For non oil burners - how to get hot water

I see a lot of posts about no oil delivery for years. If you have oil, I would assume some of you used to use your oil fired boiler for hot water. So my question is, if you are not using your boiler, how are you getting your hot water.

I have a jotul insert and have been using it for just about 1 complete season. I ran out of dry wood last march and had to run the boiler and shut down the insert. From last December to now, I have burned 580 gallons total. I did some testing and I burn about .9 gallons a day in the summer for domestic hot water. If I assume the same year round, that equals 330 gallons which means that I used 250 for heat. I think I'm doing better this year for these reasons.

1 warmer outside.
2. I thought my wood was dry last year, but it is much drier this year so hotter fires.
3. I delayed my programmable thermostat to come on later in the morning which allows me to get the fire going.

I would really like to get the 330 gallons for hot water down, but don't have a clue how to do it. I don't have natural gas (well not the kind you can hook up to a hot water tank), I don't have propane, and don't want to use electricity since it will be extremely expensive.

I have thought about solar, but have not looked into it that much.

The good news for me is that I was burning about 1100 gallons before I made some upgrades and had the insert put in.

Any suggestions would be great.

Sorry if this is the wrong forum.

What would an electric one cost to run? I haven't researched it but if it was 50.00 a month it probably would be cheaper than oil.

Gary

I plan on swapping out my hot water heater with a "On Demand" one.
I have NG but believe they make diesel ones also.
They only heat hot water as you use it, not heat & store & keep it hot until used.
Quite a bit of energy savings with them.
Try "tankless hot water heaters" as a search, may need to refine to "oil fired".

Someone may move this thread to the Green Room, or DIY. But I've been wrong before.

heh, you're probably not going to like this response, especially if there are women in the house...i turn the oil burner on twice a week to shower and do dishes. otherwise it's cold washcloths and dishes piling up. i've been doing this in my current rental and a previous one for almost four years. no choice really, when i can't invest in an alternative that i can move with me easily. i at least have a woodstove currently that keeps the house around 60 when i'm not home to feed it. but i can't justify keeping that boiler going when there's no reason to have all that hot water ready all the time. one gets used to it.

the on-demand heaters, common in europe but rare in the u.s. are a good bet, and there are good alternatives that come with tax breaks available. also better hot water heaters: Stiebel is one brand. something's gotta give. prepare to invest.

You're in the right place....

(1) Electric tank: cheapest to install, maybe $400-$700/yr to operate. Cost per unit of hot water is comparable to that of oil, but much lower standby loss and maintenance costs, so you will still come out ahead.

(2) HP water heater: search for 'geospring' and read threads. $1000-2000 more expensive up front than (1), and requires a large semi-conditioned space to operate in (i.e. an unfinished basement), but costs 50-60% less to operate per year, so has a lower ultimate cost than (1). Makes more sense if you have high usage, AO Smith makes an 80 gallon version, geospring is 50 gallons.

Issues are: do you have enough elec in your breaker box? Can you shut down your boiler for 6 mo/yr without concerns re leaking, rusting out, etc? Many conventional boilers will leak/fail prematurely if left cold for long periods.

A few words I have repeated several times on electric hot water heaters. Conserve use, low flow everywhere, navy showers, no need to fill the tub full. Then, insulate: 6+" of fiberglass sides, top and bottom too, by building a frame under the hw htr. Insulate: all hw pipes, everywhere you can get to. Heat traps: large 12-18" heat traps on both the cold supply and hw pipes to prevent thermo-siphoning. Conservation aside (our water usage didn't change from before to after insulation), the insulation and heat traps cut our electric usage by 50% (electric on a separate meter in our house). Pay-off from less than a $100 one-time investment is huge.

Due to our off-peak electric for hw (electric only 11 pm to 7 am) and a rate of $0.04/kwh, monthly electric bill is less than $5. Yours may be more based on your rate and usage, but with some minimal effort electric by far can be the least expensive way to hot water.

A small oil fired water heater may be cheaper than a boiler and indirect if you're not using the boiler for heating.

Ehouse

Your biggest problem is that you think electric is too expensive. Using your numbers you are spending 100$ a month for oil hot water. Enter the electric tank water heater. You will not spend 100$ to heat water unless you have an exceptional consumption figure or your power cost is exceptional.

Seriously, my whole power bill averages 100$ year round and I heat water, a huge hot tub, range, fridge, extra freezer, lights, etc. Power here is cheap at 10 cents per KwH

I don't believe that using a boiler system to heat water is ever going to be cost effective unless you already have the boiler running for home heat.

Electric water heaters are very efficient especially when turned to no more than 120 Degrees. WHere you dont need to mix cold with it for a shower.
WHen i do this i dont even notice a bump in my electric bill. OIL for Hot water NEVER.

