The real A/C repair schedule

Oct 4, 2012

My central air conditioner started to suck about a month ago, so I called A/C repair. It took them five appointments, four to assess the problem and one to fix it. The trouble was that for each appointment they’d give me a four-hour window, and every time except the last, they arrived about a half an hour outside the window.

I think they might need to tweak their scheduling system, unless their end game is to set expectations so low that an on-time arrival seems amazing. If that’s the case, well, I slow clap in your direction, A/C repair.

Chart Type Used

Pie Chart

It's everyone's very favorite chart type.


  • Funny as I’m having the same issues with British Gas around my annual central heating boiler service.

    They force you to book a two hour service slot then don’t show and don’t call to say they’ll be late. When they don’t show you have to re-book. I’m hoping tomorrow’s appointment will be “third time’s a charm”! Exact same thing happened last year.

    Glad to see its not just the UK! :)

  • Peter Edstrom October 4, 2012 at 11:17 am

    Service scheduling is an interesting problem space. I did some work at one point trying to find a good system for a sales force. Turns out the size of the timeframe is a great proxy for understanding a multi-variate problem: the size of their staff, the size of typical jobs, and the precision (and thus customer focus) of the appointment, and the seasonal variablilty in the demand.

    If they show up exactly on time, with no window, then they prioritize customer satisfaction first and likely have far more capacity to service than they have demand. This is expensive for the company, but results in high customer satisfaction.

    If they have very wide time windows, then they prioritize economy more than customer satisfaction. They have just enough staff to service the demand and have opted to take a customer-satisfiaction hit when the demand or job durations are higher than normal.

  • You need to get a new A/C guy. The company I’ve used several times shows up, diagnoses, calls for or runs for parts, repairs. One trip. And they show up on time. If you’re getting hit for a trip charge every time they visit, I’d call someone else.

    Unless you only do it for the math. Then, okay.

  • I love this visualization, would love to know what you created it with


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