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BobC

BobC

Joined on September 15, 2010

Last Post on July 29, 2014

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at least 1/4"

@ March 27, 2011 9:23 AM in Steam Pipe expansion

i don't know exactlyhow far that pipe will expand but I can tell you that a 2" steam main that circles my chimney (about 12 ft long) expands about 1/4" and perhaps a bit more. When cold, the main vent is touching a cold water pipe but when it's full of steam that 2" iron pipe is 1/4" away from the vent.

Bob

What kind of vents

@ March 26, 2011 4:59 PM in Cold steam pipes

It sounds like you have single pipe steam. The pipes and radiators should heat up when the boiler is running. Those bullet shaped things half way up the radiator are air vents. The steam cannot get into the radiator till all the air has left. Can you hear or feel air leaving them when the boiler is making steam? Do all radiators try and heat at about the same time? What make and model are those air vents and do they have an adjustment knob on them?

Put a level on the radiators to make sure they are pitched back towards the input pipe so water can find it's way back to the boiler. You can shim the air vent end up with quarters to get positive pitch if you have to. use a 2X4 to GENTLY lever that end of the radiator up - to much force and you might crack something.

You said you are on the top floor, is there any insulation in the ceiling? If that was removed during the renovation any heat that comes up is just whistling out the top. That ceiling has to have insulation to keep heat in. being on the top floor yo should be getting some assist from the lower floors.

You may need larger radiators to support the bare brick walls because you have probably increased the heating load.

Bob

Nameplate net steam sq ft = radiator sq ft

@ March 25, 2011 8:25 AM in Measuring edr:When to include pick-up

I agree with Mike, match the square feet of steam the boiler is rated for with the square footage of radiation that it is feeding. Also insulate all the piping in the cellar.

Bob

maybe

@ March 24, 2011 5:31 PM in To convert from oil to gas or not?

My old Delco boiler failed in 1996 and i replaced with an oil fired Burnham V75 - after talking with someone who worked for the local gas company who said he didn't see the cost of gas being as low as oil in the near future.

He was right, for about 5 years. In the Boston area right now 140,000 BTU's of gas costs about $2.70 vs the $3.42 my oil dealer is getting. Last year at this time the difference was about 20 cents.

When the Burnham dies I may well replace it with gas fired but it would take FOREVER to make up the costs of replacing a working oil system. I used about 334 gallons of oil last year and have used a bit more than that to date this year.

If the true cost of natural gas is much lower in your area (make sure you know the TOTAL cost of gas - don't believe the gas company), then you have to decide if it's really worth it. Remember you will have to get the oil tank removed and put a stainless steel liner in the chimney to go over to gas.

Bob

GE Hybird

@ March 24, 2011 5:14 PM in Getting the most bang for my buck

A friend of mine installed a GE Hybird (heat pump) hot water heater last spring and was very happy with the drop in his electric bill (vacation home in NH, elec costs about 0.18 per KWH). He calculated that hot water heater would pay for itself in 5 years (it costs about 3-4X what a regular HWH costs) and it's warrantied for 10years so it really was a no brainier for him.

Bob

Check the installation manual

@ March 24, 2011 1:05 PM in Recourse for bad/illegal boiler install....

I'd just like to add that you should check the installation manuals piping diagram to see what he might have done wrong as far as the boiler manufacturer is concerned. If the boiler is not piped per the manufacturers piping diagram, your warranty might be null and void.

Bob

Do your homework

@ March 24, 2011 12:55 PM in Time to replace boiler

Do yourself a favor and measure all of you radiators so you know what the EDR is - EDR is the square footage of radiation attached to the boiler. The number you arrive at will tell you what size boiler you should be installing. The chart I have attached will help you figure out your EDR.

Once you know what size boiler you need you have to select a good installer, this is probably more important than anything else. make sure the installer states (in writing) that he will pipe the boiler in THREADED STEEL per the boiler manufacturers piping diagram as a minimum. If he goes over and above great, but make sure he follows the manufacturers diagram so the new boiler works quietly and efficiently.

If the installer balks at this, show him the door and find someone else.

Bob

I agree, oil not burned is the best kind

@ March 23, 2011 8:20 AM in To upgrade or not?

