HVAC Duct Sizing Calculator

Use this calculator to calculate HVAC duct sizes using equal...

Solar Air Conditioning

Solar energy has always been attractive to the building serv...

How to Size U-Trap - AS/NZS 3666.1

Why is u-trap important and how to size an u-trap for air ha...

Wet bulb depression efficiency-evaporati...

For those who have been to Malaysia, the first thing you eve...

Generator Room Ventilations

Use this generator room ventilation calculator to estimate t...

Room Noise Predictor From AHU to Diffuse...

Use this room noise predictor to estimate the expected noise...

AS 1668.2 Kitchen Exhaust Calculator

Use this AS 1668.2 kitchen exhaust calculator to estimate mi...

Comparison with P, PI & PID

The Physiological Basis for Air Conditio...

Seasonal extremes of heat and cold are often outside the ran...

Carpark exhaust control

Small in Window Air Conditioner Units In...

As its name suggests, unitary window air conditioners consis...

Cooling Coil Bypass Factor Calculator

Use this calculator to estimate cooling coil bypass factor u...

How to verify the percentage of outside ...

Use this outside air percentage calculator to estimate how m...

Indirect Evaporative Cooling-The Univers...

In 2011, we were tasked to resolve the HVAC system design fo...

Evaporative Condenser Access and Mainten...

Providing safety access platforms for evaporative condensers...

Lubricant Related Compressor Failures

If you strip away all the marketing noise around lubricants,...

Aged Care Homes Comfort Envelope

Comfort in aged care homes is not just about setting the the...

Predictive Maintenance and Condition Mon...

So, what is predictive maintenance? How do you use condition...

AS 1668.2 bathroom and toilet exhaust ve...

Use this AS 1668.2 bathroom and toilet exhaust ventilation c...

Infrared heating

When you walk into a warehouse or sports arena with high-bay...

Air and human comfort

Space explorations to the moon, other planets, and beyond ha...

Why Supermarket Refrigeration and HVAC M...

There is a tendency on some projects to treat refrigeration ...

Low dT, pump control and why DP reset ma...

Low ΔT in a chilled water system is often misunderstoo...

ASNZS 5149 Refrigerant Charge Limit Calc...

Use this AS/NZS 5149 refrigerant charge limit calculator to ...

What is an Air Conditioner Evaporator Co...

The evaporator is a heat exchanger that operates on the same...

How Do Air Conditioners Work

The principal role of air conditioning is to maintain a comf...

High Latent Load Dehumidification Reheat...

Use this calculator to check high latent load cooling and de...

How to verify the percentage of outside ...

Use this outside air percentage calculator to estimate how m...

Why is my class room stale!

Those were the days my chief engineer checked all my designs...

How to calculate room pressurisation

Use this room pressurisation calculator to estimate the airf...

Guideline 36-2021: High Performance Sequ...

A field study on ASHRAE Guideline 36 revealed a hard truth. ...

ASNZS 60079.10 Hazardous Area Ventilatio...

Use this to calculate hazardous atmosphere ventilation rate ...

What consultants must learn from Lacross...

Disclaimer: The below is provided for general information an...

UN SDGs, good intentions, wrong priority...

The United Nations Sustainable Development Goals (UN SDGs), ...

How Does Refrigerant Work in Refrigerati...

Here are some typical operating conditions. As pressures dif...

AS 1668.4 Natural Ventilation Opening Ar...

Use this calculator to estimate minimum natural ventilation ...

Stair Pressurisation Calculator

This stair pressurisation calculator estimates the prelimina...

Split System Air Conditioners Installati...

The split system air conditioner has two parts: the indoor a...

Calculate Pump Motor Power

Use this pump motor power calculator to estimate the power r...

Indoor pool and wellness centre

Use this indoor pool and wellness centre calculator to estim...

Low dT, pump control and why DP reset ma...

Low ΔT in a chilled water system is often misunderstoo...

The Physiological Basis for Air Conditio...

Seasonal extremes of heat and cold are often outside the ran...

