Clean, Dry Air Requirements for Oxygen Concentrators

High concentration ozone generators rely on oxygen concentrators. For technicians and customers operating oxygen concentrators (oxygen generators), one of the most common causes of failure is improper supply air. Many users either don’t realize they must provide clean, dry compressed air, or they are unsure what that actually means.

This guide defines the requirements and explains why they are critical to long-term performance.

Minimum Air Requirements

Oxygen concentrators using external or plant compressed air should meet the following:

Air Quality: ISO8573.1 Class 1.4.1
Air Pressure: Minimum 90 PSI
Air Temperature: Maximum 100°F (38°C)

These specifications should be included in quotes, manuals, and installation documentation.

Why Clean, Dry Air is Critical

The molecular sieve material is the core component inside oxygen concentrators. Under proper conditions, it can last 3–7 years while producing high-purity oxygen.

However, moisture and oil contamination quickly destroy the sieve material, and lead to more problems:

Oxygen purity drops
Production output decreases
Ozone generator cells may be damaged
Costly repairs and downtime occur

Leading causes of sieve failure

Moisture in supply air (most common)
Oil contamination
High temperature air
Dust and particulate contamination

Even moderate contamination can destroy sieve beds within days.

Plant Air–Fed Units

Air quality requirements for filtered air:

Dry – dew point of 38 degrees F or lower
Clean – particle size of .1 micron or less
Oil-free – less than or equal to 0.01 mg/m^3

Hot, humid, dirty, or oily air rapidly degrades molecular sieve performance.

Pressure Requirement

Incoming air pressure must be at least 90 PSI (6.2 bar).

Ensures low dew point
Ensures adequate air flow through suitable pressure regulator

Temperature Requirement

Compressed air must be 100°F (38°C) or lower. Hot air holds significantly more water vapor than cool air and contributes to the following problems:

Reduce efficiency
Increase moisture content
Damage sieve material over time

Recommended Air System Components

Most installations require the following components:

Aftercooler
Refrigerated air dryer
Air storage/surge tank
Filtration system

These components remove moisture before the air reaches the oxygen generator.

Built-In Air Inlet Filter

All oxygen concentrators include a secondary filter at the Air-IN connection with a clear bowl.

This filter is:

NOT the primary air treatment
Only a backup safeguard
Should remain clean and dry

Check daily.
If moisture or contamination appears, the upstream air system requires immediate attention.

Compressor Maintenance Requirements

To maintain proper air quality, perform these maintenance steps:

Drain condensation from air tanks regularly
Blow out air distribution lines
Replace internal filter element every 6 months
Maintain compressor per manufacturer instructions

Pipe scale, oil carryover, and water vapor must be minimized for long-term operation.

Units With Built-In Compressors

The location for the installation of oxygen concentrator equipment with built-in compressors is critical.

Air-conditioned space (recommended)
Temperature range: 40°F – 100°F (5°C – 38°C)
Clean air environment
Low humidity area

Environments containing the following contaminants must be avoided:

Oil vapor
Ammonia
Hydrocarbons
Carbon monoxide
High humidity

Ammonia exposure will cause immediate, irreversible sieve damage.

Automatic Condensate Drain

Units with onboard compressors include the following components:

Filter system
Automatic condensate drain
Timer (every 10–15 minutes)

These should be checked daily to confirm proper operation and verify bowls remain dry.

Understanding Dew Point and Moisture

Air drying works by cooling air until moisture condenses and drains away.

The dew point indicates how much water vapor is present.

Example moisture content:

Dew Point	Water per m³
0°F	1.08 g
40°F	6.55 g
80°F	25.22 g

Higher dew point = more moisture = faster sieve damage.

Clean Dry Air

How Much Water Enters a Concentrator?

A small 10 LPM oxygen concentrator processes 5,760 cubic feet of air per day.

At an 80°F dew point, this equals approximately one gallon of water entering the sieve material every 24 hours.

Impact of this moisture:

Reduces oxygen output
Degrades zeolite material
Causes early failure

Dew Point vs. Sieve Life

30–50°F dew point
Comfortable room air
Expected life: 15,000–20,000 hours (~2 years)

50–65°F dew point
Humid/sticky conditions
Expected life: 10,000–12,000 hours (~1 year)

Above 65°F dew point
Tropical/muggy conditions
Sieve failure within weeks

Recommended target:
≤ 50°F dew point

Pressure Dew Point (PDP)

When air is compressed, water condenses at a higher temperature. This is called Pressure Dew Point (PDP).

Example:

Ambient air
80°F temperature
65°F dew point

Compressed to ~40 PSI then cooled back to 80°F:

New dew point ≈ 50°F
(Borderline acceptable)

Proper cooling inside the concentrator is critical to achieving this.

Best Installation Practices

Best option: Install concentrator in air-conditioned room

Next best option: Use refrigerated air dryer (20–40°F dew point)

This significantly extends sieve material life.

External Refrigerated Air Dryer Option

Our TOX concentrators support external refrigerant air dryers for high dew-point environments: https://www.oxidationtech.com/tox-20.html

These units can also accept clean, dry plant air from an existing compressed air system.

Additional Resources

Industrial High-Pressure Molecular Sieve
https://www.oxidationtech.com/xp-molecular-sieve.html

Low Pressure Sieve Beds
https://www.oxidationtech.com/oxo10-module.html

Dry Air Feed Gas for Ozone Generators
https://www.oxidationtech.com/ozone/ozone-generation/o3-feed-gas.html