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Troubleshooting Flowchart for Eureka Central Vacuum

Begin at START and answer each question to diagnose and see a possible solution.

If you are unable to solve your issue or need assistance, call us at 1-800-997-2278 or contact an authorized MD dealer near you.

You can also download a PDF:
Troubleshooting Repair Chart

Notice: This Flowchart is protected by Copyright. It may be used for personal use only and may not be reproduced in ANY form for commercial use without express written consent from M.D. Manufacturing, Inc.

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Reset
Disconnect power unit from pipes. Does the unit alone have good suction?

NO
START at the unit, will it turn on manually? YES Is it always running? NO Does is it have suction at the unit without the hose? YES Is there good suction at the unit with the hose? Is there good suction at all the inlets?

NO

YES

YES

NO
When you turn it on at the unit do you hear a click? Disconnect low voltage wires from unit. Does it still run continuously? Remove inlet. Do low voltage wires leading to inlet start system when touched together? NO Arc across the contact points in the inlet valve neck. Does the power unit start? YES Does the hose have a switch on the handle?

NO

YES
Try another appliance in the outlet. Does it work? Is there good suction at all the inlets? NO Does the system have an electric brush? YES Properly plug hose into inlet. Activate switch on hose handle. Does power unit start?

YES
Does the electric brush turn on when activated by the hose switch? YES Is there good suction at all the inlets?