Jack,

I retired a couple of years ago and wanted to keep my heating bills reasonable. My quick solution was to keep the hallway doors closed downstairs so the heat would not go upstairs (3 bedrooms) when i was downstairs (living room, dining room, and kitchen) and to use a quartz heater as aux heat in the living room as I read or watched TV after supper. I want to keep my 15 year old Burnham V75 running just as long as I can

I have also looked into installing a split heat pump system both to use as heat for the shoulder months (keeping the oil burner off) and for cooling on really hot summer days. I actually find I use the AC less now that I've retired because i can keep the windows open in the morning to get the cool breeze. Living a block from Quincy Bay does have it's advantages - at least in the summer.

Bob

Chart

@ March 23, 2011 8:01 AM in sizing a boiler

You will have to make a chart that lists the square footage of all the radiators in the place. With any luck most of the apartments are very similar in the number and types of radiators that they contain. Don't forget to add radiators in any common areas; hallways, lobbies,etc.

When you add up those numbers that will give you the total number of sq ft; you then want a boiler that can feed that number of sq ft.

Use the chart I've enclosed to figure out the sq footage of each radiator.

Bob

How to check

@ March 21, 2011 12:20 PM in loop under the pressuretrol

How is the system working now? Is there more hissing or banging?

On a normal cold day it is not unusual for a steam system to cycle on pressure. That means the system will run until it hits the upper pressure set point and then turns off, after a couple of minutes the system turns back on again until the pressure rises to that upper set point. This goes on until the thermostat is satisfied.

If you suspect the pigtail is clogged you have to remove the pressuretrol and see if you can blow into the open pigtail pipe, make sure the circuit breaker to the boiler is off and that the boiler is not hot. There will be some resistance because of the water in the pigtail but you should easily be able to overcome that. Also if you look at the brass fitting on the pressuretrol \you will see a small (1/16") hole at the base of the brass fitting, that has to be clear.

Post some pictures of the pigtail and the pressuretrol so we can see what your dealing with.

Bob

Settings

@ March 21, 2011 8:12 AM in Hissing and Gurgling

That's a picture of my setup and it is currently set for a 12 oz cut out and a 4 oz cut in.

I also have a small house, the EDR (sq footage of all the radiators) is about 190 sq ft. I do have some short cycling issues because the 15 yr old boiler is over sized but the system is otherwise efficient and relatively quiet.

Bob

Might be a light at the end of the tunnel

@ March 20, 2011 12:48 PM in Japan Nuke plants

I meant to state that the PWR type of reactor might have been a poor choice for seismically active areas near the ocean. Of course we have to deal with what we have not what we wish we had.

I think this disaster will make people look at what might be required to retrofit these older designs so they can be made safer in the event of power to the cooling systems being cutoff for extended periods.

All industries get blind sided by disasters like this, you can't protect against any conceivable event and still remain practical. From what I've read today in the WIKI article I think they are pretty much on the road to getting the cooling pond problem under control. Next they have to figure out how to control that one reactors cooling and then there is the question about entombing the destroyed reactors and finding a rational way to handle the nuclear waste (we in the US are guilty on that front).

As you stated, hopefully this can be done without any large scale release of radioactive material.

Bob

Light water reactor poor choice?

@ March 20, 2011 11:04 AM in Japan Nuke plants

Out of options
A surprising culprit in the nuclear crisis
By Leon Neyfakh

March 20, 2011

As the nuclear crisis in Japan unfolded last week, experts scrambled to understand why things were going so horribly wrong. While no one was surprised that a 9.0 earthquake and a massive tsunami had caused severe and complicated problems, critics charged that various aspects of the Fukushima Daiichi plant’s design had made the catastrophe more perilous than it had to be. Some considered the particulars: Why had the cooling system’s backup generators been installed in a way that left them vulnerable to the tsunami? Why did the reactors use a cost-saving containment vessel whose disaster-worthiness had been repeatedly questioned by scientists? Why had the pool of spent fuel rods overheated?
   
For those taking a longer view, however, there is a larger question looming over the disaster: Why was Japan, a nation at high risk for earthquakes and natural disasters, using a type of reactor that needed such active cooling to stay safe? And the answer to that doesn’t lie with Japan, or the way the plant was built. The problem lies deeper, and concerns the entire nuclear industry.

