Hydrotest in HVAC Systems (AHU & Chiller Piping)

Hydrotest in HVAC Systems (AHU & Chiller Piping)

Hydrostatic testing is a critical step in HVAC commissioning to ensure strength, safety, and leak-free operation of chilled water systems before insulation and startup.

Why Hydrotest ?

Detects leakage in joints, valves & welds
Verifies piping strength under pressure
Ensures long-term system reliability

Key Standard:

Test Pressure = 1.5 x Working Pressure

(Example: 6 bar → 9 bar)

Where It's Applied?

Chilled water piping (CHW supply & return)
AHU coil connections
Headers, risers & valve sections

Basic Procedure:

1. Line preparation & flushing

2. Filling with water (air removal is critical)

3. Gradual pressurization

4. Pressure holding (2-24 hrs)

5. Inspection for leakage & pressure drop

Common Mistakes to Avoid:

Air trapped inside pipeline
Sudden pressurization
Not isolating AHU/Chiller
Using uncalibrated gauges

Final Step:

Proper documentation & consultant approval

A successful hydrotest ensures your HVAC system is ready for efficient and safe operation.

Comments

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