Central Vacuum Repair & Troubleshooting Solutions

#1 - Electrical failure or short in vacuum head or hose
  1. If the inlet valve contains a 110 volt connection for the power brush, verify it is live. Either test with a voltmeter or plug the power brush cord directly into the inlet. Note: Some electric power brushes require the neck to be tilted prior to activation and will not work in the upright position.
    If the electric power brush activates, the problem is within the hose.
  2. If the electric power brush does not activate, the problem may be within the power brush or within the electric inlet valve(s).
    • Electric Power Brush
      • Check the power brush reset button and, on some central vacuums, the neck-tilt-switch by listening for it to pop out just before the neck goes into the upright position. It may be jammed with debris, such as lint.
      • Check that the roller brush can spin smoothly because the bearings may be jammed with hair or debris.
      • Open the vacuum head and apply power directly to the motor.
        • If it operates correctly for 10 minutes, it is likely not the problem.
        • If it quits, check the service manual for the particular brush or replace the vacuum head, if compatible with your hose and connection wands (vacuum head motors cost nearly as much as a new head).
        • Alternatively, replace the hose, head, and accessories with a new Complete Attachment Kit, compatible with all central vacuum systems.
    • Electric Inlet Valve
      IMPORTANT: Ensure the power is shut off prior to working on the valve or have a qualified electrician make repairs.
      • Check if the valve or electrical inlet is connected through a GFI (Ground Fault Circuit Interrupter) outlet, which may be located in a bathroom. This can easily be reset.
      • Replace inlet(s). See our Replacement Central Vacuum Electric Inlet Valves for information on how to replace the inlet(s) as well as replacement options.
#2 - Clog, not located in system pipes
  1. Check power brush head for a clog by turning it over. Remove wand tube to inspect inside vacuum neck for possible clog.
  2. Check wand tubes by removing and looking through them. A broom handle is handy for removing obstructions.
  3. Check hose for clog by plugging it into a properly flowing wall inlet valve and disconnecting it from any accessory or wand. If there is no suction through the handle, try the following:
    • Insert a long, stiff object, such as a table knife. As you lift the hose, the knife will fall through the hose until it hits the clogged item. Squeeze the hose to grab the knife and use it to break up the item that is stuck. You can also push a garden hose through vac hose, but don't turn water on!
    • If the above does not work, reverse the air flow through the hose by connecting the handle end of the hose to the utility valve on the front of the main power unit. Hold your hand around the connection to make it as air-tight as possible. Alternate suction from the handle end and then the wall end multiple times until the object dislodges.
#3 - Clog, located in central vacuum system pipes or tubes
  1. Isolate the approximate location of the clog by determining the inlet furthest from the vacuum unit that is not suctioning well.
    • Run numbered paper towels or Styrofoam balls through each inlet and check which paper towels/balls made it to the power unit.
  2. Once the location of the clog is located, insert the hose into the wall inlet as usual, hold hand over other end, and let the pressure build up. Quickly release hand and let air rush in. Try this multiple times from various inlets, even those that are close and working properly. This process creates rhythm and movement in the pipes and often dislodges the clog in the central vacuum system pipe.
  3. Lift the inlet valve lid and inspect the first elbow in the wall. Also, inspect the last fitting entering into the vacuum tank and any elbows within the tank. The tank connection should not be glued and it should come loose by wiggling the first fitting. These are common areas for clogs.
  4. Run a Free Flow Maintenance Sheet or paper towel through the clogged inlet valve. This larger bulk item can often dislodge objects by building up pressure and pulling debris through. If the cloth gets stuck, continue to the next method.
  5. Run electrician's fish-tape through the pipe and try to hook object/clog. We do not recommend using a plumber's snake because vacuum pipe has a much thinner wall than plumbing pipe.
  6. Reverse suction backwards through the pipe and inlet valve by connecting a portable vacuum or shop vac directly into the wall valve. Let pressure build, then release. Repeat multiple times. Be sure to allow air to flow backwards without the central vacuum running and remove the central vacuum unit's bucket or top to expose the filtration.
    • Alternatively, the central vacuum tank itself may be used. Remove from wall, set next to wall inlet, plug into electrical, connect hose to tank port or tank intake, put hose handle end into wall inlet, and seal with hand. It may be necessary to suck multiple directions: toward the unit, then toward the inlet, then towards the unit again to loosen the object.
    • Whichever machine you use, also try placing a Free Flow Maintenance Sheet or paper towel inside the pipe where it enters the main canister and then try sucking it back toward the inlet to catch the object in the air pathway.
  7. Consider any recent construction or other work where someone may have driven a nail into a pipe (especially closet organizers, phones, alarms, or recent pictures hung).