Japan’s reactors are “light water” reactors, whose safety depends on an uninterrupted power supply to circulate water quickly around the hot core. A light water system is not the only way to design a nuclear reactor. But because of the way the commercial nuclear power industry developed in its early years, it’s virtually the only type of reactor used in nuclear power plants today. Even though there might be better technologies out there, light water is the one that utility companies know how to build, and that governments have historically been willing to fund.

Economists call this problem “technological lock-in”: The term refers to the process by which one new technology can prevail over another for no good reason other than circumstance and inertia. The best-known example of technological lock-in comes from the 1970s, when VHS and Betamax, two different kinds of videotape, competed in the market until VHS gained a slight lead and then leveraged it to total domination. Whether the VHS format was actually superior to Betamax didn’t matter. After the lock-in, consumers no longer had a choice.

Much more is at stake in nuclear power. Some reactor designs are safer than others in an accident; some are more efficient than others in their use of fuel and produce less nuclear waste. The fact that the industry settled on light water over any number of alternatives was determined in the years after World War II, when the US Atomic Energy Commission and Navy Admiral Hyman Rickover made a series of hasty decisions that irreversibly set the course for how nuclear power plants around the world are built today.

“There were lots and lots of ideas floating around, and they essentially lost when light water came to dominate,” said Robin Cowan, a professor at the University of Strasbourg and the University of Maastricht who wrote a 1990 paper in The Journal of Economic History about the nuclear industry’s technological stagnation. “The market tends to choose a dominant design before it’s optimal, and it tends to under-explore.”

The fact that light water was used in the first American nuclear power plant in 1957 made it that much more likely that subsequent nuclear plants in the United States and around the world would use it, too, as utility companies decided, one after another, that it was in their best interest to use a well-established reactor technology instead of trying something more experimental. The result was that many potentially viable proposals — including plants that, in an emergency, wouldn’t have depended on the diesel generators that failed at Fukushima — were stifled before anyone could properly evaluate them.

Lately, concerns about fossil fuels have brought new enthusiasm for nuclear power, and led scientists back to the task of inventing new and better types of reactors. But even as innovators succeed at securing funding and attention for their research, the power of technological lock-in still hovers over the practical questions of who will design and build them. As the catastrophe in Japan inspires a new reckoning with the benefits and perils of nuclear energy, the industry’s lock-in will need to be part of the discussion.

When nuclear fission was initially harnessed for energy, its first successful use was not in power plants, but in submarines. After the conclusion of World War II, the Navy wanted a submarine fleet that could stay underwater for long periods of time without having to come up for fuel. The key would be nuclear energy. In 1946, Rickover was put in charge of figuring out what kind of reactor should be used in these submarines.

Rickover had several kinds of reactor designs to choose from besides light water, which at the time was the exclusive domain of the American manufacturing giants Westinghouse and General Electric. The most significant differences among them had to do with the materials used to cool their cores and to moderate the fission process. The so-called heavy water reactor, developed in Canada, used a coolant based on a different isotope of hydrogen from that in normal water. (Light water is just normal H2O.) Gas-cooled reactors, meanwhile, which had their origins in Great Britain, did not use liquid coolant at all. The breeder reactor, developed by General Electric, relied on liquid sodium as a coolant.

Each one had its advantages. The sodium-cooled breeder reactors were more economically efficient; the gas-cooled reactors took longer to get hot, and would probably not melt down as quickly if their power failed. But Rickover’s choice ultimately came down to size. “He needed a reactor that would fit inside his submarine,” said Charles Forsberg, executive director of the MIT Nuclear Fuel Cycle Project. Because reactors built with light water technology could be much smaller than any other kind, Rickover decided they were the Navy’s best bet.
At that point, the nuclear power industry was still anyone’s game. Though Rickover’s decision certainly gave Westinghouse reason to be optimistic about the future of its light water technology, it did not discourage the Canadians from pursuing heavy water nor the British from pursuing their gas-cooled systems. In fact, there was a brief window when it looked like the British had a big win on their hands with the completion of the world’s first commercial nuclear power plant in August 1956. But as it happened, the Americans were right behind them: A little over a year later, the first US nuclear plant went live in the town of Shippingport, Pa. It was a light water plant.

