Troubleshooting & Support

Quick Check <— Do this first

Symptom: The system is not turning on or some components are turning on but others are not.

IMPORTANT: Pay special attention to #1 below. YOU MAY NOT HAVE A PROBLEM AT ALL. It’s worth checking.

  1. Is the system off because the pressure in the tank is above the low setpoint? What is the tank pressure right now? If the pressure is above the low setpoint (greater than 30 PSI for the Standard, greater than 100 PSI for the Mighty Mite and MAX), the compressor will NOT turn on until the pressure falls BELOW the low setpoint. This is a safety mechanism that prevents the compressor from straining against high tank pressure during startup. In this case, use oxygen. Eventually the pressure will drop below the low setpoint and the system will turn on.

  2. Is the system plugged in and powered on? Check the circuit breaker panel for tripped breakers. Recent models (since October 2018) have a green LED on the circuit board. To see it, you must open the lid of the headbox. If the LED is lit, the headbox has power. Are the oxygen concentrators getting power? Read on.

  3. Are the coaxial cables attached to the right components and hand-tightened? There should be a coaxial cable running from the headbox to the relay box. If you have multiple relay boxes, you can daisy-chain the signal from one relay box to the next using the second coaxial connector. If you have a drone, you’ll also need a cable running from a relay box to the drone’s coaxial connector.
    NOTE: The coaxial cable(s) should only be hand-tightened, but firmly attached. You can use a wrench but be very gentle — over-tightening can strip the threads. If tightening doesn’t help, you may want to try a new coaxial cable.

  4. Do you have sufficient power? Each headbox (Master and Drone) requires a dedicated 15 amp circuit. Each 3-relay box requires a dedicated 20 amp circuit. Each 5-relay box requires a dedicated 30 amp circuit. If the circuits are not dedicated, other non-HVO devices may be using power and reducing the available amperage.

Symptom: Oxygen purity is lower than normal or system not filling as fast as normal

  1. Are the brass manifold connectors seated correctly and hand-tightened? Poorly seated fittings can allow air to be drawn in which can dilute the purity of stored oxygen.

  2. Are all of your oxygen concentrators turned on? Check the power switch on each concentrator. Look for warning lights. Check your circuit breaker panel for tripped breakers.

  3. Are there any line leaks? Check all oxygen line fittings (barbed fittings, push-to-connect fittings, manifold plugs) to ensure that they are firmly connected. Gently check to see that the brass fittings are seated correctly on the barbs of the oxygen concentrators.

Support Procedure

We understand the urgency of your issue. To make the support process safe, responsive, and efficient, we need information from you. Please provide the following:

  1. Photos of the inside of the Master headbox. You must remove the three Phillips-head screws from the lid. Open the lid and take 2-3 pictures of the inside of the headbox. We need to see the logic board, compressor assembly, and compressor dump-valve. If there are other photos that may be useful, please take those, as well.

    DANGER: Do not reach into the headbox when the system is plugged into live power.

  2. Any notes about what you’ve tried. Be sure to go through the Diagnostic Procedure below BEFORE contacting us.

  3. Send an email with photos attached to and include the following:

    • A subject line that states “HVO ISSUE at <your business>”.

    • A description of the problem.

    • Your name, phone number, and the time that the problem was first observed.

    • If there were any recent events that may be relevant (lightning storm, power outage) please mention these, as well.

  4. For urgent issues, you may text +1 (402) 990-6143. An urgent issue is defined as an HVO-related problem that is causing a significant loss of productivity or an outage. We do not provide 24x7 support, but we will go out of our way to help you as quickly as possible.

Diagnostic Procedure

Go through each of the following steps BEFORE you call for service:

  1. Check for tripped circuit breakers. Check that every outlet that you are using works properly. To test, plug a working tool like a hand drill or a lamp into each outlet. If you have a voltmeter, you can use that.

  2. Check the connections to all your coaxial cables. If the cables seem worn or have an intermittent connection, replace with new coax cables. When the system is running use a voltmeter to see if 24v DC power is running through the cable. If you don’t have a voltmeter, you may want to visit the hardware store and get a cheap one. It’s important to have one for quick problem solving, and it can be difficult to solve tricky problems without one.