  8. If the clog will not dislodge, then find its exact location by one of several ways:
    1. Run paper towel through and listen for humming or vibration.
    2. Create louder noise using a ping-pong ball. Insert into inlet, turn on unit, then remove inlet to get ball in.
    3. Endoscopy cameras can be attached to an electrician's fish-tape to view the interior of the pipe.
    Once the exact location is found, cut the pipe and pull out the clog. Use a coupling to easily put the pipe back together.
  9. Important: Once the clog is removed, verify by running a Free Flow Maintenance Sheet through each inlet. If they don't all show up, do it again with numbers on each to determine which valve is clogged. The clog may have migrated to another section of pipe that is out of the air pathway.
  10. Pipes that run underground can sometimes coagulate with debris from moisture. Proper underground installation installs the central vac pipe inside three-inch irrigation pipe. Run 10 pounds of rice through system into the unit, repeat. If ineffective, trench old lines and replace.
  11. In rare cases, the old vacuum pipe might need to be abandoned and a new pipe run from a working section to the valve location.
  12. If the suction remains poor, you will need to replace/install new pipe & fittings. Contact a local MD authorized dealer for assistance.
NOTE: Proper installation of a central vacuum virtually guarantees no clogging. Large objects should get stuck at the first elbow just behind the wall valve which is designed to catch items. A sloppy installation can create opportunities for debris to catch over time. Specific installation errors include Tee's that are installed backwards, pipes rough-cut with a hacksaw, excessive elbows, and pipes not fully inserted into the cuffs of the fittings. Many times, the build-up will eventually get large enough to break way but in rare instances, the clog remains.
#4 Bad inlet valve
  1. The low voltage connection is no longer reaching the contacts that touch the hose when inserted.
  2. Watch the Inlet Valve Installation Video for tips and help.
  3. If replacement inlet valves leak air when another valve is being used, place electrical tape on the neck of the valve prior to insertion to form a better gasket.
WARNING: Some inlet valves contain 110 volt electricity. Electrical power to the valve should be turned off prior to working on them or a professional electrician should be hired to make repairs.
#5 - Low voltage wire cut or junction pulled apart
  1. Inspect for wire damage or breaks at locations possibly affected by things such as recent construction, digging, pests (rats or mice), or even just someone tripping over wire in your attic.
  2. If you find the break, re-splice broken wire (coppers together and tins together).
  3. Wires could be disconnected at the main unit. There is no polarity, so wires can go back into either connection.
  4. Can't find the break? Options are as follows:
    1. Re-route wire from central vacuum unit or any working inlet to the compromised section of wire or run a whole new wire between the unit and inlet. Buy central vacuum wire.
    2. Add a remote control clicker and receiver to the system. It's easy and convenient.
WARNING: Electrical power should be turned off prior to working on installed wires or a professional electrician should be hired to make repairs.
#6 - There is a clog in the hose
  1. Check central vacuum hose for clog by plugging it into the utility valve on the front of the unit or a properly flowing wall inlet valve. Disconnect it from any accessory or wand.
    • If no suction is present through the handle, then insert a long stiff object, such as a table knife. As you lift the hose, the knife will fall through the hose until it hits the clogged item. Squeeze the hose to grab the knife and use it to break up the item that is stuck. You can also push a garden hose through vac hose, but don't turn water on!
  2. Also, try removing the clog by reversing the air flow through the hose. This is done by connecting the handle end of the hose to the utility valve on the front of the main power unit. Hold your hand around the connection to make it as air-tight as possible. Alternate suction from the handle end and then the wall end multiple times until the object dislodges.
#7 Unit is good, pipes have leaks
  1. Consider any recent work done on the house, such as construction, wires/cables ran near where the pipe is installed, paneling, or even just hanging a picture. Turn unit on and walk around house listening for a leak, starting in these areas. The air should sound louder and higher pitched where there is a leak.
  2. Verify all vacuum inlets are installed correctly and none of their doors are broken. This includes unused inlets or those tucked out of sight. There may also be inlet valves plastered over, which will require looking down the walls from the attic to find. See our Central Vacuum Inlets page for a video guide on how to replace your broken inlets and to order replacements.
  3. For central vac inlets installed in floor, check for fallen or loose pipe.
  4. If the central vacuum power unit has insulation in the filter bag or debris receptacle, then the break is most likely in the attic.
  5. If any central vacuum system pipe runs underground, check for damage from recent gardening or tree roots.
  6. Broken/damaged pipe will need to be replaced. You can order the right pipe from us. Contact a local MD authorized dealer for help.
#8 - The Power unit has bad suction
  1. Ensure all vacuum motors in the power unit are working. Note that some units have more than motor. If a motor is not working, see our genuine Lamb Ametek vacuum motors page for help in identifying, ordering, and replacing the motor.
