It’s a common question that doesn’t come with a straightforward answer. Our customers make a significant investment in instrumentation, so if something can be repaired, it’s usually easier to get past the budget department. But there are several factors to consider first.
- How does the repair cost compare to a new unit? Some repair costs, especially on older out-of-warranty equipment, are considerable. And some replacements, with their newer technology, have a lower purchase price than the original. Even after repair, older instruments have a high probability of failing again, just due to age.
So if the repair costs approach 60% of the cost of a new model, is it worth the risk? New instruments come with the latest technologies and brand new warranties, so aside from the purchase price, it’s worth examining what you’ll get by buying new.
- Are repair parts available? If the instrument is out of production, there’s a likelihood that the repair parts aren’t being manufactured either. So, even if you send the unit out for repair, it may not be possible, because the parts for the repair aren’t available..
- Beware the Test Bed Conundrum. So, you have an instrument installed, and it’s not behaving as you expect, so you send it in for repair. First, the technician runs a set of diagnostics on their test workbench. But, the tests aren’t run with the same conditions as in your process, with the same wiring, connected to the same other devices. They’re run in a “clean” environment, no noise or interference, new wiring.
So, if the tech can’t make the instrument fail the same way it does in your application, they can’t fix it. (And, frankly, there are some errors a bench test just can’t diagnose.) No repeatable failure means no repair. They send it back saying, “There’s no problem here.” But it still doesn’t work for you. In the meantime, you’ve had to put in a spare or a work-around. At that point, why not just upgrade?.
- Why repair obsolete technology? Here’s a prime example. The V5 version of Honeywell’s paperless recorders came standard with floppy drives for storing data. Those drives, even in the best conditions, fail on a regular basis, and their storage space was limited. Replacement drives didn’t always help the situation. The next generation of paperless recorders came with flash memory, a far more reliable technology, especially considering that the main function of a recorder is to save data.
Consider the ultimate use of your instrument before you decide to repair. If there’s a better technology at play in the new version, and it improves your results, you may want to make the switch, even if the replacement cost isn’t significant.
- How long does it take to get a repaired instrument back into your process? Getting a repaired instrument into operation isn’t too different from starting up a new one. When technicians do troubleshooting and repairs, they wipe out any custom configuration and return it to the factory out-of-the-box setup. So, your custom configurations, parameters, alarms, special options, saved data, are all gone. Repaired or new, you still have to commission the instrument to get it operational.
- Don’t forget associated costs when comparing repair vs. replacement. A repair involves removal from service, shipment there and back, turnaround time, and re-commissioning to a working state. Sometimes, those combined costs escalate to a point where replacement with a new unit actually costs less than the repair.
So, do I suggest replacement over repair? Sometimes. It all depends on your current investment, what the repair entails, and whether the new device will give you a significant improvement in your results. But I hope this list gives you a good basis for your decision.
Oh… back to #5. If you pay attention to nothing else you’ve read here today, check this out. Before you send an instrument out for repair (or ideally, whenever you install a device into your process), there’s a critical step you shouldn’t miss. Read my very first blog post: “Save your custom configuration! Avoid the headaches!“
Lesman Tech Tips 