How long should a return air duct be?

Your Return Ducts' Dimensions: If you're only installing one or two return vents, a 12-inch return is recommended for 2-ton and lesser units. For ages 3 and above, 14 inches is recommended. For 4 tonne systems, 16-inch returns should suffice, however 5 tonne systems may require 18-inch returns.

Course Content

Introduction to HVAC

6m 3s

Fundamental of Thermodynamics

3m 6s

Properties of a System

11m 14s

Pure Substance in Thermodynamics Laws of Thermodynamics

12m 13s

Fundamental of Heat Transfer

8m 24s

Overview of HVAC Systems

10m 54s

VCR Cycle

11m 12s

Fundamentals of RAC

11m 51s

Refrigerants in HVAC

14m 31s

Assignment : Fundamental of Thermodynamics

3m 6s

Quiz : Fundamentals Of ThermoDynamics

Fundamental of Psychrometry

21m 38s

Psychrometric Process

8m 34s

Assignment : Psychometry

2m 20s

Quiz : Psychrometry

Classification of AC

20m 54s

Non Centralized AC (Windows & Split) Centralized AC

15m 48s

Air Handling Unit (AHU)

10m 11s

Chiller Water System

20m 46s

Package System, VRV & VRF System

14m 13s

Assignment : Classification of AC

3m 46s

Quiz : classification Of AC

Introduction to Heat Load

34m 9s

Heat Load Calculation for Bedroom

01h 12m 33s

Heat Load Calculation for Hostel

01h 4m 37s

Heat Load Calculation for Dinning

18m 18s

Introduction to HAP - Hourly Analysis Program

28m 5s

Head Load Calculation on HAP

38m 42s

Assignment : Heat Load

5m 46s

Quiz : Heat load

Introduction About Ducting

27m

Duct Fittings - part 1

24m 33s

Duct Fittings - part 2

13m 18s

Duct Annotation

29m 11s

Single Line Diagram (SLD)

11m 22s

Level-1 Double Line Diagram (DLD)

17m 38s

Level-2 Double Line Diagram (DLD)

17m 30s

Duct Design Accessories and Connection Pipes

31m 56s

Section View and Duct Size Reducer

43m 54s

Return Duct Design

41m 16s

Creating Plenum Box-Creation and Size

35m 45s

Total Static Pressure Loss Using Software

25m 44s

ISP & Blower Selection

15m 21s

Assignment : Air Distribution

3m 57s

Quiz : Air Distribution System

Introduction to Hydronic System

10m 51s

Pipe Design, Fittings and FCUs

37m 43s

Types of Valves

15m 42s

Drainage Pipes

8m 5s

Pipe Loss Calculation and Pump Selection

10m 18s

Assignment : Hydronic System

3m 39s

Quiz : Hydronic System

Ventilation

29m 46s

Fresh Air Calculation

14m 3s

Clean Room

20m 6s

Assignment : Clean Room

2m 5s

Assignment : Fresh Air

2m 17s

Assignment : Ventilation

2m 23s

Quiz : ventilation

Industry Level Project in HVAC

01h 2m 24s

HVAC Equipment

17m 43s

Course Summary

4m 7s

Interview Questions in HVAC

21m 43s

Career Guideline

2m 12s

Return Duct Design

HVAC Course Air Distribution System

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Discussion

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return duct

Course Content

Introduction to HVAC

6m 3s

Fundamental of Thermodynamics

3m 6s

Properties of a System

11m 14s

Pure Substance in Thermodynamics Laws of Thermodynamics

12m 13s

Fundamental of Heat Transfer

8m 24s

Overview of HVAC Systems

10m 54s

VCR Cycle

11m 12s

Fundamentals of RAC

11m 51s

Refrigerants in HVAC

14m 31s

Assignment : Fundamental of Thermodynamics

3m 6s

Fundamental of Psychrometry

21m 38s

Psychrometric Process

8m 34s

Assignment : Psychometry

2m 20s

Classification of AC

20m 54s

Non Centralized AC (Windows & Split) Centralized AC

15m 48s

Air Handling Unit (AHU)

10m 11s

Chiller Water System

20m 46s

Package System, VRV & VRF System

14m 13s

Assignment : Classification of AC

3m 46s

Introduction to Heat Load

34m 9s

Heat Load Calculation for Bedroom

01h 12m 33s

Heat Load Calculation for Hostel

01h 4m 37s

Heat Load Calculation for Dinning

18m 18s

Introduction to HAP - Hourly Analysis Program

28m 5s

Head Load Calculation on HAP

38m 42s

Assignment : Heat Load

5m 46s

Introduction About Ducting

27m

Duct Fittings - part 1

24m 33s

Duct Fittings - part 2

13m 18s

Duct Annotation

29m 11s

Single Line Diagram (SLD)

11m 22s

Level-1 Double Line Diagram (DLD)

17m 38s

Level-2 Double Line Diagram (DLD)

17m 30s

Duct Design Accessories and Connection Pipes

31m 56s

Section View and Duct Size Reducer

43m 54s

Return Duct Design

41m 16s

Creating Plenum Box-Creation and Size

35m 45s

Total Static Pressure Loss Using Software

25m 44s

ISP & Blower Selection

15m 21s

Assignment : Air Distribution

3m 57s

Introduction to Hydronic System

10m 51s

Pipe Design, Fittings and FCUs

37m 43s

Types of Valves

15m 42s

Drainage Pipes

8m 5s

Pipe Loss Calculation and Pump Selection

10m 18s

Assignment : Hydronic System

3m 39s

Ventilation

29m 46s

Fresh Air Calculation

14m 3s

Clean Room

20m 6s

Assignment : Clean Room

2m 5s

Assignment : Fresh Air

2m 17s

Assignment : Ventilation

2m 23s

Industry Level Project in HVAC

01h 2m 24s

HVAC Equipment

17m 43s

Course Summary

4m 7s

Interview Questions in HVAC

21m 43s

Career Guideline

2m 12s

FAQs

Electric heat pumps must be tested to UL 559 or UL 1995 standards. A 3.5 tonne heat pump is an example. For each 1000 BTU of cooling, the duct for this system must be sized utilising 6 square inches of transparent duct space. 12,000 BTU are contained in each tonne of cooling.

Return ducts are typically found in corridors, under stairwells, or in more open parts of your property. They must be properly installed and unobstructed. This positioning assures that they will be able to pull in sufficient air to return to the HVAC equipment.

Your Return Ducts' Dimensions:

If you're only installing one or two return vents, a 12-inch return is recommended for 2-ton and lesser units. For ages 3 and above, 14 inches is recommended. For 4 tonne systems, 16-inch returns should suffice, however 5 tonne systems may require 18-inch returns.

No, except in extreme instances where a closed chamber is temporarily under negative air pressure, an air return cannot be too large. Return vents are essential to the proper operation of any HVAC system because they maintain air pressure and filter out waste.