Fuel usage and steam??

Toddid Goldsmith's

ERIC I ASSUMED YOU ARE THINKING ABOUT A NEW SYSTEM. IF I WERE YOU I WOULD INSTALL A LOW WATER VOLUME HOT WATER SYSTEM.THEN TAKE THE SAVINGS TO THE BANK.

Eric L._3

Fuel usage and steam??

I have been keeping track of my fuel consumption the last 2 seasons here in NYC. Been seriously considering converting my WM SGO-7 2GPH over to water from steam in preparation to replace it with a MODCON. Last year during the heating season (OCT-MAY) I used 859 gallons and this year from Oct-present I have used 1077 gallons (More degree days this year). My house is 2800sqft of living space heated by about 680EDR with a Slantfin heatloss of 88000 BTU.I guess my question is does my fuel usage fall in line with normal? What if any advantage would I gain switching to hot water and later upgrading to a MODCON? Thanks

I forgot to mention that my DHW is a tankless coil and there are 9 people who live in the structure so I realize some of my usage is from that.

Eric L.

TODD WILHELM

HOT WATER VS. STEAM

WE HEAT OUR HOUSE WITH HOT WATER. WE LIVE IN NAPANOCH,N.Y., ABOUT ONE HUNDRED MILES NORTH OF NEW YORK CITY.THE DOMESTIC HOT WATER IS HEATED WITH A TANKLESS COIL WHICH ALSO SUPPLIES HOT WATER TO MY WIFES BEAUTY SALON. AT 0 TEMPS. 180 DEGREE BOILER TEMPS. DO THE JOB JUST FINE. IT TAKES A LOT MORE ENERGY TO BOILER WATER, THAN IT DOES TO HEAT IT TO 180 DEGREES. I'VE SEEN CONVERSIONS FROM STEAM, TO HOT WATER, SAVE AS MUCH AS 50%. THE LOWEST WATER TEMPS.,AND SMALLEST WATER VOLUME YOU CAN USE TO GET THE JOB DONE, THE MOST ECONOMICAL. WHY SPEND EXTRA MONEY TO MAKE IT BOIL,WHEN JUST MAKING IT HOT WILL WORK FINE

Eric L._2

Thank You

for your input.

Eric l.

Steamhead (in transit)

What Todd didn't tell you

is-

1- Assuming that both systems are in good repair and the boilers are similar, a steam system can equal the comfort and approach the efficiency of hot-water. There is much less water in a steam system to be heated.

Each and every comparison I have seen of distributing BTUs by steam as opposed to hot-water has involved a steam system with ancient boilers, blown traps, bad venting, no insulation, control problems, I could go on and on.

They compare this to a brand-new hot-water system. This is not, never was and never will be, a true apples-to-apples comparison.

One recent alleged "comparison" was in a school system where the steam systems were about to expire from sheer neglect. This is typical of school systems- no one wants to fix anything, "costs too much". With this kind of neglect, a mod-con will be very troublesome and will likely die an early death. There's no way around it- mod-cons need a higher level of care than atmospheric boilers.

2- Converting a steam system to hot-water involves considerable risk. You're increasing the system pressure at least ten times. Steam systems in good repair can circulate steam at a few ounces pressure and should never need more than 2 pounds on the coldest day of the year. A hot-water system in a 2-story building needs 12 pounds to get the water to the top floor. A 3-story building needs 18 pounds and so on.

This increased pressure WILL do a great job of finding weak spots in piping and radiators. I've seen buildings that were severely damaged from these leaks, one was a beautiful old church that looked like the devil had rampaged thru it.

Bottom line: My company (of which I am half owner) does not recommend or perform these conversions, and will not work on a system someone else has converted unless we change it back to steam. We don't need the liability.

So how do we get your system to run better? Start with the boiler. Your SGO is oil-fired and we don't know how well it's been maintained. Some knuckle-dragging oil company employees don't clean boilers well (if at all) so if your boiler is dirty, having it properly cleaned and tuned will save much. The burner used in this boiler should not produce any smoke or soot whatsoever. If it does, something is wrong. The flue passages should be clean enough to eat off of.

Given the radiation count and the fact that your boiler has more capacity than needed, I'd also suggest down-firing the boiler from 2 to 1.75 GPH. This should make it turn off and on less frequently during a run.

Once the boiler has made the steam, its job is done. From that point, the system must move the steam to the radiators so it can give up its latent heat. One common problem in this area is improper venting of air from the system- details vary depending on what type of steam system you have. Another is pipes that are not insulated.

And remember, a mod-con boiler cannot be exhausted thru a standard chimney. Local Codes may also restrict where or if you can vent this type of boiler.

Tell us more about your system. For starters, are there two pipes or just one connected to each radiator?