Thanks everyone for the pointers. I just assumed that the electric water heater would be too much to run. I changed my boiler to a cold start boiler so shutting it down in the summer should be possible. The oil fired boiler I put in uses a superstor for hot water. My previous boiler had on demand but my water is very bad. I have 4 filters trying to clean up the water but there it still cakes up the on demand so the heat didnt efficiently heat the water. I was told that the inside of the on demand system kept getting caked up and didnt let the heat through to heat up the water.

The new boiler saves me about 350 gallons per year and the insert seems to be saving me about 230 gallons.

Turning on the boiler twice a week won't cut it at my house. Nice thought though.

There is a possibility that I ca get a superstor for free and I was thinking of using it as a heat exchanger for solar. I would have the heated water from the solar superstor feed the superstor connected to the boiler.

I currently have a mixing valve on the superstor. I was told that the temp in the superstor needed to be x degrees to kill any bacteria (or something like that). Then use the mixing valve so no one gets scalded. Anyone know if that is true? With 4 adults taking showers, and not navy showers, I have never run out of water. Lowering the temp on the superstor coould be a good zero cost start if the water will still be bacteria free. I think my mixing valve sets the water temp around 110.

Any idea how I can determine what a water heater would cost me to run? I'm in NH and I thought the cost of electrify was high here. I just checked and it looks like psnh charges 17 cents per kilowatt.

I'll do more research.

Thanks for everyone's help.

Psnh reports that a 20 gallon water heater costs $77 per month. Ouch!

On a BTU vs BTU basis, $0.175/kWh is the same as $6/gallon oil (assuming elec is 100% efficient, oil is 80%). So, at that rate, elec water heating is almost 2x as expensive. Of course, if you are burning a gallon on standby for every one you burn for DHW, its a wash.

A HP water heater would be cheaper to operate.

On city water they already have chlorine in it to kill the bacteria ,i suppose on a well you might need to worry about bacteria.

Ouch, indeed. We have a 51 and 40 gallon electric hot water heaters, insulated as indicated above, wife and I in the household plus guests, $5 month operating cost.

i have a 60 gallon electric hot water heater. My wife/I/6 month old daughter in the house.

The hot water heater is on a off-peak meter, it only runs about 12 hours a day. It costs about $0.09/kwh. for a monthly bill of about $20. We arent crazy about taking short showers either, just normal use.

Inlet water temperature varies dramatically, from about low 60's to mid to low 40's. January, the bill is usually around $30, in june/july it is about $14.

I like the heat pump hot water add-on units. However, for now, the return on investment isnt quick enough to justify the unit. Its always good to make sure that you drain from time to time to get rid of material that has settled out/corrosion by products.

I was using about a tank of oil a year just for hot water and decided that I was tired of spending around $1000 a year on oil for it so last year I installed a electric hot water heater and my electric bill went up around $16 a mth at a rate of about $.13 a kwh that's for 2 adults and one 3 year old.

Go electric. Insulate the heck out of it and the pipes. Virtually maintenance free and highly reliable. I have a 60 gallon that has NO problem with keeping up with me/her/23yr old girl and two little ones, washing machine and dish washer. I have never run out of hot water.

Sounds like my results as well but we have 5 people in the house. I have the temp set at about 120
The big drawback with oil is not only the price but your chimney starts drawing out the heat the minute your burner shuts down if you are using an oil boiler with a heat coil. Furnace has to cycle on many times a day just to maintain hot water even with no use at all.

I've just ripped out my oil furnace with hot water coil for the same reasons you cite. Too expensive.
Might have been doing almost a gallon a day for hot water, too.
No way you'll save money going electric.

I put in a Buderus oil burner and a storage tank http://www.buderus.us/products/storagetanks/tankssolarsystems/logaluxsm300sm400.html with oil burner coil on the top and solar panel coil on the bottom.


If you cut back the temp on the mixing valve you'll be sucking a tiny bit less hot water out of the tank.


Guy down the street (with solar panels)had the same system but originally had a separate tank for the solar and it used more oil than a single tank. He now has a single tank with two coils.

My roof points south so I have a perfect roof and it is not shaded much but it is all oak trees so I'll probably make more hot water in Winter than Summer.


I have a chimney to remove and some roof repairs before the solar panels can go up.


My goal is to shut off the furnace when I no longer need heat in the Spring and not have to hear it run again until Fall.





I also went direct vent on the oil burner to get rid of the chimney - it sucks in air from outside the house and doesn't have the loud obnoxious fan a power vent has.

How big is the HW tank? It is me, wife, and two younger daughters. Also, for those with electric HW, how quick is the recovery. Mostly doesnt really matter because we all take showers at different times of the day, but curious when we have guests.