It had not been a foregone conclusion that Shippingport would be powered by light water technology. In fact, according to Cowan, some of the nuclear physicists on the US government’s payroll at the time insisted that they had not done enough research on light water to conclusively declare it was the best option available. But a few factors tipped the scale. First of all, Rickover was in charge of overseeing its construction. And the US government considered it a matter of national security to get the plant built as quickly as possible, in order to send a swift signal to the Soviet Union and the rest of the world about America’s technological supremacy. Light water was familiar, domestic, and the most likely to work immediately.

“We were competing with the rest of the world, trying to become leaders in nuclear technology, and we wanted to quickly, without straining the budget, build some demonstrations,” said Ashley Finan, a PhD candidate at MIT’s department of nuclear science and engineering who has been studying the history of innovation in nuclear technology since World War II. “The reactors that were most available were the light water reactors, so that’s what we used.”
It was after Shippingport that light water truly took off, as both Westinghouse and General Electric — which had focused all of its resources on developing water reactors after some early experiments with breeders — made an aggressive push on behalf of the United States for dominance of the global market. “They knew there were other technologies in the wings that might be better,” said Cowan, whose paper on the rise of light water technology was recently featured on the economics blog Marginal Revolution.

By 1970, according to Cowan’s research, light water had been adopted by every major consumer of nuclear power in the world except for Canada and Great Britain, who were at that point still trying to make a go of heavy water and gas-cooled, respectively. According to Finan, the federal regulations in the United States essentially assumed that plants would use light water technology, making it extremely difficult for any other type of plant to get clearance at all.

By 1986, more than 80 percent of all nuclear reactors in the works around the world — excluding the Soviet Union — were of the light water variety. Japan’s reactors were built in the 1970s based on light water designs by General Electric, Toshiba, and Hitachi. Today, the vast majority of all nuclear power plants around the world — and all 104 operating commercial reactors in the United States including the Vermont Yankee plant and the Pilgrim Nuclear Station in Mass. — use light water technology.

Light water may have been — and may still be — the best option available. Certainly the technology has been refined since its early days, and newer reactor designs have advanced safety features that partly address the cooling problems suffered in Japan. But the trouble with technological lock-in is that you never really know: With only one choice, it’s impossible to tell whether you might have been better off with one of the early alternatives.

“Once the bandwagon gets rolling and starts to accrue advantage, it tends to get more advantage,” said W. Brian Arthur, the economist at the Santa Fe Institute who introduced and coined the concept of technological lock-in in the early 1980s. “Even if it’s not the best to start with, if it just gets ahead by chance, then it tends to get further ahead because of all the advantages.”

As soon as one technology gets a significant leg up in the competition, it becomes extremely difficult for rivals to derail it. Apart from the VHS-Betamax competition, the effects of lock-in can be seen in the dominance of the QWERTY configuration of keyboard letters, and in the victory of internal-combustion automobiles over Stanley Steamers in the early 20th century.

In the nuclear industry, more experimental approaches were decisively frozen out before their merits could be properly tested. A good example of this happened in the mid-’70s, when an American company called General Atomics tried to break into the market with a type of “high temperature” gas-cooled reactor that could cool itself in an emergency using the natural circulation of air instead of relying on motor-powered pumps and valves. One might have thought this cooling system would be seen as a major achievement — and certainly, a useful option for sites like Japan, where there’s a high risk of natural disasters knocking out a power supply. But of the seven high temperature graphite-gas-based power plants that General Atomics had been contracted to build by 1976, all but one ended up being canceled.

“One of the, let’s say, challenges in nuclear technology is that the plants are expensive and owners are usually risk-averse,” said Mujid Kazimi, director of MIT’s Center for Advanced Nuclear Energy Systems. “Part of it, also, is that it takes a long time to get a license for a new reactor concept. If you have a new idea and you want to eventually get it into the market, you need a license, and that can take years.”

Ultimately, experts say, overcoming technological lock-in requires the deliberate participation of the federal government, at least by partnering with private companies and university researchers trying to introduce new ideas. Trying to disrupt a locked-in technology is an extremely risky proposition, and in most cases, it’s too tall an order for a single company to take on alone. As Arthur put it, “If everybody’s clapping to one beat and you try to start clapping to a different one, it’s a little hard to take over. It can be done, but you need a whole bunch of people and it needs to be loud.”

