Tech expert tears down McDonald's McFlurry machine to explain why they always break

We've all had that moment of disappointment when arriving at McDonald's.

It's a hot day, blistering in fact, and the one thing that would cool you down properly is a delicious McFlurry from McDonald's. Nothing else will do, so off you pop to the nearest outlet and get in the queue.

Then, your heart sinks as you behold the McFlurry machine, only to see the dreaded felt-tip note sellotaped to it bearing the pronouncement of doom: 'OUT OF ORDER'.

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It turns out there is, in fact, around a one in four chance of this happening in the US as well, and often it's not even a mechanical problem.

The McFlurry machine is actually a variation of a soft serve machine, like Mr Whippy, with the catchy name of 'Taylor C709 Soft Serve Freezer'.

In purely mechanical terms, it's a relatively simple piece of equipment.

The inside contains a compressor, as well as a motor which mixes up the ice cream.

Most of the time when it does break down, it's because the machine has overheated - and on a purely mechanical level, would be fine just being left to cool so it could get back to serving up frozen treats.

So, what's the problem?

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The problem is the software which is attached to the machine, the computer part of the equipment. While the machine is mechanically okay, the error message that flashes up means that only a technician from the manufacturer, Taylor, can come and get the machine up and running again.

Without the technician the error code can't be cleared and there will be no more ice cream. And the cost for the franchise owner? $315 for 15 minutes of repair services.

iFixit Teardown Tech Shahram Mokhtari said in a video on the topic: “This ice cream machine is not a complicated piece of equipment, but the downtime that it suffers is well in excess of what’s acceptable for industrial equipment.

“Twenty-five percent of Taylor’s profits come from service technician call out charges. That’s not surprising given that the service techs charge $315 per fifteen minutes of the callout."

He added: "The error codes are nonsensical, counterintuitive, and seemingly random, even if you spent hours reading the manual.”

The bizarre scenario of people and businesses not being allowed to fix their own devices is down one piece of legislation: the Digital Millennium Copyright Act 1998.

This legislation effectively allows companies to 'lock' their products and make sure that people have to pay for an official technician to fix it.

Although the right-to-repair movement is on the rise here in the US, so hopefully a much brighter future is in store for the beloved McFlurry.

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