Deteriorated Busbar Insulation is a Seri...

The busbar insulation has deteriorated, exposing the live co...

Why Your High Efficient Condensing Boile...

Now that you have installed the high-efficiency condensing b...

The Evaporation of R22

Let’s take a cylinder of R22 at an ambient temperature...

Primary Secondary Chilled Water Decouple...

Why do primary secondary chilled water systems use a decoupl...

Solar PV Air Conditioner Sizing

Use this calculator to calculate how many solar panels are r...

Thermal Insulation R-Value and U-Value C...

Use this calculator to calculate R-value and U-value from in...

Passive House (Haus) Designs, Heat Recov...

The rise of Passive House design has fundamentally reshaped ...

How to verify the percentage of outside ...

Use this outside air percentage calculator to estimate how m...

Calculate Fan Motor Power

Use this fan motor power calculator to estimate the power re...

Natural Ventilation Designs

 https://www.monodraught.com/https://greenhome.osu.edu/...

Small in Window Air Conditioner Units In...

As its name suggests, unitary window air conditioners consis...

Stair pressurisation system

Stair pressurisation systemDoor average area: 2.1m2Design nu...

What Happens in the Cold Heat Exchanger

Remember that R22 refrigerant vaporises at -42°C at atmo...

How reciprocating compressors work in ai...

The reciprocating compressors (piston compressors or recip c...

Duct Heat Gain and R-Value Insulation Ca...

Use this calculator to estimate duct heat gain as a percenta...

What Happens When All AHU Dampers Are Cl...

A serious design problem occurs when all available airflow p...

AS1668.2 2012 Appendix A Minimum OA

Use this AS 1668.2 outdoor air ventilation rate look up tool...

What do you want from your BMS 2/3

Before I answer the question, let’s look at the diagra...

Air and human comfort

Space explorations to the moon, other planets, and beyond ha...

Chiller System Designs Mistakes

Chilled water systems can become inefficient, unstable or ex...

Lesson learnt from Year 7 maths, when is...

Lesson learnt from Year 7 maths: when is 1 + 1 = 10?At first...

Can a Supermarket Really Cut Energy Use ...

A claim of 50% energy savings sounds ambitious, particularly...

How to size buffer tank

Buffer tank sizing is not an arbitrary exercise. Typical gui...

Air conditioning back to basic principle...

Air conditioning basic principlesThe basis for air condition...

What is P, PI & PID controls

  An open loop system operates without feedback, i...

Gas Detectors-Ammonia Refrigerant

Average Person Sensible and Latent Heat ...

Use this calculator to estimate the sensible and latent heat...

What consultants must learn from Lacross...

Disclaimer: The below is provided for general information an...

Stair Pressurisation Calculator

This stair pressurisation calculator estimates the prelimina...

Correct installation of expansion vessel

Expansion vessels are often treated as simple pipework acces...

ASNZS 60079.10 Hazardous Area Ventilatio...

Use this to calculate hazardous atmosphere ventilation rate ...

What is P, PI & PID controls

  An open loop system operates without feedback, i...

Understanding the Psychrometric Chart

Although engineers and technicians need to know how the valu...

Why is my class room stale!

Those were the days my chief engineer checked all my designs...

Geospatial 3D Point Cloud Laser Scanning

Geospatial 3D point cloud laser scanning is a method of capt...

How Does Refrigerant Work in Refrigerati...

Here are some typical operating conditions. As pressures dif...

What is Boiling

The first step to understanding how the air conditioning ref...

Generator Room Ventilations

Use this generator room ventilation calculator to estimate t...

Fire rated sealants

Fire-rated sealants are required where services, pipes, duct...

Deteriorated Busbar Insulation is a Seri...

The busbar insulation has deteriorated, exposing the live co...

HVAC calculators and Estimators

Free HVAC calculators and estimators for cooling, heating, a...

Refrigeration Cycle P-H Diagram Calculat...

Use this free HVAC Refrigeration P-H Diagram Calculator to b...

Infrared heating

When you walk into a warehouse or sports arena with high-bay...

