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Max Goldman
What kind of hot water heater should I get?
Max Goldman

I have an old fuel oil hot water heater and would like to replace it soon. Any advice on what to replace it with? I have a fuel oil boiler as my main source of heat. My debate thus far is between: 1. electricity 2. propane (get a tank and eventually convert the boiler to propane as well) or 3. possibly an indirect system. Natural gas is not an option. I have two young children, who will soon be teenagers, so I’m planning for a high demand. Any thoughts/info/advice would be much appreciated.

Re: What kind of hot water heater should I get?

I think you answered your own question. High volume and fuel efficient are your main concerns. I haven't used propane in about 20 years so I don't know how the prices compare to the oil you are burning but I think that the combustion of propane is cleaner which will lower your environmental footprint.

Get the most fuel efficient you can afford. I've said this a lot, I contemplated having a tankless system installed last year until we had a major ice storm knocked out power. I have a gas fuel unit now and it was so nice to have warm showers every morning after feeling gritty from manning the fireplace all night and day.

Re: What kind of hot water heater should I get?


Anytime fuel oil does another spike up in price there is a panic to change to some other fuel source.

For those who have the option to switch to NG & the cost is advantageous, then I say go.

But remember, NG and propane burn more than would a gallon of fuel oil to provide the same amount of heat.

So before doing a switch you have to do a fuel cost comparison between the cost of oil & the cost of other fuels.

The FUEL COST COMPARISON charts below compare apples with apples---they compare 100,000 btu of oil heat with 100,000 btu of propane heat, and 100,000 btu of elec. heat, etc.

Many people switch to propane without checking the price---only to find out they are then paying more than before.

Electric heat is usually MUCH more costly than the other types--in some cases propane is more expensive than heating oil.

You'll have to call your local propane co. to find out what they charge a gallon.

Also call your local elec co. to find out how much a kwh of electricity costs in your area.

Your past posts indicate you're having trouble with an outside tank & NG is not available---I would try to get a Roth tank inside (2 or 3 of them, if you can fit them) if you find the FCC is advantageous in staying with oil.

The fiberglass tanks (the same type the gas stations use are ideal for a buried tank--there is much less likelihood they will leak)---but they take a special local permit & there is the labor cost for installation.

There are also "dura vinyl" "tank mate" custom oil tank covers (site below) in attractive white vinyl that not only dress up the yard, but protect condensate in the oil tank from freezing when an outside tank has to be used---end of "eyesore"---cost is ~$350 plus installation---it's not that big a deal to make one yourself out of framed plywood & cover with vinyl siding--just make sure the "roof" opens up for refills.

For hot tap/shower water, if you stay wih oil, it is STRONGLY RECOMMENDED that you get a 40 gal. INDIRECT HOT WATER HEATER---these look like a standard HWH, but they have no flue or heating source---the water is heated by the hot boiler water via copper tubing & a pump---they last for years without wearing out--the heavy insulation saves fuel costs.

You'll never run out of hot water---even with teenage girls---recommended brands are Triangle Tube Phase 3, Crown Megastor, Weil-Mclain, HTP Superstor & Buderus.


Max Goldman
Re: What kind of hot water heater should I get?
Max Goldman

Awesome info. Thanks for your time, I really appreciate it.

A couple of questions:
1. Do you know, if I have an outside tank with a tank cover, can I use #2 fuel oil?
2. Here are my local costs for fuel. Propane $2.40/g, Fuel Oil $3.05/g, and electricity is $.09/kwh ($.054/kwh off peak). Plugging these numbers in, indicates that Fuel Oil beats propane, but electricity beats both. Am I off base?
3. Why is an indirect water heater highly recommended? Is it much more efficient? I'm having a difficult time calculating any cost savings/justifying the extra cost (vs electric).

Thanks again!

Re: What kind of hot water heater should I get?


Good work on your fuel cost comparison calcs---I think if you do a little more research you'll be able to get a firm handle on local conditions & make a wise choice for your heating equipment.

You live in an area that has some of the coldest temps in the U.S.

Are you closer to Superior or Milwaukee/Madison??

All parts of Wisc. have sub-zero temps for a lot of the winter heating season---the estimate is generally 80 million btu's heating need/winter season.

