OK, so the other day I am on-site carrying out a service visit.
Whilst checking out the control cabinet and it's Wiring I noted an aged Hawco Thermostatic controller which was set at about 5 degrees above the coldstore chamber I was recording.
Underneath this was written that the in-store pt100 probe was reading High!
Later on I realised that the condensing unit for this system was permanently on and only went into pump-down when I selected the manual pump-down. Strange!
Is it working? A quick rotation through the temps and Zilch/ Nothing!
So later that day I am reporting to the Engineering Manager and his Senior (Very Experienced) Engineer.
I advise that the control Stat for that particular system was malfunctioning.
Explaining that irrespective of setting the system refused to pump-down.
To which the Senior Engineer laughed and explained that there was a room-stat which controlled the system.
The one that I was looking at was in fact a stat controlling an external beacon.
Which was there to highlight any temperature issue as the store was usually
unmanned. All that I had been doing was to operate the external beacon.
"But no-one advised me there was a problem or responded" I replied.
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