How to Size a Chiller

Sizing a chiller is more than selecting a machine with the s...

Chiller Sizing FAQs

This chiller sizing FAQ answers common questions about selec...

Room Noise Predictor From AHU to Diffuse...

Use this room noise predictor to estimate the expected noise...

Comparison of UVC, UVC LED and Far-UVC f...

For AHU cooling coil disinfection, conventional 254 nm UVC m...

AS 1668.2 Kitchen Exhaust Calculator

Use this AS 1668.2 kitchen exhaust calculator to estimate mi...

How to Size U-Trap - AS/NZS 3666.1

Why is u-trap important and how to size an u-trap for air ha...

What is Condenser in Air Conditioning Sy...

The air-cooled condenser is a heat exchanger. What is the fu...

How a chiller controls its capacity and ...

A chiller controls its capacity mainly by maintaining the le...

What do you want from your BMS 3/3

What do you want from your BMS. Part 3: Direct Expansion Eva...

Stair Pressurisation Calculator

This stair pressurisation calculator estimates the prelimina...

Is water boiling point always at 100C

Is Water Boiling Point always at 100°CThe temperature of...

Design, construction and fit-out of food...

Practical Guide for Western Australian Food PremisesDesignin...

What consultants must learn from Lacross...

Disclaimer: The below is provided for general information an...

What is an Air Conditioner Evaporator Co...

The evaporator is a heat exchanger that operates on the same...

Is water boiling point always at 100C

Is Water Boiling Point always at 100°CThe temperature of...

What do you want from your BMS 3/3

What do you want from your BMS. Part 3: Direct Expansion Eva...

Cooling Coil Bypass Factor Calculator

Use this calculator to estimate cooling coil bypass factor u...

Aged Care Homes Comfort Envelope

Comfort in aged care homes is not just about setting the the...

Understanding the Psychrometric Chart

Although engineers and technicians need to know how the valu...

ASNZS 5149 Refrigerant Charge Limit Calc...

Use this AS/NZS 5149 refrigerant charge limit calculator to ...

How to Size a Chiller

Sizing a chiller is more than selecting a machine with the s...

Preliminary Cooling Load Estimation

Use this preliminary cooling load estimator to calculate an ...

NCC2025 Part J6D9 Pipework insulation

Updated to NCC 2025(1) Piping, vessels, heat exchangers and ...

Natural Ventilation Design Mistakes

Natural ventilation can reduce mechanical cooling and fan en...

Refrigerant R22

Before we get ahead of ourselves, R22 will phase out in Aust...

Chiller System Designs Checklist

Before finalising the chiller selection, review the followin...

Water Cooled Chiller Sizing Calculator

Use this water-cooled chiller sizing calculator to estimate ...

What Happens When All AHU Dampers Are Cl...

A serious design problem occurs when all available airflow p...

Relative Pressure and Absolute Pressure

Relative Pressure and Absolute PressureThe deeper divers go ...

How to calculate room pressurisation

Use this room pressurisation calculator to estimate the airf...

So What is New in Refrigerant?

From CFCs to HFOs, how Refrigerant Policy Evolved from Ozone...

BCA Climate Zone Interactive Map

BCA Climate Zone Interactive MapUse the ACBC climate map to ...

AS 1668.2 bathroom and toilet exhaust ve...

Use this AS 1668.2 bathroom and toilet exhaust ventilation c...

Heat transfer

Air conditioning is concerned with heat flow processes. Heat...

Refrigeration Cycles

As its name indicates, it’s in the evaporator that the...

Solar Air Conditioning

Solar energy has always been attractive to the building serv...

Calculate Fan Motor Power

Use this fan motor power calculator to estimate the power re...

AS 1668.2 Minimum Outdoor Airflow Rate C...

Use this AS 1668.2 Minimum Outdoor Airflow Rate Calculator t...

Constant Airflow Regulator

How to Size U-Trap - AS/NZS 3666.1

Why is u-trap important and how to size an u-trap for air ha...

Connecting a 50hz induction motor and ru...

