Prepping your home for a long vacation is a great way to save some dough. You can (and should!) unplug vampire devices and shut off and empty your always-on water heater to shave a few bucks off that month's utility bill (Don't turn off the A/C though). But if you come home and turn your hibernating tech on in the wrong order, you risk doing serious damage to your water heater. Here's what you need to know.
Your water heater is designed to keep heating and reheating the water in its tank, whether or not anyone is there to actually take a steamy bath. So if you want to be super attentive about wasting resources, it's a good idea to turn off power and water to your water heater before you leave for a long vacation.
But beware, problems can arise when you return home to turn your household systems back on. This Old House has a great feature about disasters that could happen to your house while you're on vacation, leaving us with this gem about re-connecting your water heater:
Many homeowners who are extra vigilant turn off the water and the power to their water heater before they leave, to avoid any risks of floods or fires. But that can spell disaster if you turn things back on in the wrong order; the tank needs to fill with water before you switch on the heater.
If you turn on power to your water heater before it's filled up with water, there's a good chance you'll burn out the element in your water heater, at best. They're not terribly expensive to replace—only $10 or so—but you'll have to wait to take that post-vacay shower. Some cases could do even more damage, so be mindful of how and when you power up your post-vacation home.
(Images: Flickr member Matt Stratton licensed for use under Creative Commons, Flickr member marlb0r0 man licensed for use under Creative Commons)
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It's not clear to me why you would drain your hot water heater. Merely turning it off (gar or electric) would suffice during vacation.
At our vacation cabin at Lake Tahoe, we open it in the spring, fill up the hot water heater, and leave water in it all season, though we turn it off between visits.
That's what I was wondering. Why drain?
Most of the time, this advice is used only when you are going away for a winter vacation, and the water could potentially freeze and burst pipes or perhaps the water heater itself. But if you are worried about the water leaking out and making a mess while you are away, you might drain. Example - h/w heater is adjacent to kitchen or bathroom where you have vinyl tile.
Considering we have a tankless water heater that only turns on when water is running through it, I'm glad this is something I never have to worry about.