heating domestic water

heating domestic water

PostBy: bowman On: Fri Mar 07, 2008 12:59 pm

New member thinking of going to coal. Is anyone using their coal boiler to heat domestic water during the summer? If so how well does it work?
Looking at a keystoker.
bowman
 
Stove/Furnace Make: none yet

Re: heating domestic water

PostBy: coaledsweat On: Fri Mar 07, 2008 1:42 pm

Our fearless leader himself and a lot of other members use coal for domestic water all year round. The draft is the key to using it in the summer months.
coaledsweat
 
Stoker Coal Boiler: Axeman Anderson 260M
Coal Size/Type: Pea

Re: heating domestic water

PostBy: LsFarm On: Fri Mar 07, 2008 2:19 pm

Hello bowman, welcome to the forum.. The quick answer is yes it can and is being done...

But the deciding factor is going to be coal supply.. where are you located?? what will your source for coal be??

[fill in your signature so we all can tell]

If you are in coal country, or can get coal in quantity, without having to add a lot of cost to the coal because of transportation costs and distances, then it makes sense to heat your domestic hot water with coal...

The ability to keep a stoker boiler running during the summer will depend on having a good chimney, and have a good 'keep-fire' timer on the boiler...

One important thing to think about.. just how much do you spend on hot water?? If you have a large family, then your domestic hot water can cost you a lot. But if you only say, run a load of laundry every other day, and ony two showers per day, then you will be better off with an on-demand hot water heater.

The big user of heat for hot water is standby losses. To keep 40-50 gallons of water hot for 23 hours so two showers can be had in the morning, is pretty wastefull, regardless if it is electric, oil, gas or coal heated water..

So there are several sides to using a boiler all year long for hot water.

Greg L.

.
LsFarm
 
Stoker Coal Boiler: Axeman Anderson 260
Hand Fed Coal Boiler: Self-built 'Big Bertha' SS Boiler
Baseburners & Antiques: Keystone 11, Art Garland

Visit Lehigh Anthracite

Re: heating domestic water

PostBy: Yanche On: Fri Mar 07, 2008 3:33 pm

LsFarm wrote:One important thing to think about.. just how much do you spend on hot water?? If you have a large family, then your domestic hot water can cost you a lot. But if you only say, run a load of laundry every other day, and ony two showers per day, then you will be better off with an on-demand hot water heater.

The big user of heat for hot water is standby losses. To keep 40-50 gallons of water hot for 23 hours so two showers can be had in the morning, is pretty wastefull, regardless if it is electric, oil, gas or coal heated water..

So there are several sides to using a boiler all year long for hot water.

Greg L.
You can minimize boiler heat losses if you have a well insulated indirect hot water heater. With this system your boiler water heats the domestic water inside a insulated tank. When there is no demand for re-heating domestic water the boiler can idle down to a lower temperature, one that is the result of any "keep coal fire alive" timer. When the hot water heater thermostat calls for re-heating the combustion blower raises the boiler temperature and the re-heating begins. If the coal boiler is located in an air conditioned space don't forget that you are spending dollars to cool the boiler heat you can't turn off.

I'll be heating my domestic hot water with coal this summer. I heated it with an oil boiler last summer and kept good oil usage data. At my costs for coal I expect significant savings over oil. I have an indirect hot water tank and my boiler is not in my home.
Yanche
 
Stoker Coal Boiler: Alternate Heating Systems S-130
Coal Size/Type: Anthracite Pea

Re: heating domestic water

PostBy: stoker-man On: Fri Mar 07, 2008 5:34 pm

From my experience, most efm boiler owners use theirs to heat domestic hot water all summer.
stoker-man
 
Hand Fed Coal Boiler: 1981 efm wcb-24 in use 365 days a year
Coal Size/Type: Anthracite/Chestnut
Other Heating: Hearthstone wood stove

Re: heating domestic water

PostBy: gaw On: Sat Mar 08, 2008 8:22 am

I have the Keystoker KA-6 and it has fire year round. It heats all domestic water using the internal coil type domestic water heater. During the summer I burn about 100 pounds a week. My coal cost is about $.08 per pound, so about $8 a week. I don't know if it will be economical for you or not. Another reason to keep the fire all year is that it will increase the life of your boiler indefinitely. I have seen boilers in continuous use for over fifty years and internally they look the same as if they were only a year old.

