Posted on Leave a comment

How to Care for your HVO System

You, When Everything is Working

You just made an investment in an HVO system because you want to save money on oxygen, have a safe work environment, and you like the idea of flipping a switch to make all the oxygen you need. Now you can focus on your business rather than having to check your tank levels, place orders, schedule delivery, replace empties, and pay oxygen bills.

To capitalize on your investment, put your system in a proper space and care for it so it can live a long and happy life. The things you need to do are pretty straightforward, especially if you begin with a little planning.

Quick Summary

  • Keep your system in a well-ventilated, low-dust, temperature-regulated, low–to-medium humidity space.
  • Plug your HVO headbox into a power-surge protector. Do NOT use power-surge protectors for the concentrators or relay boxes.
  • Clean the outer filters on your oxygen concentrators every 3-6 months. Replace the inner filters every 1-2 years, depending on how much dust is in your environment.

Choose a Cool, Dry Space for your System

Your HVO system is a machine that has moving parts. It will operate reliably in less-than-ideal conditions. However, just like your car, if you treat it well it is more likely to run well for a long time. Begin by finding a good location for your system. Ideal conditions are:

  1. Well-ventilated, with at least 10 CFM of air flow per 10 LPM oxygen concentrator. This is important if you will place your system in an enclosed space, such as a utility closet. If the system will be out in the open in a warehouse or shop setting, the system will most likely receive adequate ambient ventilation.
  2. Temperature regulated, ideally around 68°F / 20°C, but definitely no lower than 45°F / 7°C and no higher than 90°F / 32°C.
  3. Low to medium humidity, ideally 50% or less, but no higher than 90%
  4. Enough space surrounding the system so that there is ample air flow to the concentrators and the headbox air intake and exhaust

Regarding space requirements, we have found that all single-tank HVO systems with one to six concentrators require no more than a 3′ x 8′ footprint. It’s very convenient and space-efficient to place your oxygen concentrators on a wire rack that is 72″ H x 48″ W x 18″ D in size. That specific size can accommodate up to six concentrators on two shelves with room for two 3-outlet relay boxes, as shown below:

HVO Layout

Take Care of your Cons

Your oxygen concentrators separate oxygen from other gases found in the air using a mineral called zeolite. Zeolite looks like sand, but it has special adsorbent properties that make it attractive to nitrogen molecules. Under pressure, nitrogen clings to zeolite, leaving oxygen and trace amounts of other inert gases (mostly argon) free to leave the zeolite chamber or “sieve bed”, as it is known.

HVO Pro Gen 10

While under pressure, the oxygen in the sieve bed is vented out of the chamber. This is followed by a flush stage that clears and vents the nitrogen gas as exhaust. There are two sieve beds, so the process operates like a two-cylinder, two-cycle internal combustion engine in that one cylinder is venting while the other is producing oxygen.

If the zeolite sieve material becomes clogged with dust or water vapor, its efficiency decreases, which makes it less effective at removing nitrogen from air. In extreme cases, the efficiency may drop to zero, at which point you’ll need to replace the sieve material. Usually, the sieve beds can be replaced at a cost that is lower than replacement of the entire oxygen concentrator.

Important points to keep in mind:

  1. When an oxygen concentrator is running normally, it generates heat that dries the air as it enters the sieve beds. To prevent damage to the sieve material in your oxygen concentrators, never turn off a concentrator that is attached to the manifold of a running HVO system! When the compressor in the headbox runs, it will draw humid atmospheric air into the cold concentrator, which eventually (after many hours) may cause the sieve material to become damp and to lose efficiency.
  2. If the space that houses your HVO system is enclosed and not sufficiently ventilated, you may not get maximum efficiency from your concentrators. A fresh supply of atmospheric air will ensure that your concentrators receive adequate oxygen to produce a high percentage oxygen gas stream.
  3. If the temperature is too hot (above 90°F / 32.2°C) or too cold (below 40°F / 4.4°C), the concentrators will not operate efficiently. Likewise for humidity: if it is consistently above 90%, you will most likely see a degradation in efficiency over time.

As mentioned earlier, its also important to clean and/or replace the filters on your oxygen concentrators. Most concentrators (such as the M10 shown above) have an external filter, as well as an internal filter. The external filter should be washed and dried every 3-6 months. The internal filter should be replaced every 1-2 years, depending on the dust levels in your setting. It may help to place a sticker on each concentrator with a note about the last filter service.

Get the Power Right

Too often I have learned about electrical issues that could have been prevented if a professional, licensed electrician had been hired. Your HVO system is an expensive piece of equipment, so spending a few extra bucks to get the power right is a smart investment.

3-outlet Relay Box

In the US, Canada, Mexico, and Japan, the HVO Main requires a 120 volt, 15 amp circuit. It will only draw, at peak amperage, about 6 amps, so you may be able power other devices on the same circuit. Be sure that you know what is actually connected to that circuit so that you don’t overload it. It is important to use a power surge protector on the headbox to protect the delicate electronics that it contains in the event of a power spike such as may be caused by a lightning strike.

Each 3-outlet relay box requires a dedicated 20 amp circuit. That’s because each concentrator uses 600 watts, or 5 amps. Thus, three concentrators on one circuit will draw at least 15 amps, possibly a few more at startup. That’s why it’s necessary to have a 20 amp circuit. Nothing else can be plugged into this circuit. Furthermore, you should not use a garden-variety power surge protector on the concentrators or the relay box itself. (If you insist on using one, make sure that it’s rated for the amperage you intend to run through it.) For each 5-outlet relay box, you’ll need a 30 amp circuit. Again, this circuit must be dedicated to powering the concentrators. No other devices should get power on the same circuit.

To summarize the major points on power:

  • Hire a licensed electrician
  • For the headbox, make sure you have 5 amps available, and use a power surge protector
  • For the relay boxes, provision dedicated 20 or 30 amp circuits (as needed) for your relay boxes, but DO NOT use power surge protectors for them.

For 220/230 volt power, the amperage needed is roughly half of the US requirement:

  • The headbox needs 2.5 amps
  • The 3-outlet relay box needs 9 amps
  • The 5-outlet relay box needs 15 amps


HVO systems are robust and can run reliably for long periods of time. To get the best return on your investment, plan your system’s space, power, and ventilation. Make a checklist to ensure that all system components are functioning, and that your maintenance procedures get done regularly. If you need any help with the planning process or have any questions at all, feel free to contact us.

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.