The right tool for the job

Henry_4

I have decided to lay a few comments on the table about boiler selection. I have been wrapping my mind around this for over a week now and finally have determined to put it into play.
Is there a perfect boiler, no. Are there perfect systems, no. But I can make a strong case for why a Viessmann Vitodens is the best choice in wall hung systems. I can also make a strong case for why a Weil or a Burnham or any other number of boilers are good choices for the projects that we work on. Now, to borrow the thoughts of Charlie Daniels, if the devil knew how hot Johnny was on the fiddle, he woulda kept on walking. My point, I can put my products against any other system, and debate the merits of mine over anyone. Sun Tzu is very pointed when he states knowing your competitors is as important as knowing yourself.
Am I going to get every project, no. Am I going to tell Hotrod, ME Paul Polletts or Steve Ebels how to set up a job, no. I can explain the merits of Viessmann to them, but I will never force them to drink form the pool of silver. Is that bad and have I failed to enlighten, again, no. The point is, it is up to the guys putting the systems in to make them as good as they can be. I can promise anyone that works with me though, you work with mine, I can tear it apart and rebuild it and will be right there with you when you are learning your way.

Furthermore, I once had a boss that said, Henry, if the only tool in your belt is a hammer, then the whole world is a nail. I am so glad that I have so many selectable options for the projects that I work on. A man is a fool if he does not take as much training as possible when working on these systems, because quite frankly, knowledge is power. The things that I have learned from the people at Viessmann would blow your mind. The flexibility afforded by water, the ability and benefit of continuous dynamic reset of flame and output temperature, the benefit of reseting to temperatures that would destroy so many boilers. Again, there is merit in the Viessmann way. I am not so arrogant to say that Viessmann is the only way and anyone else is junk. I would counsel others from saying that. But why would anyone turn their back on a product just because it is the "snooty-falluty" boiler from Germany is way beyond me.
If you have had bad experience with the product or it is not adequately serviced in your area, fine. But if you need an answer and haven't been able to get one, email me. Scouts daddy in "To Kill A Mocking Bird" said never judge a man until you have walked a mile in his shoes. Good advice, don't judge any system until you understand it. At the same time, let me weight the merits of what V can do, you owe it to yourself to check it out. Fail to be persuaded and you have educated yourself a little and will better understand what it is you are trying to do. Maybe, just maybe, you find a better way for some of your applications. Maybe not every job, but then sometimes a hammer is to violent and a screw driver might work.

If you read this, thanks, I remain commited to the fact that Viessmann is the tool you should be using.

Good luck,
Henry

eleft_4

tools for the job

Henry,

my Dad's name is Henry and you seem to have a similar out look in making a technical choice. It's kind of like playing chess, you look all around before you make your move. I keep looking around also, so many things out there. So many stories, I like yours.

al

Wethead7

We understand

Myself and HotRod live in the midwest. The perferred method of heating is scorched air. We have to be very cost competative. The other problem is the local supply houses do not stock very much high end equipment. This makes part extremely rare and hard to come by. The firm I work for stocks a deeper parts inventory, than most of our suppliers.

We are looking at the big orange now. The problem is no local supplies.

Your point is well taken.

Mike

Heatermon

Ditto from the West Coast

But besides supply, support after the sale is equally important. We use several competing manufacturer's products, chosing the "best" one for the job at hand. However, before we commit to any product, we are bound and determined to verify what problems may occur (and we eliminte ANY manufacturer who claims "We haven't had ANY problems at all with our products"). We then "require" our supplier to STOCK the replacement parts that WE feel are necessary to "protect" OUR CUSTOMERS' investment and OUR REPUTATION. At the very least I want a supplier who'll give us the "control module off his back" to get a customer up and running again. This takes alot of effort on both the manufacturer and the supply house, but is well worth the "hassle" to get OUR business. I have an intrest in these "high end" Viessman products, but untill there are knowledgeable and well stocked dealers in my area (San Diego) I will be sticking what is working for us (Rheem, Raypak, Rinnai, and American Appliance). Hope you will one day "join" the mix.