I was impressed with the low cost of .09/kwh & .054/kwh off peak for elec---here in New England we pay .14/kwh.

It's most important that you get a "feel" for what other homeowners, home builders, real estate agents & heating contractors are doing in your part of Wisc.

I note that natural gas is not available in your particular area, but what do MOST of the locals have for heating equipment??

Only the locals can tell you what works & what's best for your area--the people mentioned above make these decisions every day---house builders & heating contractors have to decide what type of heat to install, real estate agents have to know what heating plant is most efficient---talk to them.

On paper, after calculating your FCC it seems that elec. is the most cost-effective, but elec. heat in a place like Wisc. may not be the best choice---elec. boilers need 23-27 kilowatts to run & produce the 80k btu/hr needed for such heat--that's a lot of juice.

Elec. baseboard is often used in moderate climates, but usually doesn't do too well in northern states--ditto for elec heat pumps---fine for southern states, but not so for northern areas---the colder it gets outside, the less ability the heat pump has to extract any heat from the air when the temps fall below 35 degrees.

Fuel oil has a lot of "punch"---140,000 btu in a single gallon & it can quickly get the water up to 180-200 degrees to get all the heat the home needs--this can't be said for most other fuels.

A ground-source (geothermal) hydronic heat pump would be ideal, but the installation price tag could be $30k.

Some corporations like Steffes offer electric thermal storage "off peak" heat, but the initial equip. cost would have to be looked at.

Do you have any room to get the steel oil tank or a Roth tank inside??

Do you have a crawl space or partial cellar???

The oil tank cover would LOOK nice, but I'm not sure it would prevent the fuel from jelling on Wisconsin winter nites---some of the local oil dealers might have a better grasp of this.

My experience here in New England is that outside tanks are not a good idea---unless there are absolutely no other options.

The steel tank is going to rust due to weather exposure, the sun beating down on the tank on warm days will create internal water condensation that mixes with the fuel at the bottom of the tank---a mild sulfuric acid broth accumulates at the tank bottom & hastens rusting out of the tank.

Even the smallest crawl space under your house should be able to house a tank (especially a Roth tank) & you'll be much better off.

The indirect water heater mentioned is most efficient because it uses no extra fuel to run--for your hot water now you perhaps either have a "domestic coil" inside the boiler, or a separate elec., gas-fired or fuel-fired HWH, all of these are less efficient than an IHWH.

Don't overlook insulation---you heating bill really reflects how much heat is oozing out of your house on a cold day.

If you have little or no insulation in the exterior walls or attic, & the windows are old & drafty, then lots of heat is escaping & your fuel bills are much higher than they would be.

How many gallons of oil would you say you burn in a heating season???

Exterior walls & underside of crawl space should have R19 insulation & attic R40---this is always the 1st thing recommended--- that an insulation co. blow in as much cellulose insulation as you need.

This can be done usually in 1 day & costs several hundred dollars or up to $1500---but still a great bargain.

Heat Loss Calculation:

You should do a free heat loss calculation (below) of your home to determine how much heat is oozing out of your house on a cold day---this will
also tell you if your boiler is properly sized for the house, and you will know the size to order if you order a new one.

HLC's take into consideration the amount of insulation in the walls & attic, the amount of window glass (a lot of heat goes out all types of windows), your location, the type of foundation, etc.

The Slant/fin HLC is more comprehensive---it would be worth a call to the slant/fin technical staff (look for an 800 number on their site) to get their opinion on your fuel choices & heating plant---Slant/fin manufactures oil-fired, gas-fired & elec-fired boilers so is not prejudiced toward any one type of boiler.

Heating Degree Days: a lot of oil dealers and homeowners use the data available at the the local weather bureau to calculate how much fuel they have burned over a heating season & to calculate the efficiency of the boiler--a site for this is below.

If the tank must remain outside, there are additives that may save you from burning the more expensive kerosene: "Hot 4 in 1" @ $8/16 oz. is widely used--also Mitco fuel treatment (anti-gel).

A feed-line out of the top of the oil tank will prevent ice from forming in a bottom feed & supply pipe in sub-zero weather (common occurance).


Max Goldman
Re: What kind of hot water heater should I get?
Max Goldman

Great info and thanks again for your time.

