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HVAC Meaning (Heating, Ventilation & Air Conditioning)

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Q&A for Newbies

What HVAC stand for ?

Heating Ventilation & Air Conditioning

The employment of various technologies to control the temperature, humidity, and purity of the air in an enclosed environment is known as heating, ventilation, and air conditioning. Its purpose is to provide enough thermal comfort and indoor air quality.

Why HVAC is important ?

To keep a comfortable environment for people or electronics

HVAC helps to improve the air quality in a building, making it more suitable for human breathing and comfort. It lowers humidity, allowing inhabitants to enjoy a more pleasant environment. This is particularly useful in buildings or underground places with restricted ventilation.

How HVAC systems work ?

They cool by air passing over cold coils and heat by air over hot coils .

The most crucial thing to remember is that HVAC systems move air. In general, there is a system in place to transport warm air elsewhere, either into or out of the house. The heat is captured or created by the air conditioner, heat pump, and furnace in a home, and then moved by the blower and ductwork.

Are HVAC systems energy efficient ?

HVAC consume 40% of building energy, there are many ways to save.

Replacement of heating and cooling equipment with greater efficiency equipment can cut energy use by 50% for electric heating and cooling systems and 10% for gas furnace heating systems, depending on your region.

Where are HVAC systems located ?

In some areas, the HVAC system is frequently installed outside the home or on the roof. A commercial system, on the other hand, may be installed in the swamp cooler or on the roof of a structure. The latter is a huge space saver, as well as providing superior noise control and simpler maintenance access.

Will HVAC systems spread covid ?

Yes and no if well protected by HEPA filters.

Yes, most people now agree that the coronavirus, also known as COVID-19, is airborne. Small virus particles are light enough to be recirculated through the system, which is a worry when it comes to circulating air. As a result, airborne viruses have a direct impact on HVAC and air conditioning systems (HVAC)

Can HVAC make you sick ?

No, except if you do not maintain it well and clean the filters.

HVAC (heating, ventilation, and air conditioning) systems are excellent for keeping a room at a comfortable temperature. You are not ill because of your HVAC system! Adjusting your home environment to prevent airborne viruses, on the other hand, will reduce your chances of being unwell.

Which HVAC system is Best ?

Carrier, Trane, York, Rheem, Lennox, LG, Samsung, Stultz

Are HVAC purifiers worth it ?

Yes, make sure you get proper ones with HEPA filters and for the room size.

It surely is if breathing clean air is a priority for you. The installation of an air purifier should be a stronger consideration for allergy and asthma sufferers, as well as individuals with chronic respiratory difficulties.

When should HVAC be replaced ?

Whenever it starts breaking down often or new technology with more efficiency.

Homeowners should update their HVAC system every 10 to 15 years, according to the manufacturer. Modern air conditioners are long-lasting, but depending on how often you use and repair them, their principal components will begin to deteriorate after around ten years.

Which HVAC system should I buy ?

Depending on your application, We can consult on this issue.

What's the difference between Residential and industrial HVAC?

Residential are much smaller and located indoors, while Industrial and commercial are located outside in most f the applications.

The distinction between the residential and commercial markets is one of the most important disparities in the HVAC industry. Commercial HVAC deals with the heating and cooling systems of corporate and industrial buildings, whereas residential HVAC deals with the heating and cooling systems of houses and small enterprises.

International HVAC & M&E Services

HVAC consultant, HVAC business consulting, HVAC business coaching, HVAC consulting firm, HVAC design consultant, HVAC Consulting companies, HVAC consulting services, Residential HVAC consultant

HVAC Basic Training - How does HVAC work in different applications

operating theater

HVAC in operation Theater

Operating Theater HVAC Design Criteria

An operating theater is a facility within a hospital where surgical operations are carried out in an aseptic environment. Historically, the term "operating theatre" referred to a non-sterile, tiered theater or amphitheater in which students and other spectators could watch surgeons perform surgery.

  • Air supply by HEPA filter diffusers blowing air away from Patient

  • Downward Laminar Air Flow

  • Minimum of 20 ACH (Air Change per Hour)

  • Minimum 20% Fresh Air

  • Positive pressure to surrounding rooms

  • Air Velocity between 0.15 to 0.25 m/s

  • Temperature between 20°C to 24°C

  • Humidity between 30 to 60 RH

  • Personnel to wear full body Suits

  • Walls & Floors, Hard surfaces with non porous materials

  • I can be consulted on this and help you achieve your goals Remotely.

freelance picture

HVAC career as a Freelancer

How to become an Independent HVAC Contractor & find Technical Freelance work

Freelance freelancer, or freelance worker, are terms commonly used for a person who is self-employed and not necessarily committed to a particular employer ...