What happens if connecting a 50hz induction motor to 60hz po...

Duct Heat Gain and R-Value Insulation Ca...

Use this calculator to estimate duct heat gain as a percenta...

Evaporative cooler sizing

Use this evaporative cooler sizing calculator to estimate th...

AS 1668.2 Kitchen Exhaust Calculator

Use this AS 1668.2 kitchen exhaust calculator to estimate mi...

Maisotsenko Cycle

Water Cooled Chiller Sizing Calculator

Use this water-cooled chiller sizing calculator to estimate ...

Henrys Law and Cavitation

Henry's Law and cavitationEver wondered why a perfectly ...

Plate Heat Exchanger Sizing Calculator

Use this liquid plate heat exchanger sizing calculator to es...

Evaporative Condenser Access and Mainten...

Providing safety access platforms for evaporative condensers...

The Role of the Compressor

Think back to the hot heat exchanger and the black grille be...

Comparison with P, PI & PID

Average Person Sensible and Latent Heat ...

Use this calculator to estimate the sensible and latent heat...

AS 1668.4 Natural Ventilation Opening Ar...

Use this calculator to estimate minimum natural ventilation ...

How reciprocating compressors work in ai...

The reciprocating compressors (piston compressors or recip c...

NCC2025 Part J6D9 Pipework insulation

Updated to NCC 2025(1) Piping, vessels, heat exchangers and ...

Natural Ventilation Designs

 https://www.monodraught.com/https://greenhome.osu.edu/...

Conflict of Air Tightness Buildings and ...

Conflict of Air Tightness Buildings and Fire SafetyModern bu...

UN SDGs, good intentions, wrong priority...

The United Nations Sustainable Development Goals (UN SDGs), ...

How to verify the percentage of outside ...

Use this outside air percentage calculator to estimate how m...

Far Ultraviolet Germicidal Irradiation (...

Far-UVC Ultraviolet Germicidal Irradiation (UVGI)What do you...

Lubricant Related Compressor Failures

If you strip away all the marketing noise around lubricants,...

What is Thermal Expansion Valve (TX Valv...

All air conditioning refrigeration circuits have expansion d...

Calculate Pump Motor Power

Use this pump motor power calculator to estimate the power r...

Is Water a Good Refrigerant

Let’s remind ourselves of these two basic rules:There ...

Geospatial 3D Point Cloud Laser Scanning

Geospatial 3D point cloud laser scanning is a method of capt...

Indirect Evaporative Cooling-The Univers...

In 2011, we were tasked to resolve the HVAC system design fo...

Dehumidified IEC System

TOTAL DEHUMIDIFIED IEC

Plate Heat Exchanger Sizing Calculator

Use this liquid plate heat exchanger sizing calculator to es...

Cost Saving Electronically Commutated (E...

One of the common reasons to adopt electronically commutated...

Where Does the Energy Actually Go in a S...

Before trying to save energy, it helps to know where it is b...

Chiller System Designs Mistakes

Chilled water systems can become inefficient, unstable or ex...

Understanding the Psychrometric Chart

Although engineers and technicians need to know how the valu...

The Evaporation of R22

Let’s take a cylinder of R22 at an ambient temperature...

Water use by cooling towers

Use this cooling tower water use calculator to estimate the ...

Constant Airflow Regulator

Natural Ventilation Design Mistakes

Natural ventilation can reduce mechanical cooling and fan en...

ASNZS 5149 Refrigerant Charge Limit Calc...

Use this AS/NZS 5149 refrigerant charge limit calculator to ...

ASNZS 60079.10 Hazardous Area Ventilatio...

Use this to calculate hazardous atmosphere ventilation rate ...

Removing Mould and Mould Stains

Removing Mouldconcrobium.com/en-au/Walk into Bunnings or har...

Why Cycling Condenser Fans Can Waste Sup...

Many refrigeration condensers control capacity by switching ...

How to size buffer tank

Buffer tank sizing is not an arbitrary exercise. Typical gui...