  3. Check the oxygen concentrators. Unplug the concentrator from the relay box and unscrew the brass fitting to the manifold. One at a time, plug the concentrator directly into a working wall outlet (you can use an extension cord for this).

  4. Check oxygen flow using the flow meter on the oxygen concentrator. This assumes that you have a flow meter. If you don’t, you may want to invest in one. Verify that each of the concentrators is producing an adequate flow of oxygen. Does the lpm rise or fall as you turn the knob on the flowmeter?

  5. Check oxygen purity. If you have an oxygen purity tester, measure the output of each oxygen concentrator. (HVO has Ultrasonic Oxygen Purity Testers for sale, if you would like to purchase one.)

  6. Verify relay box power. One at a time, test each relay box separately by running a (tested, known-to-be-working) coax cable directly from the master to one relay box at a time and turn on the master. Note that the tank pressure must be below the low setpoint for this to work. If necessary, release some oxygen from the tank so that the master turns on.

  7. Check the dump valve assembly. If the compressor is running and you can feel air coming out of the clear line under the headbox, this means that the dump valve isn’t closing. A new dump valve may be needed.

  8. Test the Drone. Run a working coax cable directly from the master to the drone. Make sure the drone switch is in the “on” position, the cable is fully tightened, and the cord is snug in the back. Plug the drone directly into a free outlet separate from the master. Disconnect the oxygen inlet hose on the back of the drone and check for a vacuum. Listen to determine if the drone compressor is coming on. If it’s humming but not coming on (no vacuum) turn it off immediately and call service.

  9. When you reconnect the system, check all cords, cables, and connections. Power cords and cables can come loose over time from vibration. Coax cables can jam and seem fully tightened when they’re still loose. Wiggle the screw connector and keep trying to move the nut until it is tight (tighten only by hand).

  10. Eliminate non-functional components. Pull out any non-functional concentrators and/or relay boxes. You can often assemble a temporary system with the working components while others are being serviced.

WARNING: Never operate the HVO system with the oxygen concentrators powered off but still connected to the manifold unless the flow valves are turned all the way to zero. Running atmospheric air through concentrators that are powered off could cause permanent damage to the sieve beds. The best practice is to disconnect the oxygen line from each non-functional concentrator and plug the hole in the manifold where they were removed.

Possible installation issues:

  1. Building wiring problems:

    • Power fluctuations or shared circuits with insufficient power

    • Sometimes a lightning strike can cause blown circuits. The HVO circuits should reset but some concentrators have external pop off fuses that need to be reset.

    • Trying to run your system off of a generator that doesn’t produce enough power

  2. Insufficient ventilation of heat and / or nitrogen. Nitrogen build-up will cause low oxygen purity in a closed space as the available o2 in the air is depleted. The cure is to install additional ventilation. You can plug a fan into an available outlet on the relay box to circulate air when the system turns on.

  3. Ambient temperature is above or below what is recommended for PSA oxygen concentrators. Practically all models operate best between 45 - 90℉, with humidity below 85%.

Low oxygen purity can be caused by:

  1. Concentrator flow rate dialed too high

    • Flow meters should be dialed to just below the top flow rate. For example, a 10 lpm oxygen concentrator should be dialed back to 9-9.5 lpm.

  2. Power isn’t reaching oxygen concentrators:

    • Not all concentrators are plugged in

    • Relay box or circuit-breaker tripped

  3. Leak in the manifold. Check all the oxygen lines.

    • Check that the brass fitting is securely seated on the barb of the oxygen concentrator. Hand tighten fittings, do not use tools on the brass fittings connected to the barbs of the oxygen concentrators.

    • Check the manifold lines at the push to connect fittings. If necessary, cut off the ends of the lines to make a flush cut, and re-insert into push to connect manifold or connection.

  4. Some concentrators, such as Integra Sequel, occasionally don’t turn back on even though the relay box is calling for power.

    • Plug your concentrator directly into the wall and turn it on. Disconnect power cord, wait 10 seconds and plug it back in. If the concentrator does not power back on, it may not work well with the HVO System.

Note that a non-functioning Drone can be temporarily left in place. Disconnect the oxygen input hose in the back and make sure all the o2 being generated is attached to the master or other working drones.