The superstor I have is 60 gal, I would think that the 20 gal would be small for a 4 bed room house.

I propose that it won't cost any more to have a 60 gallon electric water heater than a 20 gallon electric water heater. They have the same electric demand, you are heating the same amount of water, what you get with the larger tank is more hot water consumption before running out.

Your power is relatively cheap. Those who have made the switch report a minimal price increase to their electric bill.

Using electric as a fuel has other benefits such as a pretty consistent price, a steady supply with no risk of some yahoo iranian causing an increase, no CO danger, no fire in the house, no noise, no chimney to leak water or heated room air. There's more but the most important thing is that it will be cheaper.

I agree with highbeam....you should go electric, and get a 60-80 gallon, well insulated tank (usual 'rule' is 20 gallons per bdrm). Your boiler is aok being shut down for the summer. The standby losses on a modern electric tank are very low.

If you want more numerical proof, you have to estimate your standby losses in the summer.

I put a run timer on my boiler to track my usage accurately. My boiler has no calls for heat cuz I switched my heating to a HP....

My wife and I and two young kids use ~100 gallons of oil in a tankless coil, per year to actually heat water that was delivered. But my boiler still burns ~300-350 gallons a year. AND I up-insulated the case AND eliminated a thermosiphon in the hydronic loop. So, minimum I am burning 2+ gallons of oil on standby for every 1 I burn to heat water. If your standby losses are similar, you are spending >$1000/yr on DHW.

To estimate YOUR oil standby, take your summer usage, and subtract off maybe 0.2-0.3 gal/day for actual DHW delivered.

This is pretty interesting. A couple of points I'll comment on with more questions.

PSNH - power company for NH reports $77 per month for dhw from an electric tank. Maybe they are overpricing it, but if anything, I would think that they would underestimate it. At $77 per month, I'm talking $924 per year which would be the same as burning .87 gal per day at $2.91 per gal. A little low for oil, but my prebuy price is 2.99 this year.

Can you explain how you came up with the 100 gal for dhw, but 350 total. I get the total, but don't understand the other. I have been tracking my usage for 10+ years with my old and new boiler. The least average usage I saw in the summer was .87 gal per day. When I looked at the system 2000 website they indicated the oil usage in the summer should use .2 gal per day for dhw so the .2 you have above sounds interesting. My heat is definitely turned off in the summer. The only thing I couldn't tell from the system 2000 web site is if the .2 was for their solar/oil unit or just the oil unit.

Can you show me the timer you have on your boiler. I could use that in the summer when the heat is off so I could get an accurate reading for dhw oil usage.

I'm leaning towards solar since it will be almost free once it is installed. Just cost a little for the electricity to make the pumps run.

Thanks again

If you're still using your boiler for heat in the Winter then an indirect is going to be your most efficient option when you factor Summer/Winter into the equation. If its just for hot water and the boiler is for emergency/backup heat I'd definately go with an electric. I looked into the heat pumps but decided I don't have the opportune setup (small room) and because I'm so far North with a heated basement I'd only be gaining efficiency 4-5 months/year.

I'd avoid the oil-fired hot water heater. Another burner to service + the open flue wicks heat out of the tank just like your boiler does. Keep the btus in a tank that doesn't have a natural chimney and the water will stay hot for days. I've got a mixing valve on my tank so a 40g behaves more like a 50 gallon. I'm looking for a cheap/free indirect so I can preheat my hot water with both a homemade solar option and also do a post-purge on the boiler.

They work but most boilers have a much smaller r-value than a tank's typical r19+, plus larger piping will migrate heat away faster than smaller regardless of heat traps etc. I'm talking pennies difference per cycle and everyone has to cost it out for themselves. My goal is gallons of heating oil, and quite honestly dollars/shower often takes a back seat to gallons per year. I'm not crazy with it but a 10yr payback period for me is not out of the question. In the back of my mind I'm always thinking: "Hmmm. Straigth of Hormuz+terrorist attack= $10/gallon heating oil! That changes figures in a hurry.


I like the idea of automatic dampers but personally have had a lot of problems with my own as well as others I've seen installed. They're kinda cheap and take a beating being so close to the hot flue gases. Plus a boiler/tank that only fires 2-5 minutes to retain temperature is going to soot up a lot quicker than one that has to charge an indirect. Either one is pretty wasteful compared to solar, on-demand or good ol' fashioned conservation. I saved more by putting an egg timer in the bathroom for my daughter than I did by installing a 5k high eff heating system. I suppose if I get rid of the egg my payback period would improve, but that doesn't make much sense either. I'm not crazy.

No, I'm not. I'm not crazy.

Not crazy