The Phenomenon of Condensation

We’ve seen that to vaporise R22, that is, to change it...

HVAC calculators and Estimators

Free HVAC calculators and estimators for cooling, heating, a...

Condensate Tray Pondage Is an Installati...

Condensate trays must be graded to drain continuously and pr...

Lesson learnt from Year 7 maths, when is...

Lesson learnt from Year 7 maths: when is 1 + 1 = 10?At first...

Lubricant Related Compressor Failures

If you strip away all the marketing noise around lubricants,...

How to Size a Chiller

Sizing a chiller is more than selecting a machine with the s...

Primary Secondary Chilled Water Decouple...

Why do primary secondary chilled water systems use a decoupl...

How a chiller controls its capacity and ...

A chiller controls its capacity mainly by maintaining the le...

Henrys Law and Cavitation

Henry's Law and cavitationEver wondered why a perfectly ...

HVAC Duct Sizing Calculator

Use this calculator to calculate HVAC duct sizes using equal...

Properties of air-psychrometry

Air is the medium with which buildings are cooled and heated...

Conflict of Air Tightness Buildings and ...

Conflict of Air Tightness Buildings and Fire SafetyModern bu...

Personal Air Coolers

I reckon many personal air coolers are more marketing than e...

What do you want from your BMS 1/3

Fresh out of uni back in the days, sitting on some cement ba...

Preliminary Cooling Load Estimation

Use this preliminary cooling load estimator to calculate an ...

Fire rated sealants

Fire-rated sealants are required where services, pipes, duct...

Climate challenges ...

Climate change sits at the intersection of science, politics...

Stair Pressurisation Calculator

This stair pressurisation calculator estimates the prelimina...

Filters energy use

Filter True Cost CalculatorThe Filter True Cost Calculator i...

Far Ultraviolet Germicidal Irradiation (...

Far-UVC Ultraviolet Germicidal Irradiation (UVGI)What do you...

AS 1668.2 Mechanical Exhaust Ventilation...

Use this AS 1668.2 mechanical exhaust ventilation rate look-...

The Phenomenon of Condensation

We’ve seen that to vaporise R22, that is, to change it...

Understanding the Psychrometric Chart

Although engineers and technicians need to know how the valu...

Primary-Secondary Pumping, Flow, Mixing,...

Use this primary-secondary pumping calculator to check how f...

HVAC calculators and Estimators

Free HVAC calculators and estimators for cooling, heating, a...

ASNZS 60079.10 Hazardous Area Ventilatio...

Use this to calculate hazardous atmosphere ventilation rate ...

Primary Secondary Chilled Water Decouple...

Why do primary secondary chilled water systems use a decoupl...

AS 1668.2 Mechanical Exhaust Ventilation...

Use this AS 1668.2 mechanical exhaust ventilation rate look-...

Indirect Evaporative Cooling-The Univers...

In 2011, we were tasked to resolve the HVAC system design fo...

Passive House (Haus) Designs, Heat Recov...

The rise of Passive House design has fundamentally reshaped ...

How Do Air Conditioners Work

The principal role of air conditioning is to maintain a comf...

What do you want from your BMS 1/3

Fresh out of uni back in the days, sitting on some cement ba...

How Does Refrigerant Work in Refrigerati...

Here are some typical operating conditions. As pressures dif...

Cost Saving Electronically Commutated (E...

One of the common reasons to adopt electronically commutated...

Why Condenser Coil Fins Flaking and Fall...

When condenser fins become brittle, flake and fall apart whe...

High Latent Load Dehumidification Reheat...

Use this calculator to check high latent load cooling and de...

How a chiller controls its capacity and ...

A chiller controls its capacity mainly by maintaining the le...

Where Does the Energy Actually Go in a S...

Before trying to save energy, it helps to know where it is b...

Air Cooled Chiller Sizing Calculator

Use this air cooled chiller sizing calculator to estimate co...

AS 1668.2 2012 Car Park Exhaust Calculat...

Use this calculator to calculate the minimum exhaust airflow...

Wet bulb depression efficiency-evaporati...