If you want to become an independent HVAC contractor, you will need to find technical freelance work. You can find this work by searching online job boards or by contacting HVAC companies directly. Once you have found some potential work, you will need to submit a proposal to the company. In your proposal, you should include your qualifications, your price, and your availability. If the company is interested in your proposal, they will contact you to discuss further details.

  • Deep Knowledge in your field is POWER. Keep Learning

  • Make a Technical Blog to display your knowledge, do not have to be deeply technical, these days it is better than a CV. Show your skills.

  • Make a video Channel and display with Graphics your tech skills. Short videos.

  • Direct contact companies by email & preferably Medium sized or small companies to reach the decision makers.

  • Filter job boards to give you only contract work.

  • Do send to permanent offers and state you are only interested in contracting, it's all about negotiating and convincing for a win-win situation. Companies can save with contractors.

  • Build a network on social media, target decision makers.

  • Have discussions on groups related to your business and answer some people's tech questions.

  • Offer remote work and be prepared to discuss & offer what can be done remotely and what cannot.

  • Use automated computer skills such as scripting to help you achieve your goals.

  • On your free time, keep up to date in your field.

  • I can be consulted on this and help you achieve your goals Remotely.


HVAC energy saving

HVAC Energy Saving

HVAC systems are responsible for a large portion of the energy used in commercial and residential buildings. As a result, there is a great deal of opportunity for energy savings through proper HVAC system design, operation, and maintenance. The first step in saving energy with your HVAC system is to ensure that it is sized properly for the building it is serving. An oversized system will cycle on and off more frequently, leading to increased energy use and wear and tear on the system. Once you have a properly sized system, there are a number of things you can do to ensure it is operating as efficiently as possible. For example, regular maintenance is important to keep the system clean and operating at peak efficiency. Additionally, making sure the system is properly insulated and sealed will help to minimize energy losses. There are also a number of innovative technologies that can be used to further improve the efficiency of HVAC systems. For example, variable speed drives can be used to better control the flow of air and optimize system operation. Additionally, using solar panels to preheat air before it enters the HVAC system can lead to significant energy savings.

  • Utilise Variable Frequency drives on Air, Refrigerant and Hydronic systems

  • Use Free Cooling where possible

  • Ice Storage during off Peak

  • Use heat Recovery Wheels

  • Green roofs

  • External reflective paint

  • Double or triple Glazing

  • Use Parapetes

  • Co-generation

  • Use Artificial Intelligence to control your smart building

  • Reflective architecture

  • Retrofit Old Systems

  • Invest in New systems Energy Star

  • Increase the Insulation of your space

  • Use duct sealing

  • Preserve your Airflow

  • Make use of Curtains and Blinds

  • Perform Regular Maintenance

  • Clean and Change Air Filters

  • Trim Plants and Grass around external condensing Units

  • Design proper duct systems, Round when Possible

  • Place External Units in Shades when Possible

  • Tune up Your HVAC Systems

  • Install Programmable Thermostats

  • Use smart Sensors and BMS systems

  • Smart Maintenance and coordinated cleaning Hours, to save on Lighting

  • Recommend and use LED lighting

  • Use Occupancy Sensors

  • Install Power Management Software

  • Harvest Daylight

  • Adjust Ventilation

  • Reuse Valuable HVAC air - transfer

  • Power down Electronics

  • Savings on Electrical Systems (per request)

  • I can be consulted on this and help you achieve your goals Remotely.

hvac ductwork

HVAC Design

HVAC Design & Implementation

Heating, ventilation, and air conditioning (HVAC) is the technology of indoor and vehicular environmental comfort. Its goal is to provide thermal comfort and acceptable indoor air quality. HVAC system design is a sub-discipline of mechanical engineering, based on the principles of thermodynamics, fluid mechanics and heat transfer


  • Obtain the project architectural drawings after consulting with the architect for space allowance and proper coordination.

  • Do Cooling & Heating load calculations with the help of professional software or excel sheet.