I live closer to Superior. Almost everyone in my area uses propane. Fuel oil is fairly rare. No new homes use fuel oil, the only people who have fuel oil in my area seems to be those that own older homes (mine was built in 1973). So it has been hard to find answers to my questions. I do like fuel oil a lot, no dangers of having a gas and as you say more btu for your dollar. The disadvantage for me is the storage and that it’s not used much around here.

I don’t think I would go to electricity as my primary source of heat. I have actually been trying to get in touch with local contractors, to get more info about a Steffes unit, as a secondary source. I didn’t know electricity was so expensive in other areas ($.14/kwh). I thought my rate was expensive when I compared it to a friend in MN ($.03/kwh, off peak).

I don’t have a really good place to put a fuel oil tank inside, but because of the disadvantages of having one outside, I think I would try to squeeze one in. That’s one of the things that I like about the Roth tank is that it is a lot smaller than a steal tank.

I typically use around 1000 gallons of fuel oil in a year (that’s for heating and hot water, I have an old fuel oil hot water heater).

I have insulated my ceiling to an R40 by blowing in fiberglass.

Also, last fall I had a high efficiency wood-burning fireplace installed, which works great and cuts down on the fuel oil bill a lot. A possible issue I’ve heard about is that fuel oil boilers work better if they run a lot (burns cleaner if it remains warm vs cooling down then heating up again). Since the heat from the fireplace will prevent it from running as much to heat the house, I like the idea of an indirect hot water heater so that it runs a bit more. Any thoughts on this?

Do you think an indirect hot water heater would still be more efficient and cost effective when considering the times of the year when I’m not heating the house and just need hot water?”

My current thought is to stay with fuel oil for my boiler, and store the fuel oil in the house with a Roth tank. Then get a separate electric hot water heater. I think this would be cheaper (with off peak, compared to my current system, and to purchase) and I would be “spreading my risk” among a couple of different (all ready expensive) energy sources. Does that sound like a sound theory?

Thanks again for your time and info.

Re: What kind of hot water heater should I get?


Interesting to hear about the dominance of propane in your area, and glad to hear that you've got R40 insulation in the attic---here in New England (and the rest of the Northeast) is the only place fuel oil is still widely used--also parts of the Midwest, probably because NG pipelines are still being developed.

But even here, a lot of people react to the oil price hike & extra service needed & are switching to NG.

We have a lot more gas line infrastructure in the populated areas & recent innovations in gas-fired condensing boilers that have 96/% efficiency has encouraged a lot of home builders & homeowners to switch.

Still, NG users chafe over having just one utility provider & no control over price increases---oil & propane users can switch & choose among dealers, but the price diff. is usually not that much---it DOES pay to buy everything in July, if you have the storage capacity (35-40% less off season)---check the classified if you're interested in this option, various oil dealers list low price quotes for bulk delivery of 500 gal or more.

I've been involved with oil-fired boilers for over 30 years--still like it despite the price spikes---and now oil-fired condensing boilers with the same 96% efficiency have appeared in strength.

In my home back then, I had an outside tank & not even a crawl space---I excavated 300 sq.ft. to make a partial cellar ($10,000), put in 4 steel tanks & now buy 800-1000 gallons every July for 2000 sq.ft. plus garage workshop.

The big drop in fuel usage came 10 years ago when the tanks moved inside, the attic & exterior walls were heavily insulated & the 30 yr old boiler was replaced with a new 80k btu/hr oil-fired cast iron pin-type boiler ($3k/85% efficiency) & a 40 gal. indirect HWH was added to the boiler---fuel usage immediately dropped 30% & I never run out of HW---and this is just a "run of the mill" boiler---the new condensing units will drop fuel usage much further.

There are zero problems with the fuel oil--due to warm storage & lack of condensation.

As part of my business & training I do all the annual maintenance & repairs to the heating system myself.

Like new cars, new boilers require little repair/maintenance the 1st 5 years of life---beyond that misalignment can cause soot problems, etc.

With oil, the oil filters have to be changed & the boiler must be cleaned annually---and there are small parts that will eventually begin to fail after the 1st 5 years.

It must be said that there is still lots of support in my neck of the woods for fuel oil---thousands of dealers, scores of parts supply houses, etc.

In Wisc. you may not have that kind of support for oil---the more propane dealers in fuel & equipment, the more competetive they will be with each other & the more likely they will value you as a customer as far as pricing the propane & the heating equip. & the service charges.