For those who have been to Malaysia, the first thing you eve...

Outdoor-Air Intake Location and Indoor A...

Both AS 1668.2 and AS/NZS 3666.1 recognise that bringing out...

Dehumidified IEC System

TOTAL DEHUMIDIFIED IEC

Mould growth provisions for NCC 2022

Mould Growth Provisions for NCC 2022First published in Linke...

AS1668.2 2012 Appendix A Minimum OA

Use this AS 1668.2 outdoor air ventilation rate look up tool...

Guideline 36-2021: High Performance Sequ...

A field study on ASHRAE Guideline 36 revealed a hard truth. ...

Understanding the Psychrometric Chart

Although engineers and technicians need to know how the valu...

Infrared heating

When you walk into a warehouse or sports arena with high-bay...

What Happens in the Cold Heat Exchanger

Remember that R22 refrigerant vaporises at -42°C at atmo...

Correct installation of expansion vessel

Expansion vessels are often treated as simple pipework acces...

Natural Ventilation FAQ

Natural ventilation can be an effective way to provide outdo...

Climate challenges ...

Climate change sits at the intersection of science, politics...

Comparison of UVC, UVC LED and Far-UVC f...

For AHU cooling coil disinfection, conventional 254 nm UVC m...

HVAC Duct Sizing Calculator

Use this calculator to calculate HVAC duct sizes using equal...

How to size buffer tank

Buffer tank sizing is not an arbitrary exercise. Typical gui...

Air conditioning back to basic principle...

Air conditioning basic principlesThe basis for air condition...

Deteriorated Busbar Insulation is a Seri...

The busbar insulation has deteriorated, exposing the live co...

Geospatial 3D Point Cloud Laser Scanning

Geospatial 3D point cloud laser scanning is a method of capt...

Chiller Sizing Example

This worked example shows how to size a chiller for a commer...

Gas Detectors-Ammonia Refrigerant

AS 1668.2 2012 Car Park Exhaust Calculat...

Use this calculator to calculate the minimum exhaust airflow...

Natural Ventilation Designs

 https://www.monodraught.com/https://greenhome.osu.edu/...

Fire rated sealants

Fire-rated sealants are required where services, pipes, duct...

Comparison with P, PI & PID

The Physiological Basis for Air Conditio...

Seasonal extremes of heat and cold are often outside the ran...

What Happens When All AHU Dampers Are Cl...

A serious design problem occurs when all available airflow p...

Relative Pressure and Absolute Pressure

Relative Pressure and Absolute PressureThe deeper divers go ...

Split System Air Conditioners Installati...

The split system air conditioner has two parts: the indoor a...

So What is New in Refrigerant?

From CFCs to HFOs, how Refrigerant Policy Evolved from Ozone...

Laboratory Airflow Control Devices Air V...

Design, construction and fit-out of food...

Practical Guide for Western Australian Food PremisesDesignin...

Chiller Power Consumption Calculation Us...

Use this chiller power consumption calculator to estimate ch...

Natural Ventilation Requirements in Aust...

Natural ventilation is one of the simplest ways to provide o...

Heat transfer

Air conditioning is concerned with heat flow processes. Heat...

Vibration calculator

Vibration CalculatorUse this vibration calculator to estimat...

So What is New in Refrigerant?

From CFCs to HFOs, how Refrigerant Policy Evolved from Ozone...

Infrared heating

When you walk into a warehouse or sports arena with high-bay...

Personal Air Coolers

I reckon many personal air coolers are more marketing than e...

Calculate Fan Motor Power

Use this fan motor power calculator to estimate the power re...

Split System Air Conditioners Installati...

The split system air conditioner has two parts: the indoor a...

Natural Ventilation Design Mistakes

Natural ventilation can reduce mechanical cooling and fan en...

Commercial Kitchen Ventilation Designs

Commercial Kitchen Ventilation DesignsAmong the frequent que...

Chiller Sizing FAQs

This chiller sizing FAQ answers common questions about selec...

What Happens When All AHU Dampers Are Cl...