  • Zone building areas.

  • Do Mechanical equipment selections.

  • Sketch single line design Duct & equipment Drawings.

  • Do full mechanical Drawings.

  • Final Review and Coordination with other services, Fire fighting, Plumbing, Electrical, BMS.

  • Do shop Drawings.

  • Obtain local authority approvals where they apply.

  • Do equipment Schedules & sequence of operation & controls.

  • Order equipment.

  • Selection of construction contractors.

  • Start construction execution.

  • Daily coordination on site and with contractors.

  • Prepare equipment and calculation documentations.

  • Site testing & commissioning.

  • Final Acceptance.

  • Selection of operation & maintenance contractors.

  • Hand over to client.

  • Train and handover to Operations and Maintenance team.


  • I can be consulted on this and help you achieve your goals Remotely.

nuclear plant

HVAC in Nuclear Plants

HVAC and Ventilation systems of Nuclear Power Plants

A nuclear power plant (sometimes abbreviated as NPP) is a thermal power station in which the heat source is a nuclear reactor.

Nuclear power plants require specialised HVAC and ventilation systems to ensure the safety of workers and the public. The systems must be able to maintain the temperature and humidity at safe levels, as well as providing adequate ventilation. The HVAC systems at nuclear power plants are designed to keep the temperature and humidity at safe levels for both workers and the public. The systems must be able to maintain the temperature and humidity at safe levels, as well as providing adequate ventilation. The ventilation systems at nuclear power plants are designed to remove any radioactive contaminants from the air. The systems must be able to operate continuously and be able to filter out any radioactive particles. The HVAC and ventilation systems at nuclear power plants are essential for the safety of everyone involved. Without these systems, the risk of exposure to radiation would be much higher.

  • The General purpose of the HVAC in nuclear plants is to maintain air purity, Temperature, humidity and airflow between zones

  • The radiation exposure level arising from a plant shall be kept as low as possible by the ventilation system

  • Nuclear power plant shall be divided into different zones of different class pressures and Air changes per hour

  • All rooms & halls shall be airtight

  • The HVAC cooling systems are to cool equipment & personnel

  • The main rooms of the nuclear plants are: Process plants, caves, cells, labs, decontamination centres, airlocks, change rooms, waste stores & glovebox

  • To avoid back flow, a minimum flow of 0.5 M/s between zone openings

  • Zone classes are from white areas the least contaminated, Green, Amber, Red the most contaminated

  • Difference in pressures to be maintained between zones from the non-controlled white class areas to the most controlled Red class areas as the most Negative

  • Exhaust ducts shall be sealed airtight and serve the controlled areas, filtered with HEPA filters and exhausted at high velocities

  • Burning poisonous & hazardous gases to be extracted by independent exhaust stacks

  • High rate of Fresh air for decontamination to be filtered with HEPA filters in case of accident contamination on site

  • Pre heaters to be installed before Fresh air HEPA filters to avoid freezing and fire fighting sensors to be installed to detect fire to the filters with means of extinguishing the fire

  • In case of fire all stairwells and corridor shall be over pressurised as an escape route

  • Non Flammable material shall be used where possible

  • Auto Smoke exhaust to be served by an independent exhaust system with the exception of manual exhaust in controlled areas, to avoid contamination

  • Zone Classes and air Changes per hour ACH as follows

  • Corridors ACH 1-2 Green Class

  • Controlled areas medium Hazard 2 ACH Green Class

  • Airlocks/ Change rooms 4-5 ACH Amber class

  • Controlled areas High Hazard 5-10 ACH Green Class

  • Maintenance High risk 10 ACH Amber

  • Goveboxes, Caves, Cells 10-30 ACH RED

  • BMS (building management systems) to control, HVAC equipment, airflows, pressures,Temperatures, radio active ect...

  • For more information or contract ,contact the Publisher

  • I can be consulted on this and help you achieve your goals Remotely.

medical pills

HVAC in Pharmaceuticals

HVAC fundamental design for Pharmaceutical production

The pharmaceutical industry discovers, develops, produces, and markets drugs or pharmaceutical drugs for use as medications.

