I am going to start by saying controversial that preventative maintenance is NOT always better than breakdown maintenance. The cause of many breakdowns couldn’t have been prevented with routine maintenance. I will say, that a better model is Predictive Maintenance.
In many cases, it doesn’t make sense at all to do PMs from both a cost AND a time perspective. I’ll tell you why, give you some examples, and then I’ll detail out when it actually does make sense to start doing Preventative Maintenance, and why it makes even more sense to move to a predictive maintenance model.
The Preventative Maintenance Model
Example 1: Replace lightbulbs in the women’s bathroom every year
Example 2: HVAC Filter Change every 6 months
Example 3: Lubing chains for a critical piece of equipment every 7 days
You might already be able to tell where I am going with this, but…. There are 3 critical factors in preventative maintenance that you have to consider:
1 - How bad is the worst case scenario?
2 - What is the likelihood of a breakdown?
3 - How much will it cost?
Okay with that being said, let’s look at each of these examples with these 3 questions in mind.
In the 1st example, the worst case scenario is that a bulb could stop working. The bathroom has multiple lights, so worst case, not so bad. The likelihood of a bulb going out at some point is pretty high and the cost to do a PM on these lights every year is quite high given the relative impact it has. With all of that being said, do you think it makes sense to do a PM on bathroom lights? Probably not. Let’s just wait until a bulb goes out and get a call to replace.
In the 3rd example, if there is a breakdown on one of our critical pieces of equipment, that could stop production meaning a loss of thousands, maybe millions of dollars. likelihood of breakdown, probably very high without the proper PMs, and man will that cost a lot if it does breakdown. Probably a good idea to do a PM on that one.
In the 2nd example, probably where most things fall, the worst case is that our HVAC machine goes down. The likelihood of this is questionable. HVAC machines will still run with a clogged filter, but efficiency is reduced causing increased costs and filters have varying life expectancies depending on air quality. Do we PM this HVAC machine? Probably! But we have a few different levers to turn.
How often should we PM? Should we do it every 6 months every 8 months or maybe every 4 months? This is something that is a bit controversial and needs to be looked at from a cost perspective. At the end of the day, PMs can be expensive if you are over PMing something, but can help prevent critical failures. However, we also need to consider the fact that even if we PM something, that doesn’t prevent all failures. We need to make sure we are PMing the right thing and the correct frequency.
At the end of the day, we really want to move from reactive to predictive. As a facility manager, I want to be able to tell when something is close to breaking down, or when the efficiency of that HVAC machine goes down to a point where it makes financial sense to replace the filter. We can do this with a lot of new tools today like digitizing our maintenance and adding meters, and sensors around our facility to track efficiency, temperature, power, etc to give us insight and predict failures before they happen.
Check out UpKeep if you’re looking for a new tool to help you track your maintenance!