Preventive vs. Predictive Maintenance: What’s the Difference?

While no one can predict the future with 100 percent certainty, nor can they prevent the inevitable, prediction and prevention are actually achievable in the maintenance world.

Both preventive and predictive maintenance are types of proactive maintenance, but they differ in implementation. Preventive maintenance is regularly scheduled — think cleaning HVAC filters or replacing coolants after a period of heavy usage.

In contrast, predictive maintenance uses condition-based monitoring technologies to track equipment and determine when maintenance is needed. For instance, let’s say a temperature sensor on an AC vent identifies that the air is coming through warmer than usual, requiring the system to work harder and longer to achieve the intended building temperature. To avoid a full breakdown, a work order would typically be created to inspect the HVAC system and to possibly perform maintenance.

While the two maintenance strategies are both part of a larger maintenance program, one involves performing maintenance on a routine schedule, and the other requires maintenance once a monitor indicates a shift in an asset’s operational efficiency. Let’s break down the differences between preventive versus predictive maintenance strategies to help you determine which one works best for your business.

Understanding Preventive Maintenance 

Preventive maintenance is the strategy of performing scheduled maintenance tasks before a specific problem has been identified. Typically, preventive maintenance occurs on a time-based or usage-based schedule.

For example, preventive maintenance could involve daily or weekly cleanings of restaurant equipment to prevent larger problems from occurring, like grease build-ups in an air fryers that could lead to underperformance or even fires. Preventive maintenance can also be based on usage, such as how cars get oil changes after a specific number of miles. In a factory, preventive maintenance might involve forklift maintenance after the machine runs for a certain number of hours, or a conveyor belt might be proactively replaced after a certain amount of units have been produced.

To determine preventive maintenance schedules, companies often rely on a mix of best practices — such as equipment manufacturer recommendations — along with historical data that could indicate future maintenance needs.

Pros & Cons of Preventive Maintenance 

Preventive maintenance can be a great way to avoid potential problems, but it does have some possible drawbacks or challenges to consider. Some of the top pros and cons of preventive maintenance include the following:

Pros

• Proactive: Preventive maintenance is proactive, meaning you’re getting in front of potential problems, rather than having to react to them. This helps avoid emergency maintenance situations in which you’re scrambling to find replacement parts or schedule maintenance work outside of normal business hours — wasting time and money.
• Increases equipment reliability and lifespan: Being proactive also means you can increase equipment reliability and lifespan. Cleaning on a regular basis, for example, helps avoid clogs or grime build-up that can deteriorate motors or other parts. 
• Reduces unplanned downtime: With reliability also comes the advantage of reducing unplanned downtime. By preventing equipment breakdowns, you can avoid situations in which your company is unable to operate as intended. Inspecting gym equipment on a regular basis, for example, can help health clubs avoid having to close machines for repairs, which can harm customer experience. 
• Decreases unplanned maintenance costs: Unplanned downtime can also lead to unplanned maintenance costs, especially if you have to pay extra for expedited repairs. Instead, preventive maintenance can be proactively budgeted for. 

Cons

• Involves more parts inventory management: Companies usually have to maintain a larger parts inventory in order to be able to replace parts proactively.
• Requires planned downtime: Most preventive maintenance work requires the asset to be nonoperational. Even though the downtime is planned, it’s still not ideal if it affects operations.
• Maintenance is performed even if there’s no issue: Preventive maintenance is typically done when there’s no apparent problem — i.e., replacing parts after a certain number of uses. Some businesses might find that the time and money required to do preventive maintenance outweigh a more reactive approach to maintenance. 
• Increases planned maintenance costs: Although you can reduce unplanned maintenance costs, there’s still the expense associated with planned maintenance, such as having enough staff to conduct regular inspections and cleaning.

Understanding Predictive Maintenance 

Predictive maintenance — an extension of condition-based maintenance — is a strategy that involves monitoring asset performance to predict problems and fix them before a larger issue develops. 