The HVAC system for a pharmaceutical production facility must be designed to maintain a clean and controlled environment while providing the appropriate levels of temperature and humidity. The system must also be designed to meet the specific needs of the production process. The first step in designing an HVAC system is to determine the required levels of cleanliness and control. The level of cleanliness required will depend on the type of product being produced. The level of control required will depend on the production process and the sensitivity of the ingredients. Once the required levels of cleanliness and control have been determined, the next step is to select the appropriate air handling unit. The air handling unit must be able to provide the required levels of filtration, humidity control, and temperature control. The air handling unit must be sized to meet the needs of the production process. The unit must be able to deliver the required amount of air to the production area and exhaust the contaminated air. The air handling unit must be equipped with the appropriate type of filters. The type of filter will depend on the level of cleanliness required. The most commonly used filter is the HEPA filter. The air handling unit must be equipped with the appropriate type of humidifier.

  • Hvac can control air born dust, mirco organism, skin flakes, infiltration & hair.

  • Hvac maintains positive air pressure in the fabrication laboratory (clean room).

  • Hvac maintains more positive pressure than the adjoining less critical rooms.

  • Hvac Maintains 50% Relative humidity and require clean RM temperature.

  • Fabrication lab walls should be all sealed from penetrations, electrical cables, ducts etc...

  • Cooling load is from Lighting, equipment, personnel & partitions.

  • Air shower rooms at the entrance of the clean rooms.

  • Ducts sealed with silicon, no acoustic lining & rubber gaskets.

  • Hard surfaces with non porous materials, walls, floors etc...

  • Clean rooms are classified between Class 100 to class 100,000 in Pharma.

  • Examples: Tableting class 100k, oral product class 10k, Injectable products class 100.

  • Critical areas not less than class 100. Maybe even less standards now with Covid-19.

  • Airflow to be laminar at 90 FPM and pressurisation of 0.05"WG.

  • Manufacturing labs , 55 pascals + positive pressurisation.

  • Unidirectional airflow, so no turbulence occurs.

  • HEPA filters to be used at 99.97% & down to 0.3 microns.

  • When de-fumigation is done, 100% Fresh air and the equivalent exhaust air to clear the formaldehyde.

  • Minimum of 20 ACH (air change per hour).

  • Recirculating air due to the high volume of air from the ACH.

  • AHU sections but not limited to: Pre-filters, Pre Heat coil, cooling coil, fan, humidifier, air monitoring, reheat coil, return fan, , relief damper, return damper, Fresh air damper,

  • BMS , DDC system to monitor, all ahu parameters, pressurisation, filters, etc...

  • For more details please contact the publisher

  • I can be consulted on this and help you achieve your goals Remotely.

subway station

HVAC in subways

Hvac for Subway Stations

Subway, a term for underground rapid transit rail systems ·

The hvac system for a subway station must be able to provide ventilation for the station as well as for the tunnels. The system must also be able to cool the station in the summer and heat it in the winter.

  • Subways are treated as a moving heat source in tunnels and from station to station, heat source (breaks , engines and condensers)

  • Subways stations are in some cases mechanically cooled

  • AHUs are to be equipped with HEPA filtration

  • Train separation compartment are recommend to eliminate draft in stations

  • Subway stations need to be ventilated with fresh air

  • Subway tunnels are just ventilated with fresh air supply & exhaust

  • Smoke extraction code overrides for fans and duct sizing in case of fire emergency

  • Escape routes to be over pressurised in case of emergency

  • Due to the Piston effect of a moving subway vent shafts connected to louvers are at the entry & exit of each tunnel with baffles

  • Transfer Fans are utilised to push fresh air into the tunnels

  • UPE (under platform exhaust) & OTE (overt rack exhaust) are in use

  • Station Filtration units are recommended with HEPA filters

  • BMS includes but not limited to (CO2, airflow, temperatures, humidity, AHUs, filters, fans, smoke sensors, pressure, compressors)

  • For contracts or further details please contact the publisher

  • I can be consulted on this and help you achieve your goals Remotely.


HVAC Design for cleanrooms

HVAC Cleanrooms Design

A cleanroom or clean room is a facility ordinarily utilized as a part of specialized industrial production or scientific research, including the manufacture of pharmaceutical items, integrated circuits, LCD, OLED and microLED displays.

HVAC design for cleanrooms must provide for the special needs of these types of environments. Cleanrooms are typically used in manufacturing and pharmaceutical settings where the control of air contamination is critical. The HVAC system must be designed to maintain a clean environment by providing filtered air, controlling temperature and humidity, and preventing airborne contaminants from entering the room.