Also note that high efficiency propane-fired condensing boilers (wall-hung or floor based) are just as efficient as NG condensing boilers (96%).

Canuk is from Canada and has wide experience (along with other posters) in heating equipment---perhaps he'll chime in with some good observations.

I share your feelings on having a large gas tank in the yard---but we had NG in our house when growing up & never had any problems.

Any supplemental heat you can get from the wood fireplace is a definite plus--it's also a lifesaver for the HW system to prevent a freeze-up if the power fails.

There is no problem with reducing the amount of boiler burn time, as long as it doesn't remain idle for weeks on end---it is not recommended to shut down the boiler over the summer, for example---this will cause condensation & combustion chamber corrosion.

I don't feel it is a good idea to put in an elec. HWH---I think you will do much better with a 40 gal. indirect--of the brands mentioned in a previous post.

Many people wrongly assume the boiler will "burn a lot of fuel" during the summer if it has to maintain temp for an IHWH hot---in fact, very little fuel is burned thru the summer months---remember, a boiler burns ~one gallon of oil per hour--the HWH needs only a fraction of that burn time & the heavy insulation inside the IHWH keeps the water hot for many hours.

The boiler is more efficient if it is set up for long heat cycles, as opposed to short-cycling (turning on & off every 5-10 minutes).

Short-cycling indicates the aquastat is usually set improperly.

Try to avoid having the fireplace COMPETE with the boiler---if the fireplace is ON try turning down the t-stat until the wood heat dies down.

If you have only a crawlspace under the house a very small excavation & some concrete work would work wonders to allow you to get a Roth tank in there.

Many of the new boilers are wall-hung--this would free up a lot of floor space that also might make a fuel tank more viable.

Max Goldman
Re: What kind of hot water heater should I get?
Max Goldman

Once again thank you for the info, time, insights and helping me work through my situation, I really appreciate it. My next step is to definitely look into an indirect hot water heater more. Thanks!

Max Goldman
Re: What kind of hot water heater should I get?
Max Goldman

I had my mind made up to get an indirect hot water heater but now I’m getting cold feet. Here is my reasoning:
• Fuel Cost Comparison. Per the hearth.com fuel cost calculations: fuel oil at $4/g would be $36.63 per million btu and electricity at $.057/kwh would be $16.70 per million btu.
• Cost of annual operation (http://www.eere.energy.gov/consumer/your_home/water_heating/index.cfm/mytopic=13010). I calculated fuel oil to be $504/year and electricity to be $250/year.
• Cost of installation. Indirect will be about $1500, electricity about $500.

Am I way off base or am I missing something? One thought I have is if I go with electricity at least my initial investment is low, compared to an indirect heater. If fuel oil prices go down or electric prices go up, at least I wouldn’t be out as much money if I decided to switch to an indirect heater later, compared to starting with an indirect heater and switching to electricity later.

Thanks again for your help and patience.

Re: What kind of hot water heater should I get?


You have to calculate how much it will cost to run an elec. hwh to produce the hw you need, as compared to the amount it costs to produce domestic hw with a boiler/indirect.

An elec. HWH typically requires 4500 to 5000 watts to make hot water, even at the rate of .057 kwh in your area--that's a lot of watts--that's as much as a central AC system or an electric clothes dryer.

You will have to call friends & relatives in your area to find out what they're monthly elec bill is, as opposed to friends who are using propane or oil for their dhw.

Also remember that the hw boiler has in most cases already made the hw for the heating system---the indirect is simply another "zone" that is usually satisfied without the oil burner even having to fire---this is a tremendous savings for most of the year--the circulator pump simply circulates the boiler hw thru the indirect without burning any oil.

One would think that you would burn a lot of oil in the summer---just to keep the indirect full of hot water.

But it doesn't---30-50 gallons will carry you thru the summer.

I've had an oil-fired boiler & indirect in my home for years--I would never change it.

Also be aware that elec hw heaters have a very poor recovery rate---they are slow to provide additional hw once the initial supply is used up.


Re: What kind of hot water heater should I get?

I vote for an underground propane storage tank with a tankless water. Check www.tanklesswaters.com for info. Process of elimanation. Good luck.


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