I can safely say that I have never Twitched, nor have I ever been tempted to become a Twitcher. But I will admit to being a bit of a birder, albeit only within the grounds of my estate in Annapolis, where seven bird feeders attract over thirty species of birds over the course of a year. So what exactly is a Twitcher, and should we be wary of them?
Twitching, which Wikipedia defines as “the pursuit of a previously located rare bird” is the preserve of fanatics who’s seemingly sole purpose in life is to seek and locate the rarest of rare birds and then proceed to tick them off a list. This, apparently gives them some sense of greatness in their world, but to most regular birders, Twitchers are frowned upon as being nothing more than inconsiderate glory hunters.
For those with Twitchering aspirations, there is some excellent advice to be found in Sibly’s Bird East book. While browsing this indispensible birders bible the other day, it dawned on me that a large portion of the advice for Twitchers could also be applied when we go hunting elusive Gremlins that are playing havoc with electrical and mechanical systems on board boats. This seems especially relevant for refrigeration and air conditioning, so, using the same advice given for finding rare birds, let’s interpret some points in order to help find those darn marine Gremlins.
1) “Most birders who find rare birds are looking for rare birds.”
Twitchers are actually looking for the unusual. If your mind is honed in to looking only for the obvious and normal, then you may overlook the possibility of something unusual going on. Strange happenings in complicated mechanical systems often occur only under a unique set of circumstances, and Gremlins can be hiding anywhere.
2) “An intimate knowledge of the common species is essential.”
You must have an in-depth knowledge of the system under investigation and its operational characteristics so that you can identify what is normal and what might be the work of a Gremlin. You must have a clear idea of what it should be doing before taking readings, putting a gauge set on, etc., and seeing what it actually is doing. In other words, don’t try and rationalize what you see without first having a clear understanding of what it should look like in normal operation.
3) “Knowing patterns of occurrence improves your chances.”
The boat owner or operator of the system will be a mine of information, so the first thing you should do is talk to them and dig up what you can and sift through it for useful stuff: When? How often? At sea or at the dock? What are the symptoms? Did you fiddle with it? Did anyone else fiddle with it? Did you practice any Gremlin-ridding Juju on board recently? Etc., etc.
4) “Be prepared to defend your identification.”
Are you absolutely, positively definitely sure that your diagnosis is correct, or did you tell the customer that his fridge just needed a whiff of Freon because actually you had no idea what was going on? So when the next guy down the bay finds a loose wire and the system overcharged, are you ready for the call from the customer asking for an explanation and his money back?
5) “Consider alternatives.”
For many anomalies and reports of incorrect operation there is often quite a choice of possible culprits, so don’t go hunting for Gremlins in the obvious places and ignoring the others. What may look like one thing could have several alternative possibilities, and Gremlins come in many shapes, colors, and guises.
6) “Be cautious.”
Gremlins are hiding everywhere. They have long, stretchy legs and can trip you up when you least expect it. Check everything twice or thrice. Are your gauges and meters calibrated and zeroed? Are your test leads making a good non-resistive contact? Is the thru-hull open (that’s a favorite!)? Are you sure that putting refrigerant R409a into a R410a system is OK just because it’s only one itsy-bitsy little digit off?
7) “Be honest.”
And that means being honest both to the customer and to yourself. It’s often tempting to tell your brain to look the other way while you come up with some pokey far-fetched explanation, but it, or a Gremlin, will inevitably come back and bite you.
8) “When mistakes are made, try to learn from them.”
Now, maybe I’m a really slow learner, but I reckon it took me around three years of working on marine refrigeration and air conditioning systems every day before I could walk on a boat and have a good idea of what I was faced with, what it should or should not do, and where Gremlins might be hiding. Mind you, this was back in the late eighties, when clunky holding plate refrigeration systems were the norm and considered to be the ultimate answer. There were plenty of sick systems for me to tinker with, and whole nests of Gremlins were often uncovered in the process. Oh yes, I often made mistakes (my belated apologies to all those affected), but I vowed to learn from them and now try to pass on some of the knowledge gained over 30 years or so, hence these mailings.