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ttekushan_3

Steamhead,

HERE WE GO AGAIN. oh. sorry. Here we go again. I give you great credit for your persistence on this subject but frankly (no pun intended), I've grown weary of repeating myself over and over.

You've gotten the occasional 50% fuel savings on updating steam system control and venting (let alone competent maintenance) with 30% or so being typical. I've gotten the same results myself. And so has Gerry Gill. And so has BoilerPro. Etc.

Hydronic heating theory has now been taken over by hot water purveyors who insist on evaluating the steam medium with delta T's and flow rates. Obviously you can't do this when dealing with a latent heat medium any more than you can use those measures to understand a refrigeration system. Yet its done, without irony.

Boiling water is described as if you are boiling the thousand gallons of water in a hot water system. Of course this isn't true, yet its done...

The lower delta T's from heat exchanger to water in steam systems are taken alone without any acknowledgment that an even greater delta T exists from radiator to air. Or that continuous circulation isn't necessary on steam because steam is a one way transaction. It never returns as steam, so it does all its work in one step. The circulation of steam is assisted by the condensation and latent heat recovery itself. The cost of circulation is nil. "All that energy" used to boil water (a tiny fraction that in a hot water system) is used to heat the living space and distribute the heat energy with little loss.
Yet these critical items are all removed from the analysis because water doesn't work that way. And this is accepted by the industry, without irony.

We are told that the pipes lose more heat with the higher temperature of steam. So I suppose this heat is sucked directly into outer space somehow and is therefore a "loss." Most heating pipes I've seen go through the heated space. Hmmm. Yet this is how its now viewed by the hydronics industry.

Is this is why district heating systems all over the U.S. and Canada are steam --and being expanded upon? I suppose that the loss of total enthalpy on a 125 psig steam main of 1% per mile can be improved upon by rewriting the laws of thermodynamics. Though it appears that this is now acceptable as far as heating systems are concerned.

It never occurs to people that a small fraction of the expensive myriad of controls required to get efficiency from hot water systems could do the same for steam. Of course, viewing the round hole of steam control with the square peg of hot water controls makes it appear as though its not possible to control steam. An entire industry is blind to how easy and inexpensive (maybe thats part of the problem) it is to balance and modulate a steam heating system.

And to think that owners of steam heating systems could take full advantage of such things in addition to having an energy star steam boiler installed for a small fraction of the cost of a conversion to hot water. Here the property owner benefits greatly in fuel savings with the minimum cash outlay for the savings achieved.

Yet the hydronics industry tells property managers and homeowners that the only way to save is to do a costly conversion to hot water complete with costly controls, boilers, valves, etc. Unfortunately the costs versus the savings in this scenario are not nearly as favorable to the customer as refreshing the steam system.

And who, then, is laughing all the way to the bank?

I suggest that people search the Forums here for these subjects. The issue has been thoroughly discussed and analyzed in terms of cost/benefit and perhaps more importantly in terms of "embodied energy" within the life cycle of the typical steam system components and that of modern hot water system components.

Google "embodied energy" to learn more.

Terry Tekushan
Efficient Steam

P.S. Flue gas latent heat recovery is another issue altogether. There are a growing number of energy star steam boilers available today, with more coming down the pike. However, none of those available in the U.S. are condensing models. Condensing hot water boilers are available at extra cost. I won't dare question the added cost (in both dollars and corrosion sensitivity) vs payback lest I be shot down by the self righteous who I'm told care more about their children's future than I do [this has happened to me here].

Finally it is totally erroneous to state that flue gas heat recovery can't be done with steam boilers. In fact, its done routinely in industry, but these economizers, condensing economizers and flue gas condensers are all discrete units that are not considered as part of the boiler since they are not "built in" to the boiler. These devices are not currently available as part of space heating steam boilers (or even separately as far as I can tell) since it appears that the cost of such things have a long payback period.

Tim Weaver

Heating degree days

Thanks folks for your comments. Eric, I'm also in NYC. Live in a highrise with Con Ed steam. Would you mind sending me your heating degree data. I would like to compare it to the information on our Con Ed

Tim Weaver

Heating degree days

that was smart. Eric the email address is mpsoutin@yahoo.com

Boilerpro_5

You've nailed it, Steamhead.....