Short answer is yes they work great as hot water heaters in the summer, economical? maybe.
gaw
 
Stoker Coal Boiler: Keystoker KA-6
Coal Size/Type: Rice from Schuylkill County

Re: heating domestic water

PostBy: bowman On: Sat Mar 08, 2008 8:46 am

Thanks for the replies.
My next question. I have been on the forum for a couple of days checking out which boilers the members are using. I haven't found anyone using a Keystoker. Correction one.
Is there a reason for this?
What size boiler would I need for a 1800 sf cape, well insulated newly constucted in Maine?
bowman
 
Stove/Furnace Make: none yet

Re: heating domestic water

PostBy: LsFarm On: Sat Mar 08, 2008 10:28 am

For a new construction, well insulated with good quality windows, The small keystoker boiler would be more than adequate. The rest of the boilers start at around 130K which I'm pretty sure would be a lot more BTU's than you need for an 1800 sqft house, unless you plan on adding on, or heating a garage, shop or a basement not included in the sq.ft measurement.

Greg L.
LsFarm
 
Stoker Coal Boiler: Axeman Anderson 260
Hand Fed Coal Boiler: Self-built 'Big Bertha' SS Boiler
Baseburners & Antiques: Keystone 11, Art Garland

Re: heating domestic water

PostBy: watkinsdr On: Sat Mar 08, 2008 10:50 am

Please hook up with fellow forum member: 1975gt750. Just do a site search. He's augmenting his existing oil fired boiler. Based on his posts, he's had outstanding success with his Keystoker KAA-2. He's posted some really good pictures of his installation too.
watkinsdr
 
Stoker Coal Boiler: AHS S260 Boiler

Re: heating domestic water

PostBy: stoker-man On: Sat Mar 08, 2008 10:52 am

I can offer info as to how much it costs to heat domestic hot water for a year.

When we built our house in 1977 we installed an oil boiler and baseboard heat. 1977 was also the time of a previous "energy crisis" and just before the second "crisis". As a result, we also installed a wood stove in the living room. We decided from the beginning that we would only heat with wood and use the boiler for domestic hot water only. Over a period of 30 years our oil usage was a consistent 250 gallons per year, for a family ranging from two, then five, and now two again. That equals about $750 per year at the current price of oil.
stoker-man
 
Hand Fed Coal Boiler: 1981 efm wcb-24 in use 365 days a year
Coal Size/Type: Anthracite/Chestnut
Other Heating: Hearthstone wood stove

Re: heating domestic water

PostBy: europachris On: Sat Mar 29, 2008 8:28 pm

Now that summer is approaching - I have this nagging question regarding heating domestic hot water all year round with coal....

How much heat does the boiler dump into the house during the times when hot water is not being demanded? The coal fire has to keep burning at some minimum level otherwise it will go out. If no heat is being used for hot water, that heat has to go somewhere. Either the overtemp shuts down the boiler and the fire goes out, or that heat is going into the house.

My Keystoker burns I would estimate less than 1/2 pound per hour at idle. But, that is still 6500 BTU input, give or take. That might get you 4000 BTU into the water per hour, or the equivalent of 1100 watts electricity, approx. That heat has to go somewhere, and that is like running an electric space heater in your basement all the time.

Most modern homes are well insulated and have central A/C. While running coal to heat hot water might save $ per BTU, that would be offset, IMHO, by the extra cost to run the A/C to remove the extra heat load from the idling coal fire.