A serious design problem occurs when all available airflow p...

Duct Heat Gain and R-Value Insulation Ca...

Use this calculator to estimate duct heat gain as a percenta...

Outdoor-Air Intake Location and Indoor A...

Both AS 1668.2 and AS/NZS 3666.1 recognise that bringing out...

What is Thermal Expansion Valve (TX Valv...

All air conditioning refrigeration circuits have expansion d...

Stair Pressurisation Calculator

This stair pressurisation calculator estimates the prelimina...

How to size buffer tank

Buffer tank sizing is not an arbitrary exercise. Typical gui...

Constant Airflow Regulator

Refrigeration Cycle P-H Diagram Calculat...

Use this free HVAC Refrigeration P-H Diagram Calculator to b...

Legacy AHU Supply air fan speed control ...

Legacy Supply Air Fan Speed Control, A Smarter Way to Save E...

Chiller Sizing Calculator

Use this chiller sizing calculator to estimate key HVAC chil...

What Happens in the Cold Heat Exchanger

Remember that R22 refrigerant vaporises at -42°C at atmo...

Is water boiling point always at 100C

Is Water Boiling Point always at 100°CThe temperature of...

Natural Ventilation FAQ

Natural ventilation can be an effective way to provide outdo...

ERV energy recovery calculator

Use this HVAC air-to-air heat exchanger and ERV calculator t...

Why is my class room stale!

Those were the days my chief engineer checked all my designs...

Air conditioning back to basic principle...

Air conditioning basic principlesThe basis for air condition...

Outdoor-Air Intake Location and Indoor A...

Both AS 1668.2 and AS/NZS 3666.1 recognise that bringing out...

Deteriorated Busbar Insulation is a Seri...

The busbar insulation has deteriorated, exposing the live co...

AS 1668.2 2012 Car Park Exhaust Calculat...

Use this calculator to calculate the minimum exhaust airflow...

Correct installation of expansion vessel

Expansion vessels are often treated as simple pipework acces...

Cost Saving Electronically Commutated (E...

One of the common reasons to adopt electronically commutated...

How to verify the percentage of outside ...

Use this outside air percentage calculator to estimate how m...

Ground Source Heat Pump Size Estimator

Use this ground source heat pump size estimator to assess pr...

What Happens in the Cold Heat Exchanger

Remember that R22 refrigerant vaporises at -42°C at atmo...

Solar Air Conditioning

Solar energy has always been attractive to the building serv...

UN SDGs, good intentions, wrong priority...

The United Nations Sustainable Development Goals (UN SDGs), ...

What consultants must learn from Lacross...

Disclaimer: The below is provided for general information an...

What is Refrigeration and Air Conditioni...

Are you looking to learn and take an air conditioning course...

What is Condenser in Air Conditioning Sy...

The air-cooled condenser is a heat exchanger. What is the fu...

Generator Room Ventilations

Use this generator room ventilation calculator to estimate t...

Why Supermarket Refrigeration and HVAC M...

There is a tendency on some projects to treat refrigeration ...

Preliminary Cooling Load Estimation

Use this preliminary cooling load estimator to calculate an ...

Comparison with P, PI & PID

Laboratory Airflow Control Devices Air V...

Heat transfer

Air conditioning is concerned with heat flow processes. Heat...

Where Does the Energy Actually Go in a S...

Before trying to save energy, it helps to know where it is b...

Air and human comfort

Space explorations to the moon, other planets, and beyond ha...

Dehumidification load in swimming pool

Use this swimming pool dehumidification load calculator to e...

What do you want from your BMS 2/3

Before I answer the question, let’s look at the diagra...

Evaporative cooler sizing

Use this evaporative cooler sizing calculator to estimate th...

Small in Window Air Conditioner Units In...

As its name suggests, unitary window air conditioners consis...

Engineering innovation, is creativity th...

Engineering is often seen as a discipline of rules, standard...

The Refrigeration Gauges

Let’s examine the refrigeration pressure gauge: this i...

Calculate Pump Motor Power

Use this pump motor power calculator to estimate the power r...