I agree with Steamhead in his analysis, and, for those that may think I am a partial to steam,  I have converted a number of steam systems to hot water after careful review how the systems relate to the structures needs and the condition of the system.  The chief systems I convert are convector type systems due to the fact that most are inherent instant on/ instant off heating that nearly duplicate the many disadvantages of forced air, but without the extremely short equipment life. Other sysetms I convert are systems in structures where the heat loss has been dramatically reduced so the heating plant size is radically different from hot water to steam (mainly in one pipe systems, two pipe systems can be modified for smaller boilers) or  a good deal of the piping needs replacement anyway due to abuse or hacks.  Cast iron radiator systems usually don't have most of these problems in most buildings, because they inhernetly modulate the heat and deliver a large percentage of this heat in the form of more efficient radiation, especially tow pipe steam and vapor systems.When you consider all the costs of a hot water system, including pumps, electrical usage, more controls, etc, the operating cost for the two systems is much closer than most would believe, when comparing typical cast iron systems.Boilerpro

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jp_2

what savings?

by the time you install a completely new system, what is there left to save? wouldn't there be more savings if you got the existing system running as well as it can? say, maybe $10,000?

by the time you have broken even, time for a new boiler.

what you fail to mention in your first post is that extra energy to get from 180-212F is the energy used to heat the house. where inefficiency comes in is the energy needed to keep that water near steam capability, so insulate lines well.

joe lambert_2

Fuel usage for steam

I agree with steamhead. I've lived with Forced hot air, forced hot water, and now steam. When I first bought the house the gas bills in January and February were about $600 a month with the old snow man and a gas conversion burner. After I improved the envelope and completely tuned up the system the following year it was hovering around $280 during the same months. After installing a new Weil McLain EG 40 the Gas bill has never broke $200 and that includes our hot water which is from a gas hot water tank. Depending on the year and the cost of gas for that year it costs me from $1000-$1200 for the year in heating and hot water with three people living in the house. The house is 1500 sq ft and I have 315 sq ft of radiation with a slant fin heat loss of just under 39000 btu using an outside temperature of 0 degrees and a inside temp of 70.

My point is that steam systems can be made as efficient compared to standard cast iron forced hot water hydronic systems and that the 80 year old one pipe steam system I have is living proof of this. I also live in Massachusetts were the degree days I'm sure are longer than in NYC.

Dollar for dollar the best bang for your buck would be to lower your heat loss with more insulation and weather stripping in key areas along with tuning that steam system to run as efficiently as possible.

An example of this is with a friend of mine who bought a house with electric heat. During his first heating season his electric bills were near $700 for his 1700 sq ft house during January and February. I suggested to him that he add more insulation in the attic area and he did. The insulation cost him about $250. Since then his electric bills have not gone over $500. He got his money back in less than two months!

Eric L._2

Single pipe

My system is a single pipe and could you expand on reducing the nozzle size? Thanks

Eric L.

Steamhead (in transit)

Eric, a pro must do that

but it can be done as part of a clean-out and tuning.

The nozzle is mounted inside the large tube that goes from the burner chassis to inside the boiler. It receives oil at high pressure (at least 100 PSI, probably higher on your unit) and creates a fine spray that an electric spark can ignite. This explanation is very oversimplified but it should give you an idea of what's going on in there.

Each year, the boiler should be inspected, nozzle and filters replaced, safety controls tested, flueways cleaned if needed (and as I said earlier they should be CLEAN after a year's operation) and proper, safe, efficient combustion verified with a digital analyzer. This work can only be done properly by a qualified professional, and should be done on all heating units regardless of type.

To reduce the firing rate, a nozzle of a slightly lesser capacity is installed. The proper nozzle specifications depend on the type of boiler and burner involved. A real pro will have the manufacturer's OEM specifications to refer to.

Click on Resources at the top of the page, then Find a Professional to locate a steam man near you.

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Eric L._2

WOW

Sometimes you get what you ask for huh? One hell of an answer from all you guys. I appreciate your patience and your council. I think I will keep my steam for now at least and see how far I can take it . I'm going to see if I get ahold of Al Corelli since he's in my area for a good tune up and a downfire as Steamhead suggested. Thanks Again everyone.

Eric L.

K HAYNES

IF YOU WANT TO SAVE FUEL SCRAP THE TANKLESS AND GO WITH AN INDIRECT HOT WATER HEATER. ESPECIALLY WITH 9 PEOPLE IN THE STRUCTURE. THIS WILL SAVE YOU FUEL COSTS ESPECIALLY IN THE SUMMER

mike jones_2

heating degree days

we're also in nyc and would be happy to try and dig out our data on our gas usage vs. hdd. keep in mind that united states hdd data is way oversimplified.

new smith steam boiler this past november.

also, importantly, does anyone know a better measure than standard hdd heating degree days. we were shocked to learn that the industry simply averages hi and lo temps. ie - if a day has a hi of 40 degrees and a low of 20 degrees they call it a 30 degree day while most of us would probably agree that there are plenty of these days in ny were the true average was far closer to 20 degrees. just becuase the sun blasts for a few hours at noon doesnt make the 24 hour cycle heavily influenced by a 40 degree hi.

i have been shock that our meteorologists have not learned to use computers that can average more than 2 numbers per day. the raw data exists at the national weather stations, but we are still searching for any schools or industries that actually run the math. we have not even heard any defensive reasons why not to run the data. some people would rather beleive the earh is flat than dig deeper.