What Are the 5 Signs of Vacuum Pump Failure?

Posted by Paul Dabrowski on Nov 24, 2021 10:00:00 AM

Even the most well-constructed vacuum pump can fail after extended use. In industrial applications, for instance, the downtime resulting from pump failures can be prohibitively expensive — especially if it forces production to grind to a halt. 

As vacuum pumps are found in everyday technology, consumers are also impacted by pump failure. The rattling sound of a failing car engine pump, for example, illustrates that your car engine needs repairs. 

Knowing the signs of vacuum pump failure is crucial in maintaining a functioning system and avoiding dangerous or expensive issues resulting from failure — like being stranded after having car engine issues or missing shipments when your production line halts. Here, we unpack five of the most common signs of vacuum pump malfunction. But first, let’s explore why maintenance schedules are key in avoiding vacuum pump failure. 

maintenance schedules and clues from a failing vacuum pump

When a vacuum pump fails, it rarely occurs without warning.

But it can be challenging to know what an optimally functioning vacuum pump looks like. This is because vacuums are almost always incorporated into larger systems while being used for varied-use cases. As a small part of a larger system, it’s also difficult to assess when pump maintenance is needed until production is affected. 

Despite this, proper maintenance is required to identify when vacuum pumps are near to failing. Without maintenance, you risk being caught off guard by unexpected downtime and the cost of repairing or replacing a pump. Creating a maintenance plan helps you avoid pump failure and ensures you fix system leaks before any issues or telltale signs arise. These plans should be guided by the owner’s manual, the project environment and the material being pumped. 

Your maintenance plan should allow for the servicing, repair and replacement of pumps. For smaller projects, this may involve sending pumps back to the manufacturer. With this in mind, here are the common signs of a failing vacuum pump:



When your vacuum pump exhibits loud or atypical noise, then it may be close to failure. Throughout their use, ageing and accumulated wear cause a specific part in the pump to fail. Increased noise is often a sign that a pump requires maintenance and cleaning. While parts like diaphragms, valve plates and seals are easily replaced, increased bearing, motor or air noises may indicate that more extensive repairs are needed.


If dirt or other contaminants enters the vacuum pump chamber or valves, overall pump performance can be impacted. When pumps need more time to accomplish operations, they may be in danger of failing. 

At this point, thoroughly cleaning your pump and ensuring that no contaminants reach other parts is a necessity. Without this step, these contaminants will continue affecting pumps, leading to more maintenance or repairs. Filters are also valuable in preventing contaminants from entering your system.



It can be difficult to diagnose vacuum pump failures resulting from heat buildup. Factors may include having a bad motor, incompatible pump applications or poor ventilation. Constant overheating may indicate a malfunction. 

When troubleshooting for an overheating pump, first assess the pump ventilation openings. If these openings are blocked or are too close to another object, fixing this issue may be as easy as resituating the pump.


If a pump won't turn on, it may be a fuse issue. First, check if the pump’s fuses are blown. If your pump works and there are no issues after you’ve replaced the fuses, then you’ve fixed the problem.   

But if blown fuses are a continuous problem, then you may have a power issue — or you’re using a voltage that is too high for your pump.


Blockages or flow restrictions at the inlet or outlet cause vacuum pumps to start slowly. If there are no blockages, your pump might have a damaged or weak motor or capacitor. 

This could be the result of an improper application, especially if there's an inlet vacuum or added pressure at the outlet, which will need to be addressed. When a vacuum pump fails here, fuses can overheat and burn out, eventually leading to damage of the motor or start capacitor.


Establishing a regular maintenance schedule is key to preventing vacuum failures before they occur. Another step to preventing failure is to look out for the five signs shared above. 

But preventing vacuum failure is only one step in maintaining a safe and reliable vacuum system. We’ve written a free ebook to help organisations troubleshoot vacuum system issues and optimise vacuum system performance. In it, we share insights on:

  • The causes of slow evacuation time
  • How to increase ultimate pressure of the vacuum pump
  • How to deal with troublesome vacuum pumps and gauges
  • How to deal with ambient conditions such as temperature, magnetic fields and ionizing radiation

Click on the link below to grab your copy:




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Vacuum Pumps