There are signs that that’s starting to happen. Over the past decade or so, concerns about climate change and fossil fuel dependence have led to something of a renaissance for the nuclear industry, which has started to look into new ideas that don’t involve light water, and some that do. In 2002, the US government unveiled an initiative aimed at helping private companies develop and bring to market new nuclear technologies. And according to Finan, the federal regulations that are used to license new nuclear technology in the United States are in the process of being rewritten so that they don’t favor light water reactors as heavily as they used to.

Meanwhile, a number of promising projects are underway around the world. Toshiba is working on a sodium-based breeder reactor. The Department of Energy is working with General Atomics and Westinghouse on a high-temperature gas-cooled one. In India, there are plans for a reactor that uses thorium and molten salt. Meanwhile, several manufacturers are exploring designs for so-called modular reactors that could radically change the industry — and make it friendlier to innovation — by allowing utilities to build small plants and expand them as necessary instead of going all in with a multibillion dollar investment right away.

Whether any of these ideas catches on will depend in part on the industry’s willingness to take risks. It will also depend on circumstances, though, just as it did back in the 1940s when light water first emerged. As the nuclear industry comes to grips with the tragedy in Japan, experts hope that one effect will be to encourage a rare, concerted push that forces a locked-in market to open up again.
“There are certainly innovative reactors available to be developed that have safety features we would value,” said Finan. “I hope we’ll see a more open-minded approach.”

Leon Neyfakh is the staff writer for Ideas. E-mail lneyfakh@globe.com.
© Copyright 2011 Globe Newspaper Company.

New is nice

@ March 19, 2011 4:40 PM in To upgrade or not?

With a hot water system you have lot more options to control the system than you do with steam. i know what you mean about starting out with everything new, even then I'd try to keep things simple for a small residential system. If push comes to shove it's nice to be able to revert back to a simple go-nogo control system if something fancier gets balky - ask those poor bastards working on that nuke in Japan..

The EDR rating of My boiler is almost 3 times the radiator sq footage. I've reduced the firing rate to 1.1gal/hr vs the rated 1.65 so that's about as far as i can go down that road. It would probably take 20 years to make it worth my while to replace the boiler unless it dies.

I guess I could offer to sell steam to the neighbor.

Bob

Well done!

@ March 19, 2011 4:28 PM in Degree days, Energy use

That's great news! I'm glad all your hard work paid off.

I'm still trudging down that same road. the steam system is reasonably happy and now I have to figure how to properly insulate an old new england cape (front and rear dormers) that has walls that are almost impossible to reach and insulate.

Bob

has to be done right

@ March 17, 2011 3:25 PM in Peerless boiler install

That boiler will not work right until it is piped per the install manual. If the guy who installed it won't respond it might be time to contact Peerless and ask them if this install will affect your warranty.

Bob

Good teacher

@ March 17, 2011 8:38 AM in steam issue

For the last bit of my working life I worked for the post office as a technician (old job went to China) on the mail sorting equipment. The PO sends you to schools on the equipment where you spend 2-10 weeks learning how the machine works. then you go back to your plant and figure out how it REALLY works.

More than once the boss walks up and asks whats wrong with the machine AND why are up here when the problem is at the other end of the machine (150 ft long). I told him the symptom was down there but the problem that caused the symptom was up here; at that point he walks away mumbling to himself.

Mr Fawcett taught you a valuable lesson by teaching you to look at the whole system.

Bob

GE mark 1 reactor problems

@ March 16, 2011 9:14 AM in Japan Nuke plants

DEVASTATION IN JAPAN

Warning was issued in ’70s on GE-designed reactors
By Tom Zeller Jr. New York Times / March 16, 2011

NEW YORK — The warnings were stark and issued repeatedly as
far back as 1972: If the cooling systems ever failed at a
Mark 1 nuclear reactor, the primary containment vessel
surrounding the reactor would probably burst as the fuel
rods inside overheated. Dangerous radiation would spew into
the environment.

Now, with one Mark 1 containment vessel damaged at the
embattled Fukushima Daiichi nuclear plant and other vessels
there under severe strain, the weaknesses of the design —
developed in the 1960s by General Electric — could be
contributing to the unfolding catastrophe in Japan.

When the ability to cool a reactor is compromised, the
containment vessel is the last line of defense. Typically
made of steel and concrete, it is designed to prevent — for
a time — melting fuel rods from spewing radiation into the
environment if cooling efforts fail.