Heatermon

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Henry_4

I am in the midwest

as well. Yes, FA is king, but I ask myself, why? I know that AC is essential, but I have watched my market develop, and the competitive price of FA is not everything. Now, I believe that a company like Carrier is trying to make a difference by using modulating fans and high eff. equipment, they and anybody else who look for a better way are to be commended. But, Carrier (et al) also make good airhandlers. The point, with FA, you get.....I see that hand....that's right hot air. Even if I use a low cost boiler, I can tie it into the fan coil and whamo...forced air made with water. Water holds so much more heat than air (3500x) that it quickly starts saving money. You can also run warmer air than you can with any gas furnace. Add in the ability to reset the heat and now you are talking bigger savings and more comfort.
A friend of mine in the industry, a big proponent of RFH always says, Henry, I used to use the radiant to sell the boiler, now I use the boiler to sell the radiant. The flexibility provided by the boiler lands him many projects. He can do RFH in the basement and the garage, FA upstairs with floor tempering in areas like the kitchen, towel bars in the bath, and don't forget all of the DHW from a quality indirect.
Yes, the systems as a whole cost more than a furnance and a water heater, but let's break it down.
Typical 3500 sq ft house plus basement in the Midwest:
[2] Furnaces..........100 k ea
[1] water htr......... 75 k
[1] garage heater..... 30 k
[1] Water htr, radiant 40 K
[1] Pool heater.......200 K
Total btu's...........545 K

A boiler package will do all of that in a fraction of the Btu input. Take out the pool, and the boiler still offers zoning and system flexibility that is greater than the sum of all the parts. Plus, if I want to add summer load later, great, I am not heating the house Memorial to Labor (summer in the Midwest) so I have the heat waiting to be used. If I use a 53 gal. indirect, I can almost triple the continuous output of a typical 40 gal domestic. Flexibility.
I call this stair stepping. An 80% furnace and domestic tank versus a full blown rfh and Viessmann, my price is not even in the same area code. But a Viessmann with a vitotronic control package doing the things mentioned above, now the price is getting closer, but more importantly, I have closed the gap and brought that boiler system into the range of a bigger percentage of the population. I am never gong to get everybody, but it will not be for lack of trying.
As always, I preach to the choir, but food for thought none the less. I remain grateful for the thoughts.

Henry

hot_rod

Well done, Henry

you bring up very good points, hard to agree

Keep in mind after having been in this business since.... well a long time. Started threading and soldering in the 80's. Not trying to sound like you dad, or anything

Now if I had a dollar for every time I heard that exact story! Although post is one of the most eloquently composed

Inevitabely a few years down the road that rep goes to work for a different "brand" Guess how the story goes then! Generally you hear nothing but negative stories about the former "best ever product"

I have nothing against your current brand, and few would deny they are near the top of the heap. Keep in mind they didn't "invent" hydronic heating, the concepts of thermodynamics, stainless steel, or even condensing technology. Certainly they have watched and waited in the background and presented a very nice product with the Vitoden. Is it the best? Is it worth the price? Does it heat water that much better than all the rest? For some the answer is yes. Others will not see the added value and cost. I have yet to find a contractor that offers ONLY your brand. Seems they all have a brand B they keep in the background

Marketing, desire, and the budget to do so is a big part of the manufactures game. Would you agree?

Keep up the good work, you put a fresh spin on things. That's refreshing!

hot rod

Mike T., Swampeast MO

Preaching to the Choir

Among the many reasons that forced air continues to dominate in the US is its perceived simplicity. The customer sees a "box," a flue and some huge sheet metal ducts that are just "certain" to be able to hold lots of heated/cooled air. After some growing pains and rather spectacular initial failures the consumer sees 95+% efficiency, increased reliability and thinks, "great." They're even willing Guinea pigs for such things as two (or more) speed blowers/burners. (I won't repeat here what my friendly heat man calls these by the way.)