Carpark exhaust control

How Does Refrigerant Work in Refrigerati...

Here are some typical operating conditions. As pressures dif...

How to Size U-Trap - AS/NZS 3666.1

Why is u-trap important and how to size an u-trap for air ha...

ERV energy recovery calculator

Use this HVAC air-to-air heat exchanger and ERV calculator t...

Why Cycling Condenser Fans Can Waste Sup...

Many refrigeration condensers control capacity by switching ...

The Evaporation of R22

Let’s take a cylinder of R22 at an ambient temperature...

Fire rated sealants

Fire-rated sealants are required where services, pipes, duct...

Outdoor-Air Intake Location and Indoor A...

Both AS 1668.2 and AS/NZS 3666.1 recognise that bringing out...

Where Does the Energy Actually Go in a S...

Before trying to save energy, it helps to know where it is b...

Personal Air Coolers

I reckon many personal air coolers are more marketing than e...

Floating Head Pressure is among the Bigg...

A refrigeration compressor does more work when it has to com...

Natural Ventilation Requirements in Aust...

Natural ventilation is one of the simplest ways to provide o...

Geospatial 3D Point Cloud Laser Scanning

Geospatial 3D point cloud laser scanning is a method of capt...

Chiller Sizing Example

This worked example shows how to size a chiller for a commer...

Relationship Between Pressure and Temper...

Relationship between Pressure and Temperature If you lo...

Split System Air Conditioners Installati...

The split system air conditioner has two parts: the indoor a...

How to size buffer tank

Buffer tank sizing is not an arbitrary exercise. Typical gui...

Primary-Secondary Pumping, Flow, Mixing,...

Use this primary-secondary pumping calculator to check how f...

What is Boiling

The first step to understanding how the air conditioning ref...

Comparison with P, PI & PID

AS 1668.2 Kitchen Exhaust Calculator

Use this AS 1668.2 kitchen exhaust calculator to estimate mi...

Heat energy and change of phase

Heat energy and change of phaseComfort air conditioning syst...

Condensate Tray Pondage Is an Installati...

Condensate trays must be graded to drain continuously and pr...

Where Does the Energy Actually Go in a S...

Before trying to save energy, it helps to know where it is b...

What is Thermal Expansion Valve (TX Valv...

All air conditioning refrigeration circuits have expansion d...

Solar Absorption Chiller Sizing Calculat...

Use this calculator to estimate solar collector area, storag...

The Refrigeration Gauges

Let’s examine the refrigeration pressure gauge: this i...

How to Size U-Trap - AS/NZS 3666.1

Why is u-trap important and how to size an u-trap for air ha...

Indoor pool and wellness centre

Use this indoor pool and wellness centre calculator to estim...

What is Boiling

The first step to understanding how the air conditioning ref...

Hydronics heating, how to increase conde...

What is an efficient condensing boiler, to be exactly how sh...

Lubricant Related Compressor Failures

If you strip away all the marketing noise around lubricants,...

How to size buffer tank

Buffer tank sizing is not an arbitrary exercise. Typical gui...

Room Pressurisation Leakage and Fan Airf...

Use this calculator to estimate the airflow required to main...

Relative Pressure and Absolute Pressure

Relative Pressure and Absolute PressureThe deeper divers go ...

The Role of the Compressor

Think back to the hot heat exchanger and the black grille be...

Room Noise Predictor From AHU to Diffuse...

Use this room noise predictor to estimate the expected noise...

Predictive Maintenance and Condition Mon...

So, what is predictive maintenance? How do you use condition...

Natural Ventilation Requirements in Aust...

Natural ventilation is one of the simplest ways to provide o...

Fire rated sealants

Fire-rated sealants are required where services, pipes, duct...

What Happens in the Cold Heat Exchanger

Remember that R22 refrigerant vaporises at -42°C at atmo...

Climate challenges ...

Climate change sits at the intersection of science, politics...

Is water boiling point always at 100C

Is Water Boiling Point always at 100°CThe temperature of...