Water Heaters - Water heater replacement dillema driving me crazy

This has been on going for about the last two months...

Let me start by saying I am an electrician...

Ok, I want to take my gas chimney vented water heater out of the chimney to put a second wood stove in my basement. To do this, I found I have to construct a type B gas chimney up through my roof to vent the water heater. I havn't use my furnace in about 5 years, I heat with wood. Even tho I should have it, I don't need the furnace connected.

I got a whole list of all the type B pipes, elbows, etc i need, and I know where to put it...Through a closet, through a hall. I restored my 1890's house years ago so I would have to box this in behind a shelving unit or something, make it look nice...etc, etc, etc...alot of work that i don't want to get into unless I need to.

The only reason I want to keep my current syle unit is because its cheap to operate (about 28 bucks a month) and its cheap to replace chimney vented units, I think.

I was under the impression an electric water heater would cost a fortune to operate, a power vented water heater would cost a fortune to buy.

...then I read an article on average a gas water heater is around $30 a month and electric is around $40 a month. I don't mind the sound of that at all. Then I read about the tankless water heaters. They are slightly cheaper to operate. All these water heaters seemed to cost around $400. If I bought a water heater, I would prefer to pay between 300 and 500

I would much rather buy one of these then install the type b gas chimney. But which one do I buy. I am an electrician and have no idea. I would love some insight from the people who know this stuff :) Which one would be best for me.

I currently have a 30 gal I think. If I go with a tank, I might go with a 40 gal possibly.

I could do the soldering myself ( I installed my current water heater) and electrical would be no problem at all.

Thank you so so much.

I can pretty much guarantee that you won't find a usable and reliable tankless water heater for $400. A decent gas-fired tankless will be at least $800 to $1,000 and then you might have to add another two to six hundred dollars for installation. Gas tankless water heaters often require new piping from the gas meter to the unit and this piping is usually not a DIY job. They also often require stainless steel exhaust piping and this gets pricey pretty quickly.

In my opinion electric tankless is just something to be avoided although some people seem to like it. Generally speaking I just plain dislike tankless heaters no matter what the source of heat.

As an electrician you already know about load calculations and demand factor. Your service may not be able to support electric tankless because any unit that is going to supply more than just warm water for washing your hands is going to take a peak of about 120 Amperes at 240 volts, or close to 30 kilowatts. That pretty much means a minimum of a 200 Ampere service and LOTS of copper between the panel and the heater. A tank-type electric will typically have a load of 4.5 to 6 kw, usually the lower. If you do go to a tank type electric water heater you will want to definitely get a larger tank than your present gas-fired unit. Electric tank-type water heaters are slow in recovery, a typical gas water heater will recover three to four times faster than an electric model of the same size.

Electric tank-type water heaters have lower standby losses than do gas-fired water heaters. I like long hot showers and during an extended power outage I was still able to shower on the third day from an eighty gallon tank. I would have never been able to do that with a gas-fired heater, even an eighty gallon unit. Electric water heaters have an overall efficiency of close to 95% whereas a typical natural draft gas fired unit is going to be in the 60% range.

It takes 3,414 BTUs of heat to raise the temperature of one pound of water one degree Fahrenheit. There are roughly 7.5 pounds of water in a gallon so with these constants and your cost of energy you can come pretty close in figuring which water heater is more economical to operate. Remember that electric water heaters generally last a bit longer than gas units and they typically cost a bit less than gas units.

Wow thats a big help for me. Thank you. I didn't know the tankless water heaters were 120 amps. I thought only the on demand tankless water heaters were 120a. They might even be the same thing. I don't know. The only water heaters without a tank that I've wired were indeed 120 amps tho. Good thing it was next to the panel! The home owner hates it too, due to lack of pressure.

I have no problem picking up an electric water heater now, it would save me alot of work. Is it safe to say that my gas water heater costs 30 bucks a month and an electric would only be slightly more. 45 a month maybe? I know there are alot of variables involved, but I figured electric would be at least double what the gas costs. Hence why I was going to put in a chimney. I got this assumption from the cost of running electric baseboard heat.

Again thanks for your help. Beer 4U2

Is it safe to say that my gas water heater costs 30 bucks a month and an electric would only be slightly more. 45 a month maybe?
No, that is not a safe statement. It depends entirely on the rates for electricity and gas. Don't forget that you have to look at the total cost and not just the unit price.

For example: My gas bill is divided into customer service charge of W dollars per month, gas usage at X dollars per Therm, delivery charge at Y dollars per Therm, gas conservation program fee at Z dollars per Therm and then local utility tax of 6% on all of the above.

My monthly gas bill during the summer is about $15 and that was with a customer charge of (I think) $5 or $6 dollars a month. The gas utility has petitioned the state regulators to raise the customer charge to (Again, I think) about $15 a month. The customer service charge is assessed whether or not you use any gas and then the gas consumption is added (along with any other fees) to that. So if my average monthly gas consumption last summer was about $10 plus the $5 service charge (total of $15) and if the state regulatory board grants the new customer service charge my summer gas bills next summer will average about $25 or a $10 per month increase.

At that point it may theoretically be more economical for me to use electricity to heat my water since my summer electrical rate is about $0.077 per kilowatt. The stickler is that I would STILL need to pay the customer service charge on the gas, even though I wasn't using any gas, because I also use gas for heating my home. I can't just cease gas service for several reasons including the fact that the weather is so changeable here that sometimes even in the middle of summer it can get cold enough to want to turn up the heat.

Keep in mind that as far as across the country averages go I have a rather low to very low electrical cost and a moderate cost to somewhat high gas cost and it still is cheaper for me to use gas for water heating.

As mentioned by others, a tankless would be near a grand, and the install could easily exceed that, due to the very large new electric circuit needed, or the new larger gas line AND all stainless steel vent required for a gas model.