  • Cleanroom is a facility as part of a scientific research,Laboratories, Disease Control, Industrial Production, Operation Theaters, Research, Pharmaceutical, Integrated Circuits, Semiconductor Fabs, Space Station assembly, Micro Assembly, CRT, LCD, OLED, Micro led, microfilm etc...

  • Cleanrooms are design to maintain extremely low level particulates per air volume.

  • Ambient Air contains around 35 million particles per cubic meter Ranging from 0.1 Um - 5 Um (micro meter).

  • Cleanrooms should be pressurised at around 0.2 H2O - (20 Pascals) and above.

  • Cleanrooms standards depending on the application range from ISO1 to ISO9, (class1 to class 100,000)

  • Cleanrooms ACH (air change per hour) depends on the application and vary in the range of 360 to 750 ACH.

  • Supply air to clean rooms are laminar flow (piston Effect) from ceiling level supply to low level side wall Exhaust &/or Return.

  • Diffusers are to supply air in uni-directional form, not to cause any turbulence.

  • Clean rooms utilise HEPA or ULPA filters (high/ultra high efficiency particulate air).

  • Cleanrooms walls, ceiling, floor, tables etc... are to be of smooth surfaces not to collect dust particles.

  • Supply Air is by FFU (filter fan units), AHUs, Fresh Air Units, Exhaust/Return fans.

  • Air locks/Air showers are entry rooms to clean rooms and should be maintained at lower pressure than the clean rooms.

  • BMS (building Management System) to control/sense airflows, humidity level, Temperature, FFUs, Fans, filters, AHUs, Fresh air volume, supply temperature etc... according to application in use.

  • For more specific design details or contract propositions please contact the publisher.

  • I can be consulted on this and help you achieve your goals Remotely.

hotel room

HVAC in hotels

HVAC For Hotels

A hotel is an establishment that provides paid lodging on a short-term basis.

The HVAC system for a hotel must be designed to provide comfortable indoor temperatures and air quality for guests and employees while also being energy efficient. The size and layout of the hotel, as well as the climate, will dictate the type of system that is best suited for the property. A well-designed HVAC system will provide uniform temperatures throughout the hotel, while also accounting for areas that may need to be cooled or heated more or less than others. The system should also be designed to provide fresh air to all areas of the hotel and to exhaust stale air from bathrooms and other high-use areas.

  • Hotels are separated into different zones, rooms, kitchen, lobby, dining area, laundry, offices, indoor pool, garage, restaurants.

  • Hotels HVAC consume between 40-50% of total energy.

  • Cooling / heating loads to be calculated at peak hours with the help of computer programs analysis.

  • Proper walls and windows heat transfer mediums to be used (double glazings, reflective films, well insulated walls)

  • Hotels are served by chillers (air cooled or water cooled).

  • Fresh air units are on the roof or in mechanical floors and they supply each room FCU (fan coil units) via shafts and corridors ducts.

  • All other zones are served by AHU's at different locations, rooftops, mechanical rooms, ground floor. Served preferably by dedicated Fresh air units.

  • Recommend HEPA filters on recirculated HVAC units.

  • Some DX systems might be in use at certain specific areas Ex: (IT room).

  • Heat recovery units to be used at Fresh air units from exhaust and toilet exhaust.

  • Stairwells are to be pressurised against smoke for escape routes.

  • Garage areas are to be ventilated and exhaust systems in place.

  • High rise elevators to be pressurised against smoke.

  • VAV systems are to be used in certain areas.

  • Latest BMS technology to be used for proper control and energy savings.

  • Special care of supply air to indoor pool areas due to high humidity loads.

  • Independent Kitchen exhaust system.

  • Independent Smoke exhaust system.

  • Independent Laundry exhaust system.

  • Fire dampers in duct at walls and rated per wall / floor resistance.

  • Transfer heat duct recovery to be utilised where permissible to save energy.

  • Solar heat collectors to be used where feasible and permissible.

  • Green roofs to be used where permissible.

  • For more details please contact myself

  • I can be consulted on this and help you achieve your goals Remotely.


HVAC on Ships

HVAC for Ships (cruise, cargo & military, offshore)

A ship is a large watercraft that travels the world's oceans and other sufficiently deep waterways, carrying goods or passengers.