I suppose if you had a family (and a larger one at that) home all day doing laundry, etc. and using hot water, it would work out. We are gone all day, so our hot water demand is mostly a little in the morning and a lot at night and on weekends.

I can see, however, how running the unit 24/7 would likely make it last longer than shutting it down every summer. The inside of my Keystoker looks almost like it did the day I started it last fall - no rust or corrosion from use. But, once shut down, that will allow the corrosion process to start unless it's cleaned, rustproofed and kept very dry.

Chris
europachris
 
Stove/Furnace Make: EFM 350/Iron Fireman
Stove/Furnace Model: Custom bituminous burner

Re: heating domestic water

PostBy: e.alleg On: Sun Mar 30, 2008 12:38 am

While it isn't as efficient as using a direct on-demand water heater, it is still cheaper. Coal is less than 1/2 price of oil, electricity, or propane so even though you waste some heat through standby losses you'll still save some money. Plus as long as the boiler is lit you can get heat out of it, some summer nights get down in the 40's and it's simple to take the chill off as long as the coal is burning just stoke it up for a little bit.
e.alleg
 
Stove/Furnace Make: EFM
Stove/Furnace Model: 520

Re: heating domestic water

PostBy: Richard S. On: Sun Mar 30, 2008 1:54 am

europachris wrote:and that is like running an electric space heater in your basement all the time.


The larger furnaces are insulated on the ouside, they aren't meant to provide radiant heat in the room but they do provide some when running a lot. ;) In the summer when idling the heat being dumped into the room is mostly from the flue pipe and that's minimal. This is probably not something you want to do unless you have large insulated unit.
Richard S.
 
Stoker Coal Boiler: Van Wert VA1200
Coal Size/Type: Buckwheat/Anthracite

Re: heating domestic water

PostBy: Highlander On: Sun Mar 30, 2008 7:19 pm

I burn coal for domestic hot water, and my useage was about 12# per day or about 85# per week in a Harman VF3K. I keep the boiler water at 140 degrees which is plenty for making hot water.

During the warm weather, the boiler definately adds to the warmth in the basement, I come home at night and open the door to the workshop to let the cooler air in through the screen door. Im in Sussex Co. NJ and we are typically are 5 to 10 degrees cooler than the rest of NJ, but it still adds a noticable amount of heat to the house. In the winter, the heat is very welcome.

I'm paying about $200 per ton for my coal so it works out to about $1.20 per day for hot water, less than half what I would pay for propane.

I would not go with an indirect tank when using coal as the heat source, since the minium fire is usually enough to keep the water in the 140 to 150 degree range.

With a Keystoker or Harman, you have about 50 gallons of hot water available, which is plenty for my family.

Hope this helps.

Bill A.
Highlander
 
Stoker Coal Boiler: Harman VF3000 Sold
Hand Fed Coal Stove: Vermont Castings Resolute
Coal Size/Type: Rice
Stove/Furnace Make: Harman
Stove/Furnace Model: VF3000 Stoker Boiler

Re: heating domestic water

PostBy: gaw On: Sun Mar 30, 2008 7:24 pm

I have an old house, cellar walls are stone and 2/3 of the cellar floor is still dirt so this type of cellar will normally be cool and damp. Having the boiler lit all summer is actually a good thing. When temps get a bit higher I will open the basement windows and soon I will turn the aquastat back from 160 to 140. The amount of heat that I feel coming from the boiler during the summer is negligible.

In newer houses or old ones with major insulation improvements you can feel quite a bit of heat in the furnace room during the summer. Newer constructed houses can also be tough to get adequate summer chimney draft. For me I am a believer in burning year round, but if I had a new house or were to build a new one I would consider a few customizations to the house to accommodate this.
gaw
 
Stoker Coal Boiler: Keystoker KA-6
Coal Size/Type: Rice from Schuylkill County

Visit Lehigh Anthracite