Electric Water Heater

[ROANIN]

How are newer electric water heaters more efficient than old ones if they are in a heated living space.

[clare]

If in a heated living space they are only more efficient in the summer (when it is a cooled living space)

[Sjouke Burry]

By isolation to keep the heat in, and by decreasing the amount of mass inside the isolation area. Also stopping in time when the temperature is where you want it. And then beep for attention.

[ROANIN]

So if I have an electric heater that is an old Westinghouse that I figure was made in 1954 or so, would I save money with a new model? I figure that any heat lost out of the water heater would be offset the heat required by my furnace.

[Sjouke Burry]

In my country electricity is 2-3 times as expensive as natural gas, So (almost) all people have natural gas heating. Loosing heat from electricity is not compensated on de heating of our house. If you heat with electrcity, then yes, there is no net loss.

[mike]

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by decreasing the amount of

Do you have some math that supports that assertion?

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[Eric in North TX]

That is a decidedly Yankee point of view, you need to consider that to a lot of the country, mid summer is the "unseasonable weather". I spend at least 3 times as much cooling as I do for heating, it is like January, February and summer.

[Ed Pawlowski]

Pretty much. The energy used by the heating elements is the same to heat a gallon of water (say, from 50 to 130) on the old unit as the new. If you want to offset the heat loss in non-heating months, add a wrap of insulation and it will be as good as the new units.

Reasons to change are: old heater has a buildup of minerals in the bottom, dip tube is corroded and not functioning properly, unit is about to spring a leak after so many years.

[ransley]

You probably pay 50-100% more per Btu for electricity, so any heat you get just cost alot more than your gas furnace can provide, they do sell electric furnaces but I bet nobody has them anywhere near you. Because they cost to much to run. Is yours foam insulation, how thick. Look at E.F. - Energy Factor ratings for electric water heaters,

they dont loose alot of heat and are efficient. You can get a new heat pump electric water heater but it costs alot and may not have a payback. Getting a few insulating blankets would be the cheapest way to upgrade but is it near the end of its life. Putting on thermal unions on a new install will save alot.

[Jon Danniken]

They don't make 'em like they used to, mate. Still, I hope you have a full drip pan and line out underneath that thing.

Jon

[Jules Richardson]

Correct - but to be a little more accurate, if you heat with electricity fed using the same supply as the (electric) water heater there is no net loss during the heating season. We have about 14kW of electric baseboard under load control at something like 4.5c/kWH, with the water heater on the regular supply at about 8.5c/kWH, so despite the electric heating there is a benefit to making the water heater as efficient as possible.

[ROANIN]

Actually it is in the basement pretty close to the sump pump hole so if it springs a leak it would not be a big deal except for the incovienience. I am going to probably replace it here soon. Actually you are right, they don't make them like they used to. This thing is a real tank. Very heavy duty looking, however, it does not have a dip tube at all, the pressure relief valve is on the hot line just outside the tank, and the cold water enters the tank at the bottom. I just hate to replace it when it is working fine. Oh by the way, I do have a timer on it. As for the insulation, it is fiberglass. I do not have NG so I heat with Fuel Oil. However I used to have a house that was all electric. This is pretty popular in this area. My electric is about 8.5 cents per KWH and that house cost me less electric than this place and it is a smaller house. So we will see if the bill decreases with the new heater.

R

[Ricky]

You should pour a little water on the floor, or enough to find out which way the water will go when the WH leaks. It might go the other way.

I agree.

[noone]

So you are getting a new water heater?

You could put a pan underneath it and not put in the pipe going to the pump unil later, when you're convinced you need it.

My sump has a plastic lip around it, that mates with the big plastic lid. Water would reach the sump but not go in. I drilled 3 or 4 holes in the lip, but they didn't have much effect, I think. I didn't want to cut off whole sections of lip. I only had one time when there was enough water on the floor to test. But water went in many directions anyhow, and not just towards the sump.

[Red Green]

harry wrote in news: [e-mail]:

That never stopped anybody in this group.

[LSMFT]

Storing hot water is a waste of energy. Get a demand water heater. They make nice oil fired ones. Unlimited hot water, no storage energy waste.

[clare]

Thner is a small benefit - If you can increase from say 75% to 90%, you cut the amount of gas the water heater uses by 15%, saving 15% on the power used by the water heater to maintain water temperature - of which half is reducing your heat supply power, for a net saving of roughly 7% of the power your water heater uses to maintain temperature

- which is alrady a small fraction of the power your water heater uses. If it was possible to save 2 or 3% of your water heater overall power consumption I'd be VERY surprized.

[Steve Newman]

Actually, heat loss is also a function of the difference in temperature, so even though you have less surface area, the hotter water, and thus the hotter tank shell will loose heat faster, so I doubt there is much difference.

[Ed Pawlowski]

"Jules Richardson" wrote

Here in New England, electricity is about 17¢ on average.

[ROANIN]

OK I give up, I tried to google thermal union and did not find anything related to water heaters. What are they?

R