The HVAC system on a ship is a critical part of the vessel's overall design. The system must be able to maintain comfortable temperatures for the crew and passengers while also dealing with the unique challenges posed by a maritime environment. Some of the key considerations in designing an HVAC system for a ship include:

1. The effects of waves and weather on the ship's HVAC system.

2. The need for the system to be able to cope with the ship's motion.

3. The need to maintain a comfortable environment in a variety of different climates.

4. The challenges posed by salt water and humidity.

5. The need to deal with the ship's engine noise and vibration.

6. The limited space available on a ship for HVAC equipment.

7. The need for the system to be easy to maintain and repair.

  • Hvac is the second most energy consumption on ships, special care with sophisticated control systems are to be used to save energy.

  • Fire, smoke and corrosion control are of highest importance

  • Heat loads: solar , sensible, latent, occupants, lighting, wall/roof gains, electrical equipment, hot piping, Fresh air, infiltration, motors. (ventilation, solar and skins conduction varies to the area of ship operation) Maximum to be allowed.

  • HVAC can be DX, usually for smaller areas and chilled water for large halls but not the rule.

  • Condenser units use sea water with heat exchangers and sometimes air where permissible.

  • Cabins HVAC, FCU units are also used for independent control, some cabins are pre manufactured and then slide in one by one during construction.

  • Diffusers: special attention to diffusers due to low ceilings, not to cause drafts.

  • VAV systems are used for energy control and sometimes dual duct systems are used.

  • AHU sections: Filters, HEPA for crowded spaces (atrium, cinema, dining areas etc...) heat recovery wheels, coils, (heating , cooling) humidifier, sound attenuation. Plus two condensate drains due to ship movement.

  • Ductwork: preferably round due to tight spaces as well protected against fire, attenuation lining.

  • BMS: of highest quality and most advanced systems to save energy and control well the humidity level.

  • Fresh air: to be adjusted with amount of CO2 detection in large areas, atrium, dining, cinema etc...

  • Spares parts: always to be ready on board as the ship is far from land. ex: oil, refrigerant, filters.

  • Coils: copper tubes, fins also exposy coated.

  • Chilled beams are also used to save on energy and space.

  • For more details or consultation please contact.


HVAC plane design

HVAC Systems in Airplanes

An airplane or aeroplane (informally plane) is a fixed-wing aircraft that is propelled forward by thrust from a jet engine, propeller, or rocket engine.

HVAC systems are critical for maintaining comfortable temperatures and good air quality for passengers and crew on board an aircraft. The systems are designed to maintain a comfortable cabin environment while the aircraft is at cruising altitude and can also provide fresh air and ventilation when the aircraft is on the ground. There are three main types of HVAC systems used on aircraft:

1. Recirculating: This type of system recirculates cabin air and filters it to remove contaminants.

2. 100% Fresh Air: This type of system constantly brings fresh air into the cabin from outside the aircraft.

3. Mixed Mode: This type of system uses a combination of recirculating and fresh air to provide the best air quality and temperature control. HVAC systems are typically controlled by a thermostat and include sensors to monitor temperature, humidity, and air quality. The systems also include filters to remove contaminants from the air.

  • The air is bled off the engines at very high temperatures due to compression 400 F into 2 air packs in the wings close to cabin’s body.

  • The air is cooled by RAM air into heat exchangers from outside air at -65 F.

  • 50% of the air is recirculated & 50% is Fresh air mixed, then filtered with HEPA (high Efficiency Particulate Air) filters.

  • Minimum requirement is 20 CFM (cubic feet / Minute) per person outside fresh air.

  • Minimum 15 Air change per hour at the cabin, this means changing the air volume of the cabin 15 times / hour.

  • The Supply at air nozzles velocity at 500 fpm (foot / Minute), these are the diffusers above your seats.

  • The Return air is at each row under the windows, so it keeps contaminants / viruses separate per row.

  • The Air condition controllers at the packs to control the supply temperature with bypass air valves help and hot air mixture.

  • The air is supplied to the overhead mixer units, also supplied by ground HVAC unit in tarmac taxi mode, when the plane is parked at airports.

  • In the case of failure of the HVAC packs, emergency ram flaps are open up by the captain at lower altitudes.

  • The cabin is normally divided into 3 zones, cockpit and 2 divisions in the passengers cabin area.

