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Smart water heater device

I came across this crowdfunding campaign and am thinking about getting one for my water heater. It turns your tank water heater into an on demand water heater with a smart phone app, which is supposed to save you money. What do you think?


Re: Smart water heater device

I would say that it exaggerates savings.


A. Spruce
Re: Smart water heater device
homeimprover wrote:

It turns your tank water heater into an on demand water heater with a smart phone app

A fool and their money are soon parted . . .

Nice stickers though!

Re: Smart water heater device


Please get one of these, try it and report back in a few months. Then we'll ask you to prove your claims.

For ON DEMAND INSTANT hot water - you just can't use a tank water heater, no matter what gadgets you attach to it.

Re: Smart water heater device

It makes sense to turn the water heater off the hours that you don't use it. Not a ton of savings, but a good amount over time. Good thing that it pays itself off. I didn't realize that water heaters emit 1000 lbs. of Co2! I'll definitely let you know if I get one.

Re: Smart water heater device

If you have an uninsulated or very poorly insulated water heater, this thing will work, but it would not be the best choice for reducing the operating cost, insulation would.

Back in the early 80's, I used the formula's for calculating heat loss that I got from the book "From the Walls In" by Charles Wing for figuring the cost of operating my 40 gallon electric water heater. It was an old model with poor insulation, about an inch of fiberglass. The water heater was in an uninsulated garage in Virginia Beach so in the winter months, the calculations came out to just under $10/month to store the hot water. The rest of the cost was in heating the water for use, about $40/month. In the summer, the cost for storage was less than half, but the usage cost remained the same.

But wrapping the water heater with R-11 wall insulation held together with duct tape, (was not pretty) and insulating the pipes between the heater and the wall they disappeared into, the calculated cost of storage in winter dropped to under $2/month, less than $1/month in the summer. The calculations seemed to bear out in my electric bill, but without meter dedicated to the water heater, it cannot be proved.

BTW, the water heater was set to 140.

Re: Smart water heater device

I wonder if turning off then turning back on a water hear and maybe even the house heat on a daily schedule provides much of a savings. The heater has to work longer to bring the water back up to temperature. In a house besides heating the air all the materials, drywall, furniture and furnishings, will absorb heat to get the temperature back to the set point.
It's always been said setting back on a daily schedule will save energy, like using programmable or the Nest thermostat. Are there any scientific studies that show this is true? And what kind of savings?
I realize this is heracy. So feel free to blast or correct me.

Re: Smart water heater device
homeimprover wrote:

It makes sense to turn the water heater off the hours that you don't use it. Not a ton of savings, but a good amount over time. Good thing that it pays itself off. I didn't realize that water heaters emit 1000 lbs. of Co2! I'll definitely let you know if I get one.

I'd like to respond to this as well: We know that your car spends/wastes more gas in a stop n go traffic situation, because the biggest waste is going from 0 to 30.

The same would apply to water temp. Raising water temp to 110 - 120 F, a few times a day would be very wasteful.

Therefore, shutting the water heater and starting it again, won't save energy, but will waste energy. Disagree? Do it and show me the "savings".

Like I said before, if you want instant on demand hot water, replace the tank WH with a tankless.

Now, whether to get a tankless WH or not, depends on other factors, and we are not discussing them right now.

Re: Smart water heater device

Adequate insulation is definitely the key to energy savings. However, if your water heater is within the conditioned envelope of the home, energy lost through radiation to the surrounding environment is not wasted in the winter when you're heating anyway. However, if you have a naturally aspirated (read: not a super-high-efficiency) water heater, every time it runs there is significant heat loss up the flue. Since your furnace likely is more energy efficient in terms of heating the air than radiation from your water heater, it's a good idea to minimize radiant energy loss from the water heater by beefing up the insulation.

The principle of turning the thermostat down and back up is based on the fact that energy loss is greater when there is a greater temperature differential between that which is being heated and the surrounding environment. If the water heater is allowed to cool down during periods of disuse, the energy loss decreases as it cools. Even with the need to run the water heater for a longer period when demand returns, the overall energy loss during the time of disuse is less than if the water heater's temperature was maintained. If you timed the cycling of the water heater, comparing maintained temperature with setback temperature, you should find that the "on time" is less for the period when a setback temperature is used. The difference will be more noticeable the cooler the water heater is allowed to get.

The device in question may provide a "learning" ability, like the Nest thermostat, that figures out what your usage patterns are. However, the cost of the device is likely to be so great that it may take several years to get a return on investment. A simple timer with a static program is much cheaper (though I don't know if they are available for gas water heaters) and will realize a much quicker return on investment.

Re: Smart water heater device

I would think the advisability of turning the water heater down is somewhat analogous to having a setback thermometer on the house furnace. If you are gone from early morning to evening, it makes sense to have an automatic thermostat set the heat down at bring it back up at the anticipated time. However, such setback thermostats are relatively cheap, so that the payback period is short. I do question the "smart" Nest type thermostats.
Sometimes we can be too smart by ten! Just because something CAN be regulated remotely, does not mean it is necessarily worth it!

Re: Smart water heater device

It's anecdotal hearsay, but a friend of mine hooked a timer to his older electric WH so that it was ready for use only mornings and evenings when they bathed, washed dishes, etc. He claimed a savings of $15 a month taken over 2 years, and he was pretty meticulous about accounting and not wasting electricity. Like a setback thermostat it can make a difference but you also have to live around it's characteristics or you lose those savings.

You can also save something by not having the top element working. Here's why this works- although it takes a set amount of energy to heat the water enough to reach thermostatic cut-off, you can achieve that heating with a smaller heat source spread out over time with less energy than it takes to do the same thing quickly when the second element kicks in- the time factor makes the difference. The downside of course is that you might run out of DHW and it will be a long wait for more. I would also not expect much in the way of savings but the difference is there.



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