In some reactors, known as pressurized water reactors, the
system is sealed inside a thick steel-and-cement tomb. Most
nuclear reactors around the world are of this type.

But the type of containment vessel and pressure suppression
system used in the failing reactors at the Fukushima Daiichi
plant is physically less robust, and it has long been
thought to be more susceptible to failure in an emergency
than competing designs. In the United States, 23 reactors at
16 locations use the Mark 1 design, including Pilgrim 1 in
Plymouth, Mass.; Vermont Yankee in Vernon, Vt., and the
Oyster Creek plant in central New Jersey.

GE began making the Mark 1 boiling-water reactors in the
1960s, marketing them as cheaper and easier to build — in
part because they used a comparatively smaller and less
expensive containment structure.

US regulators began identifying weaknesses very early on.

In 1972, Stephen Hanauer, then a safety official with the
Atomic Energy Commission, recommended that the Mark 1 system
be discontinued because it presented unacceptable safety
risks. Among the concerns cited was the smaller containment
design, which was more susceptible to explosion and rupture
from a buildup in hydrogen — a situation that may have
unfolded at the Fukushima Daiichi plant.

Later that same year, Joseph Hendrie, who would later
become chairman of the Nuclear Regulatory Commission, a
successor agency to the atomic commission, said the idea of
a ban on such systems was attractive. But the technology had
been so widely accepted by the industry and regulatory
officials, he said, that “reversal of this hallowed policy,
particularly at this time, could well be the end of nuclear
power.’’

In an e-mail yesterday, David Lochbaum, director of the
Nuclear Safety Program at the Union for Concerned
Scientists, said those words seemed ironic now, given the
potential global ripples from the Japanese accident.

“Not banning them might be the end of nuclear
power,’’ said Lochbaum, a nuclear engineer who spent 17
years working in nuclear facilities, including three that
used the GE design.

Questions about the design escalated in the mid-1980s, when
Harold Denton, an official with the NRC, asserted that Mark
1 reactors had a 90 percent probability of bursting should
the fuel rods overheat and melt in an accident.

Industry officials disputed that assessment, saying the
chance of failure was only about 10 percent.

Michael Tetuan, a spokesman for GE’s water and power
division, staunchly defended the technology this week,
calling it “the industry’s workhorse with a proven track
record of safety and reliability for more than 40 years.’’

Tetuan said there are currently 32 Mark 1 boiling-water
reactors operating safely. “There has never been a breach of
a Mark 1 containment system,’’ he said.

Several utilities and plant operators also threatened to
sue GE in the late 1980s after the disclosure of internal
company documents dating to 1975 that suggested the
containment vessel designs were either insufficiently tested
or had flaws that could compromise safety.

The Mark 1 reactors in the United States have undergone
modifications since the initial concerns were raised. Among
these, according to Lochbaum, were changes to the
doughnut-shaped torus — a water-filled vessel encircling the
primary containment vessel that is used to reduce pressure
in the reactor.

Keep it simple

@ March 16, 2011 8:59 AM in To upgrade or not?

My 15 year old Burnham V75 steam boiler is working fine and has been very reliable (one service call in 15 years). When it does die I'll replace it with the right size boiler with simple controls. The complexity of some of the very efficient models make me wonder about their long term reliability.

Steam heating systems can be as simple as anything can be, don't screw it up by adding a lot of unnecessary electronics on top of it.

I believe a lot of the problems they are having with the reactors in Japan is because they rely on automated systems that don't work without external power. Those systems should have been designed so they could sit forever in a quiescent mode, with no external power for pumps, etc. That means a large convective cooling setup that could dissipate the heat from the reactor.

Bob

Btu per

@ March 15, 2011 11:02 AM in Sq ft of steam to btu conversion

240 BTU per cu ft of steam.

Bob

Still have it

@ March 12, 2011 11:27 AM in Deadmen

I still have the carcass, saved it for the tubes and the transformer.

if you need any parts just let me know.

Bob

fan

@ March 12, 2011 11:21 AM in Deadmen

I've seen 6" muffin fans used for them. New ones are pricey so try to pick up something at a surplus house.

I was a calibration tech early in my career and the Tektronix scopes were built like battle ships. The tubes lasted for a decade even when they were operated 40 hrs a week. I've read articles that describe the design process and it really waas state of the art.

Bob
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