Programable thermostat for water heater?
| Posted in Energy, Heating & Insulation on
Love my Honeywell programmable thermostat for my furnace. Is there such a puppy for a water heater?
I figure why heat the tank more than necessary for safe hot water when I don’t use it much more than an hour a day. Yet, that minimum temperature is not hot enough for a decently blistering shower at 5:30 in the morning. Rather than suffer frostbite on my toes from that cold, cold basement slab while turning up the water heater at 5 AM (can’t I sleep, honey?), I’m hoping to find a product that will allow me to set it and forget it.
Replies
Never heard of a programable water heater stat, and wonder if the savings would really be there but... if you were admant you could use a low voltage programable thermostat and a transformer with a relay rated for the load. I am thinking this is would not be a good diy project unless you had some experience.
bake
If it is an electric HW you can use a time clock to just turn if off at nite and during the day if no one is home.
GAS! GAS! GAS! as we've been hearing on TV lately.
I get calls to install timers, "Little Grey Box" is one brand, on electric water heaters. People imagine that they will save real money. Usually I advise against it.
There are two fairly rare conditions that a timer could save you money and in each case the timer is not the best solution.
1) You don't use hot water for extended, over 24 hour, periods. In this case the water is maintained intermittently by the heating element. This energy use is largely wasted. A timer, if set to match the use schedule, could both save energy and provide hot water when you get home. The problem is that most of this can also be done with a $12 switch. Even less if you just flip the breaker off.
Turning the water heater off when you are not going to use hot water for 24hrs will save as much energy. You will have to wait a bit, about 40 minutes typically, after turning on the switch to get hot water but this is usually not a problem. One other point. I have yet to see a timer that was adjusted properly to match usage and correct for power outages.
2) Your water heater has little insulation. This situation cases the heater to cycle rapidly even when no hot water is used. Installing a timer here would, again if set properly, save money and still give you hot water when needed. Here again simply switching off the heater would do as well for saving energy. But the best solution is to either get a replacement hater heater or to install insulation on the existing one.
The cost of a new heater, to replace an old and poorly insulated one, can be made back in a year or so. The pay back on adding insulation to a water heater is even faster. A $10 insulation kit or, even better, bulk insulation if it is on hand can pay for itself in a month or two.
Using the breaker as a switch, most are rated for it, is both a cheap and effective way to save money and makes sense for homes where there is no hot water needed for days or months. like a vacation home. Installing a switch to control the water heater is more expensive but can make sense if having the control in an easy accessible spot reminds you to turn off the heater when you go on vacation.
In most cases, houses where hot water will be needed within 12 hours, insulation is the best answer. If the water hater is old a replacement is likely a good idea as it is nearing the end of its service life. If it is relatively new adding insulation is a cheap and easy weekend project that yields good savings.
If this is a gas heater insulation is less effective but it still can be a good idea that can save money. If you do insulate a gas hot water heater make sure you don't obstruct air flows to the stack or burner and stay away from the fire box.