Is it time to change your mechanical relays?
It seems like every November we get the same phone calls and the same e-mails... "My kiln has stopped working and I have a show this weekend. Please HELP!" With that in mind, it's important to remember... owning a kiln is like being a Boy Scout, it's important to always BE PREPARED!
Murphy's law says that whenever you need your kiln most and are firing the most, that's just when it's going to have a problem. So.... we all know that an ounce of prevention is worth a pound of I told you so. This is not directed to any one of our clients who've contacted us this month with an OMG moment! This is for all of us, who are just very busy and forget to take care of the basics. And yes... this has happened to me so, you're not alone.
If you don’t already know, a relay is the part of the kiln that controls the power or current to the element, allowing the element to either receive current and get hot, or to interrupt the circuit thus not allowing the element to receive current and cool down. The mechanical relays, which come standard on most kilns, are what is responsible for the ubiquitous opening and closing clicking we hear while our kilns run.
ALL MECHANICAL RELAYS in U.S. kilns are virtually the same... no matter the manufacturer.
Mechanical kiln relays have a life of up to “X” amount of clicks and then they fail. This failure can either be in the closed position (Yikes, my kiln temperature keeps rising and it won’t turn off… everything is ruined!”) or they can fail in the open position. (Yikes, my kiln won’t heat up at all!)
If they fail, it is not the manufacturer's fault, since they do not make the relays. They test them to make sure they work at the factory, but after that... it is your responsibility. We know that all failures stink and that is why we recommend changing your relays every 12-24 months. If you are a heavy kiln user, you should be smart and change your relays once a year.
Think about it like an oil change or new tires... you wouldn't let your car drive on bald tires or your engine run on old oil. Pick a month and make it kiln maintenance month. Install new relays, paint the bottom with kiln wash, etc. and give your kiln a thorough inspection. Don't be the cautionary tale!!
Finally, if this is something you don't want to hassle with... you can eliminate the problem by upgrading to mercury or solid state relays and almost never have to change a relay again. In our opinion, it's the best upgrade money can buy.
With mercury relays it is important to make sure that regulations in your area don't prohibit them. The following states have prohibited the import of Mercury Displacement Relays within their jurisdictions: CA, CT, RI, IL, NH, MA, MN, ME, VT, NY, LA, MD, WI. If mercury relays are not for you, many kilns come with the option to add solid state relays for an additional charge. Hot Shot takes it one step further and makes all kilns with solid state relays by default.
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