  • We can be consulted further on this and help you achieve your HVAC Goals or solve your HVAC issues.

  • We also do Promotion for HVAC related companies & their products.


HVAC in Datacenters

HVAC + M&E Items in DATA-CENTERS (keep it Simple)

A data center (American English) or data centre (British English)is a building, a dedicated space within a building, or a group of buildings used to house computer systems and associated components, such as telecommunications and storage systems.

HVAC systems play a vital role in data centers by providing the necessary cooling to keep equipment operating at optimal levels. By circulating cool air and removing heat, HVAC systems help protect against equipment failure and downtime. In addition, HVAC systems can also help improve air quality within data centers, reducing the risk of contamination and preventing the spread of airborne diseases.

  • Architectural - 4+ meters height slab to slab, raised floor with perforated tiles, False Ceiling (optional), loop corridor, cold and hot aisles, shafts if necessary, 1000 kg weight per M2, pressurisation.

  • Redundancy - N+1, N+2 or 2N, Tier 1,2,3 or 4 & 5

  • Lighting - uniform 500 lux, emergency lighting, fire alarm lighting, skylights

  • Fire fighting - clean agent extinguishing gas, water mist, alarms, exhaust

  • BMS- connected to HVAC, Intruder, lighting, heating, fire fighting, NOC (network operation center)

  • HVAC - Chillers, Dx systems, AHU, FCU, Fans, Fresh air Units, Free cooling, heat recovery

  • Electrical - Generators, 2 Electrical feeds to site, UPS, Batteries, DC power if required to some IT, ATS, power meters. Solar Panels + accessories, double equipment feeds A+B, Locked distribution Panels, 24Hrs+ Diesel Tank, solar panels

  • Security - Intruder alarms, CCTV, access cards, finger/palm prints, sirens, smoke & gas evacuation, Night Guard with Dog, emergency medical kits.

  • IOT - wherever required with latest IOT tech.

  • Drones - for facility management.

  • AI - energy saving systems from past collected data + preventive/corrective maintenance alerts.

  • Main Sensors - High temp, low temp, electric feeds, airflow, DC room temp sensors, Diesel level sensor

  • I can be consulted on this and help you achieve your goals Remotely.

HVDC room

HVAC deign for HVDC

HVAC approach for HVDC application.

A high-voltage, direct current (HVDC) electric power transmission system uses direct current (DC) for the bulk transmission of electrical power

  • HVDC (high voltage DC supply) is mainly used for long distances to minimise power loss.

  • The converter/rectifier hall is 1 big faradays cage designed hall with no entry to personnel during normal operations.

  • All indoor M&E equipment must be grounded.

  • Only ventilation is required except for high temp regions like the gulf.

  • N+2 configuration for redundancy.

  • AHU sections. Heating coil, humidifier, pre-filter + bag filter.

  • 100 % fresh air with 30 Pascals pressurisation and with gravity release dampers at upper levels of the converter hall.

  • Interior design Maximum 48 C minimum 5 C, maximum supply temp. 40c and minimum at 10c, maximum Relative humidity 60% and minimum 30%

  • Heat losses on Average 300 KW, including Process piping.

  • 500 Lux uniform Lighting.

  • For security, entrance doors are interlocked for power shutdown in case of fire.

  • Fire fighting, manual extinguishers at entry and automatic interior extinguishing on the interior for the controls room.

  • BMS, all sensors High Temp & Low temp, high & low humidity etc... to connect to Controls room.

  • I can be consulted on this and help you achieve your goals Remotely.

medical equipment

HVAC design for Healthcare

HVAC for healthcare facilities

Health care is the maintenance or improvement of health via the prevention, diagnosis, treatment, recovery, or cure of disease, illness, injury, and other physical.

Healthcare facilities have a wide range of heating, ventilation, and air conditioning (HVAC) needs. In general, these facilities require HVAC systems that are highly energy efficient and have good indoor air quality control. The most common type of HVAC system in healthcare facilities is the central air system. This system consists of a central unit that provides heating and cooling for the entire facility. The central unit is usually located in a mechanical room and is connected to the facility’s ductwork. Another type of HVAC system that is often used in healthcare facilities is the split system. This system consists of two units: an outdoor unit that provides heating and cooling, and an indoor unit that provides ventilation. The indoor unit is usually located in a mechanical room, while the outdoor unit is located outside of the facility. Healthcare facilities also often use packaged HVAC units. These units are self-contained and provide heating, cooling, and ventilation in one unit. Packaged units are typically located on the roof of the facility. In order to ensure that healthcare facilities have the right HVAC system for their needs.

