HVAC All piping Gray
temperatures shall be provided with e) Gas Division
expansion joints.
All piping Black
6. Galvanized piping shall not be used for f) Fuel Oil Division
All piping Black
steam.
g) Refrigerating Division
Pipes Black
Fittings Black

2.0 HVAC 2.0 HVAC

5
 8/11/2016

2.0 HVAC
HEATING,
VENTILATION AND
refrigeration AIR-CONDITIONING

END