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I was inspecting a RTU the other day. It was cool and the economizer should have been running but it wasn't. I opened up the compartment and found an Electronic Enthalpy ECONO. I studied it for a little bit then I had one of those Huh,, moments. There in the return air compartment was the Enthalpy sensor and the Return Air sensor mounted up side by side!




  • meplumber
    meplumber Member Posts: 678
    Can't fix stupid can you?

    I got a call from one of my younger techs last spring on a similar issue.  He was scratching his head and spinning in circles.  It took us a bit of tracing wires to find the two sensors both sitting in the return box.

    Good find.
  • Harvey Ramer
    Harvey Ramer Member Posts: 2,217
    No, you certainly can't!

    I just started dabbling in the commercial market. I thought I saw a lot of stupid stuff in residential. I'm afraid commercial is not much better, maybe even worse from where I stand.

    I recently read a report stating that only 1 in 4 economizers installed in the US are still operating properly within 2 years. Not only that but many of them are never properly installed in the first place. This one, for example never opened once in 5 years and still looked brand new. Also Most of the units I'm seeing are turned to the completely lowest setting. I'm turning them up to B setting. I'm going to monitor them to see what the comfort conditions are over this summer.