  • Most rooms in Healthcare facilities are either Positive or negative pressure, 15% higher on exhaust or Fresh air to cause the required pressurisation. Positive for non sick and negative for sick patients.

  • Most rooms are at 100% Fresh air.

  • 12 ACH (air change per hour) is good for diluting the air and not high enough to cause turbulence.

  • Every patient room to have an anteroom (an airlock).

  • Pressurisation should not be less than 2.5 Pascals.

  • HEPA filters at 99.97%.

  • VAV boxes are not recommended.

  • Room surfaces shall smooth and free of fissures.

  • Doors to be self closing.

  • Positive rooms can be under 1 zone served by 1 AHU and vice versa.

  • Patients rooms can be under Horizontal or vertical air flow.

  • 5 types of filtration, Straining, Impingement, interception, Diffusion & Electrostatic.

  • Operation Theaters shall be clean rooms with down flow air supply from HEPA filters.

  • Kitchen (2000 fpm), laundry and toilet exhausts shall be all separate exhaust systems.

  • UVGI- Ultraviolet Germicidal Irradiation in AHU units.

  • Temperatures around 20 and RH 50%.

  • Noise Criteria 35 NC level.

  • All M&E equipment shall be on Backup power (Generator, UPS where permissible).

  • BMS - mainly airflow sensors and differential pressures.

  • I can be consulted on this and help you achieve your goals Remotely.

semiconductor plant

HVAC design for Semiconductor FAB

HVAC for Semiconductor Fabrication & Exhaust

Semiconductor device fabrication is the process used to manufacture semiconductor devices, typically the metal–oxide–semiconductor (MOS) devices used in the integrated circuit (IC) chips such as modern computer processors, microcontrollers, and memory chips such as NAND flash and DRAM that are present in everyday electrical and electronic devices.

The HVAC system for a semiconductor fabrication facility is a critical part of the process, as it provides the cleanroom environment necessary for the semiconductor manufacturing process. The HVAC system must maintain a clean and dust-free environment, as well as control temperature and humidity levels. The system must also be designed to meet the specific needs of the semiconductor manufacturing process.

  1. The main rooms in a Fab is cleanrooms, FABS & Sub-FABS

  2. Cleanrooms are served by the following equipment

    • RAH (return air handler)-(heater, humidifier, Fans, filters, cooling coils)

    • FFU (fan filtered Units) - High efficiency particulate air - filters

    • MUA (make up air unit) -(heater, humidifier, Fans, filters, cooling coils)

    • Exhaust - See below

  3. Cleanrooms are positive pressurised, to keep out duct particles.

  4. HEPA or ULPA filters are used in the FFU

  5. Pre-filters and bag filters in AHU's

  6. ISO class 5 with above 100 ACH (air change per Hour)

  7. Unidirectional airflow from ceiling to low room level return

  8. Pressurisation of 5 to 20 Pa. (0.02” to 0.08” w. g.)

  9. Room surfaces shall smooth and free of fissures.

  10. Airlocks with air showers at the entry points

  11. Doors to be self closing.

  12. Raised floors

  13. Exhaust from semiconductor Fabrication

    • VOC (Volatile Organic Compound)

    • ACID

    • Ammonia

    • General Exhaust

    • Agua Regia Exhaust -rare

    • High ACID

    • Silane

    • General Heat Exhaust

    • Pyrophoric

    • PFC

    • EPI

    • Hydrogen

    • Emergency release

    • Chemical Storage and waste tanks vents

    • Never mix Ammonia with acid

    • Sloped ducts with drains, sometimes heated ducts @ 400 Celcius

    • Round ducts

    • High Velocity - 3000 FPM (foot per minute)

  14. POU (Point of use) filtration at the process units

  15. Scrubbers are main items in exhaust

    • neutralising PH solutions for ACID or ammonia

    • chemical dosing

    • granular

    • chemical absorption

    • drainage

    • burners

    • sometimes in series

    • Electrostatic Precipitator

For Design details contact myself or exhaust specialist & partner -

  • I can be consulted on this and help you achieve your goals Remotely.

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