Dr-Fix-It! Notebook Archive:
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| Hot Wires . . . I am not sure why my esteemed predecessor (the guy that did this job before me) hot-wired the cooling tower controls. They seemed to be in excellent operating condition, even though they were more than 20 years old. Once I was able to 'undo' the jury-rigging and get the cooling tower controls running again, they worked great! I can imagine a day long ago when a dozen calls came in; almost at once. Maybe, the whole building was getting too warm and the occupants were getting cranky. I can picture the Maintenance Department phone ringing incessantly. People screaming, "It's hot in my office!" "Do something quickly!" And, for whatever reason, hot-wiring the cooling tower controls must have solved the problem.  The cooling tower controls were designed to respond logically to two stages of cooling. On the first call for cooling, the water pumps energize. Six degrees of input higher, the big 30 horsepower vertical blower energizes. Once I completed calibrating the three water sensors, the cooling tower controls staged up and down smoothy. Almost too smoothly . . .It's happened to all of us. All of a sudden 'stuff' hits the fan. It needs to happen now. People are screaming. The boss is mad. There's too much to do and not enough people do it. We all have said, "We will just put a bandage on it to get by for now. We will get back to it later." We have all succumbed to the pressure to just make a temporary fix by saying to ourselves, "When there's more time, we'll get back to do it right". The problem is that we seldom get back to do it right because there always seems to be some other 'stuff' hitting the fan. Good intentioned maintenance people can be the source of many of the problems encountered in a commercial building. The sloppy practices of a maintenance man who is under undo pressure to work a quick fix can easily cost more downtime and money than if the repair was done completely and correctly the first time. A good maintenance manager should work to take the pressure off the technicians. He should be the front line defense to insulate the technicians from the roar of the inconvenienced tenants so that there is enough time and resources to complete repairs properly. A good maintenance manager should never say, "Quick! Just get it working! We will do it right later when there's more time!" I recall once, on a construction job, I needed some electricity. Although a great deal of the electrical work in the building was already completed, the room where I was working did not have any 'hot' outlets. I asked the Chief Electrician if he could make two outlets near my workstation 'hot'. I made the mistake to comment, "Even if it was just a temporary outlet". The Chief Electrician exploded. "NO!", he yelled, "If we can't make it hot permanently, we won't do it! We don't DO temporary!" It was obvious that the Chief Electrician relished giving the "We don't DO temporary!" speech. It was his chance to cherish a moment of self-righteous indignation at my expense. He glared at me in contempt, and continued his tirade, " We don't do temporary work! Temporary work is just redundant labor. We can't get paid for temporary installations. Why would anyone do any installation that they won't get paid for? I have enough work for my men to do. Warranty calls, legitimate charge backs and do-overs cost my company enough as it is! Why would I purposely create do-overs for myself? That's just STUPID! If we can't make it hot permanently, we won't do it! PERIOD! We don't DO temporary!" OK, OK. I got it. But, aside from indignity of having an economics lesson rammed down my throat in public, I appreciated what the Chief Electrician had to say. It is very expensive, both in labor and materials, to perform a quick fix if a second call will be required to make the proper repairs. So, try to avoid quick fixes. Do it right and be done with it. But, there is another reason to avoid quick fixes. Back to the cooling tower . . . With the control circuits repaired, the big 30 horsepower vertical blower ran so infrequently that I became worried that I had set the controls wrong. For a week, I charted the condenser water temperature and the blower operation to confirm the cooling tower was handling the heat load. It was. The tower seldom needed second stage (fan mode) and, when it did, only for a short time. With that, I became worried that the cooling tower's 30 horsepower blower motor would be subject to heavy equipment short-cycling and subsequent overheating so I installed minimum-run duty-timers as well as an anti-short-cycle delay. So, that is the ironic lesson in this story: With the controls working and calibrated properly, that 30 horsepower motor was acutally running too LITTLE for it's own good. That is a pretty far cry from having it operate 24/7 year-in, year-out! Somewhere in the realm of, oh, polar opposite, I'd say. At any rate, that forgotten act of hot-wiring the cooling tower controls - instead of doing the job right - caused a 30 hp motor to run nonstop for several years with an annual energy cost of $14,000. Uncounted costs include the needless wear and tear on the motor and blower. The guy that did this job before me hot-wired the cooling tower controls; probably with the intention of getting back to do the job right when he had a little more time. But he never got back to do it right. And, so, the cooling tower motor just ran and ran. Needlessly consuming $14,000 of electricity every year several years. So, try to avoid quick fixes. Do it right and be done with it. It really is cheaper and easier. Doc 2006.08.20 |