Usually, this monitoring is achieved through Internet of Things (IoT) technologies, internet-connected sensors or devices that track asset metrics like temperature and vibrations. That data is tracked via a system such as a computerized maintenance management system (CMMS) software, where maintenance teams can monitor equipment in real time. If there seems to be a problem — say, if the IoT device picks up that a machine is vibrating more than normal — then a work order can be scheduled to make a repair or replace parts, rather than waiting until there’s a breakdown. The data is also analyzed via machine learning software that can identify equipment health and spot possible problems that are developing or are at risk for soon developing. 

Pros & Cons of Predictive Maintenance 

Predictive maintenance might seem like magic, but there are some pitfalls to be aware of too.

Pros 

• Proactive: Like preventive maintenance, predictive maintenance is proactive. You’re getting in front of problems before they cause full equipment failures.
• Addresses real issues: Sometimes, preventive maintenance may seem overly cautious in that you’re replacing parts even though nothing is wrong yet. In contrast, predictive maintenance addresses real issues, such as noticing that a refrigerator is having trouble maintaining a constant temperature. 
• Less downtime required than preventive maintenance: Because predictive maintenance involves monitoring equipment health in real time, there’s typically less downtime required than preventive maintenance. You’re only performing maintenance when there’s a suspected problem, not when a certain amount of time has passed or uses have occurred.
• Fewer parts inventory required: Addressing real issues as they occur also requires a smaller inventory of replacement parts. Perhaps instead of having two backups of every part — one for the next scheduled replacement and one as an emergency backup — you might only have one backup for times when predictive maintenance technologies suggest parts need to be replaced. 

Cons 

• More complex than preventive maintenance: Predictive maintenance is more complex because it involves more technologies and analysis, rather than just following a set schedule.
• Downtime is shorter, but it’s considered unplanned: Although you might have less equipment downtime since you’re not conducting maintenance on a set schedule, you don’t know when that downtime will occur. 
• Requires more expensive equipment and technologies to collect data: Installing IoT devices and machine learning software adds cost. These might save you money in the long run by avoiding emergency maintenance, for example, but there are still upfront expenses you need to account for.
• May require maintenance team training: The technology behind predictive maintenance can also come with a learning curve, and you may need to train your maintenance team on how to monitor this data and perform maintenance tasks before the problem festers. 

When to Use Preventive vs. Predictive Maintenance 

Both preventive and predictive maintenance have their pros and cons, and sometimes, it makes sense to use one over the other.

For companies getting started on a more proactive maintenance strategy, preventive maintenance often makes more sense as a first step. That way, you don’t have to invest in new technologies like IoT devices right away, and you can have more clarity over planned downtime and maintenance costs. Companies that already have a robust preventive maintenance strategy in place might then move onto predictive maintenance, especially those that have the budget for predictive technologies and can invest in training maintenance staff on how to use these tools.

That said, you don’t necessarily have to choose one over the other. You can use a blend of preventive and predictive maintenance strategies, such as by having fixed cleaning and inspection schedules for preventive maintenance, while also monitoring equipment performance in real time to predict breakdowns in between inspections. For example, you might replace AC coolants on a set schedule while also monitoring HVAC system vibrations to potentially spot issues with the motor before it breaks down.

How a CMMS Software Helps With Both Maintenance Strategies 

Using CMMS software like Coast can help when it comes to implementing both preventive and predictive maintenance strategies. Key benefits of using a CMMS include:

• Asset management: Maintain a real-time asset inventory and asset history, which can be helpful for seeing what work has been done in the past and what needs to be scheduled.
• Maintenance scheduling: Create a preventive maintenance schedule that alerts maintenance technicians when work orders are due on a set schedule — whether it be daily, weekly, monthly or even annually.
• Reporting and analytics: Analyze asset performance and condition-based monitoring in real time, and then review reports in areas like work order history and inventory management to ensure your team is following through on maintenance tasks and is prepared for future ones.

See for yourself how Coast’s CMMS can help you easily manage preventive and predictive maintenance. Sign up for a free account today.