HVO Handheld Ultrasonic Oxygen Purity Tester

The HVO handheld ultrasonic oxygen purity tester is designed to measure the purity of oxygen produced by PSA oxygen concentrators. The HVO Ultrasonic Oxygen Purity Tester requires NO expensive replacement sensors, never requires calibration and is accurate to within plus/minus 1%.

To operate, take the 3/8” OD oxygen line leaving your oxygen concentrator or HVO system and connect it to the barbed fitting marked “inlet”. Once oxygen is flowing, press the activation button, wait about 10 seconds, and the percentage of oxygen purity will be displayed. The display will automatically power off after 60 seconds.

Made in the USA exclusively for High Volume Oxygen.

Note: You must restrict the oxygen flow to less than 10 liters per minute to get an accurate reading.

WARNING: Maximum pressure is 30 PSI. If you exceed 30 PSI you may permanently damage the unit.

Price: $250 + $18 for domestic shipping

To order, call (402) 476-0555 or use our contact form:

Oxygen Concentrators

For customers in the USA & Canada, we offer Airsep NewLife Intensity 10 and Philips Respironics M10 oxygen concentrators. For use outside of the USA and Canada, we recommend the Airsep NewLife Intensity, as it is available with 220/240V 60hz power. Both are excellent products.

NOTE: Not available and not recommended for use as a source of human medical oxygen.


Airsep NewLife Intensity 10

  • Power: 590 W 110-120V / 50 hz or 220-240V / 60 hz
  • 10 SLPM output @ 20 PSI

Philips Respironics M10

  • Power: 600 W 110-120V / 50 h
  • 10 SLPM output @ 10 PSI

Contact us for pricing.

Backup Oxygen Supply Valve

Backup Oxygen Supply Valve

The purpose of this optional, add-on product is to enable a backup supply of oxygen to automatically deliver gas if the HVO tank pressure drops below its normal regulator pressure. This might happen if, for example, you have a power failure, or a spike in oxygen demand.

The product is essentially a “T” that sits between a backup oxygen source, such as a compressed oxygen tank, and the HVO system. Each side requires a regulator, i.e. one for the HVO system and one for the backup supply, as shown in the diagram below.

Backup Oxygen Supply Valve Diagram

On the backup supply side there’s a ball valve (at right above) that enables the backup source to be turned off. On the HVO side there’s a check valve (at left above), a safety mechanism which ensures that the HVO tank won’t receive oxygen from a high-pressure supply. In the middle, there’s a “T” that connects to your oxygen-out line.

Let’s assume that your HVO system’s regulator is set to 55 PSI, while the regulator attached to the Backup Supply Valve is set to 50 PSI. If the HVO tank pressure drops below 50 PSI, the backup source would begin to deliver oxygen.

Price: $52 plus $10 domestic shipping

Respironics Internal HEPA Filter for Millennium M10 Oxygen Concentrators

The internal HEPA filters in your M10s should be changed every 2-3 years. Changing the filters regularly will maintain oxygen concentrator function and oxygen purity. If you want to test the purity output of your concentrators, you may be interested in our High Volume Oxygen purity tester (above).

Price: $25 domestic shipping included

Harris Low Pressure, High Flow Regulator

An oxygen-rated pressure regulator manufactured by Harris. This product is designed to provide maximum flow when combined with the the HVO system. Comes with a single analog pressure gauge and regulates up to 125 psi.

Note: The photo shows the regulator as it appears when installed on an HVO tank. The gauge behind the regulator gauge shows the pressure in the HVO tank, whereas the regulator gauge reflects the pressure on the outbound oxygen line. The second gauge and brass connectors are included.

Price: $150 + $25 domestic shipping

Refurbished Compressors

Occasionally HVO offers refurbished oilless Standard and Mighty Mite compressors as they become available after customer upgrades. Refurbished compressors have been disassembled, inspected, and reassembled to like new working condition. Comes with a one year, free replacement guarantee.

Standard: A WOB-L, single-piston compressor intended for installation in the HVO Standard system. Pressurizes the tank to a maximum of 100 PSI.

Mighty Mite: Made exclusively for High Volume Oxygen, this WOB-L, dual-piston compressor is intended for installation in the HVO Mighty Mite system. Refurbished with specially-engineered piston cups for heavy duty usage. Pressurizes the tank to a maximum of 150 PSI.

Prices start at $350 + shipping (to be calculated at order time)

HVO Adult Cotton T-Shirts

Men’s Style

  • Gildan Ultra Cotton Adult T-Shirt
  • 100 % Cotton – Preshrunk jersey knit; Tear away label
  • Sizes:
    • S – 18” width, 28” length
    • M – 20” width, 29” length
    • L – 22” width, 30” length
    • XL – 24” width, 31” length
    • XXL – 26” width, 32” length

Women’s Style V-Neck

  • Ultra-light cotton jersey
  • No neck tag
  • Hanes Women’s Nano-T V-Neck T-Shirt
  • 100% cotton
  • Sizes:
    • M (size 8-10) 36-37” bust 30.5-31.5” waist

Price: $18 including domestic shipping