  2. Check central vac power unit gaskets and for cracks in housing.
  3. Verify the correct voltage is going to power unit. There should be a compliance label on the unit specifying the proper voltage, among other details, such as model and serial numbers.
  4. Check for loose wires and a loose motor. Tighten as needed.
  5. Ensure the mini-breaker functions correctly.
  6. On a cyclonic power unit, check for the following:
    1. Lint and debris in motor fan blades.
    2. Lint and debris on screen on intake.
    3. Too much back-pressure from exhaust line.
    4. If you are unsure whether your central vacuum is cyclonic, please read our Central Vacuum Filtration Education article for guidance or contact our Customer Care Team or a local Central Vacuum Dealer for assistance.
  7. On a bag type power unit, check for fine plaster dust clogging the primary or secondary filter.
  8. If the exhaust is vented, check the exhaust cover for blockage and clear if needed.
  9. For bagless, bottom-emptying central vacuums units, be sure to reach up into the vacuum unit to find a filter or screen that needs to be cleaned, replaced, or scraped off.
#9 - Short in power unit
  1. If your unit has a manual on/off switch, disconnect the low voltage leads from the switch. If the unit stops running, the switch needs to be replaced.
  2. The relay has failed and needs to be replaced.
  3. On older units with the transformer and relay separated, the relay needs to be replaced. See our Relays & Transformers page to find the replacement part you need.
WARNING: Be sure to unplug the central vacuum power unit prior to replacing electrical parts or contact a local MD authorized dealer to schedule repairs.
#10 - Short in low voltage system
  1. Inspect for wire damage or breaks at locations possibly affected by things such as recent construction, digging, pests (rats or mice), or even just someone tripping over wire in your attic.
  2. Disconnect any splices you can find and check continuity of short.
  3. Worst case: re-route wire from any other working inlet or wire (possibly running wire behind baseboards, under carpet in a protective sleeve, in closets, or in air ducts).
  4. Another option is to abandon the low voltage wires and use a remote key fob for unit activation.
WARNING: Electrical power should be turned off prior to working on installed wires or a professional electrician should be hired to make repairs.
#11 - Dead motor: relay is getting power, but vacuum motor is not turning on
  1. In 99% of cases, the motor is bad and needs to be replaced. Please see our Central Vacuum Motors page to find a replacement motor for your unit along with general motor replacement instructions.
  2. If there is a mini-breaker popped out over an inch, push it in and try activating the central vacuum unit. If the unit runs for a few minutes then shuts off, the motor needs to be replaced.
  3. Central vacuum motors generally last for 800-1100 working hours. If your motor has run less than 800 hours or activates by jolting the canister, it may be possible to extend the life of the motor by replacing the carbon motor brushes.
  4. Go to our Troubleshooting the Motor, Relay, Transformer, Motor Brushes, & Circuit Board page for more information.
WARNING: Be sure to unplug the central vacuum power unit prior to replacing a motor or contact a local MD authorized dealer to schedule repairs.
#12 - The power unit is not getting electricity
  1. Check house circuit breaker.
  2. Verify that the central vacuum is on a dedicated circuit and can support the proper amperage.
  3. Plug the vacuum into another outlet. If it activates properly, then the underlying issue is within the house wiring.
  4. If the issue cannot be resolved, please contact a Central Vacuum Dealer or an electrician.
  5. Go to our Troubleshooting the Motor, Relay, Transformer, Motor Brushes, & Circuit Board page for more information.
#13 - Transformer and motor not getting power
  1. Inspect the power cord for damages. Try testing using another cord with the same specifications (voltage, amperage, etc. will be printed on the cord).
  2. For units with circuit boards, the transformer and relay are located on the same board. Identify the proper circuit board by going to our Parts for Eureka page.
  3. Bad transformer - check for spark between the two low-voltage wires out of transformer.
  4. Bad relay - check points, arc across to see if it solves it.
  5. Check out our Troubleshooting the Motor, Relay, Transformer, Motor Brushes, & Circuit Board page for more step by step guides.
WARNING: Be sure to unplug the central vacuum power unit prior to replacing electrical parts or contact a local MD authorized dealer to schedule repairs.
#14 - Low voltage in hose is not working
  1. Ensure hose is full inserted into inlet valve.
  2. Flip hose switch on and off. If the switch feels flimsy or weak, it needs to be replaced. Please see our replacement hose switch options for industry-standard replacements.
  3. Disconnect hose from inlet valve and take apart the hose handle. Clean off any lint or debris located on copper rings or contact points.
  4. Test low voltage wiring within the hose by watching our Central Vacuum Hose Troubleshooting Video for further instructions.
  5. If the issue cannot be resolved, the hose may need to replaced. Please see our central vacuum hoses for industry-standard replacements.

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Free Flow Wipes

Free Flow Wipes

Free Flow Sheets clear the inside of the hose and pipes as they travel to the vacuum unit.