The vast majority have lived with forced air the major part of their life, and while they might not find it perfect it seems to get the job done quite reliably with nothing more to adjust than the thermostat and little more maintenance than a filter they're always waiting too long to replace. They know that if the humidifier or electronic cleaner quits working, they'll still have air.

The quick delivery of these systems fits perfectly with the, "I want it and I want it NOW" attitude that WAY too many Americans seem to hold. Even in a small town, they can thumb through the Yellow Pages and find any number of firms to repair their system.

They see hydronics as an antiquated technology and it conjures images of massive ugly radiators or ticking baseboards that tend to stink when something falls in them or even quit working when new carpet is installed. Most won't even know if a hydronic system works with liquid or steam--particularly an old one. Even with the simplest of old systems they see valves, tanks, gauges and other strange devices. Anyone who ever tried to "quick chill" a soda in the freezer and forgot knows what happens when water freezes in a confined space. Anyone who has ever read "The Shining" may well think they have a monster in the basement just waiting to explode. If they've ever lived in a big steam-heated apartment building or recall "school days" they'll remember awful discomfort, hissing, spitting, banging, windows open in the dead of winter, stifling heat when its "not quite cold" outside, etc. They may well remember the "best" thing as being the neat way they melted crayons.

If they travel to Europe they'll certainly see plenty of radiators in all forms but often find they can't even turn up the heat to their comfort level (not realizing that it is a thermostatic valve that has been INTENTIONALLY limited).

Those who do their homework into the "modern" world of American hydronics may well get scared. As panel radiant has seen a lot of interest and makes some amazing promises they may well fall victim to "simple pre-designed all-in-one systems" mistakingly thinking that modern design has removed all of the "art".

They see a plethora of design choices sufficient to boggle the mind--even the minds of the pros. They read of horrid, unbelievably expensive failures--not only because of poor system design but the use of untested and/or inappropriate material and/or boilers.

When they see the PRO responses to a topic like "Would YOU buy a radiant house?" recently posed here, it's enough to make ANYONE think twice.

They see huge "boards" of stunning beauty (to a wethead at least). While certain to dazzle them and their friends, it's hard to completely shake the idea that, "it looks AWFULLY complicated with MANY devices of somewhat mysterious function."

The poor American boiler manufacturers are stuck in the middle of a seemingly endless swamp. Not only is there little residential market share in this country (with little or no chance of substantial export) but they have to try to design boilers for systems of ALL natures. High temp, low temp, fluctuating temp, high mass, low mass, mid mass, iron, steel, copper, plastic, hybrid (hydro-air) often COMBINED into the same systems!

Design, engineering, testing and production are ALL expensive propositions. Our government is of VERY little help in this regard as the vast majority of their R&D dollars go to the military and NASA where it takes decades for them to even release good rechargable batteries to the industry.

Investors, like consumers, want results--NOW! Even if they have been wary with their investment dollars they find that the crazy interconnected morass of investment allows EVERYTHING to tumble when just a "high-risk" bubble bursts.

American industry sees little or no need to spend the dollars to produce efficient use of fuel. After all, the US automobile industry has achieved a remarkable comeback by doing just the opposite. They nearly DIED in the 1970s until FORCED by the government to produce smaller, more efficient and SAFER cars. Now, by playing on base emotions (and finding a loophole in fleet average fuel economy requirements) they are making a quick killing.

[Funny that Ford is scheduled to close two Explorer plants near me--St. Louis and Louisville, KY. This despite record sales. Do they know something coming down the line, or do they just plan to export more of our manufacturing abroad? Forgive my cynicism, but are they just milking the public and playing them for chumps as long as possible? It certainly wouldn't the the FIRST time a large industry has done this to the people it supposedly "serves".]

European manufacturers like Viessmann and Danfoss have BIG market share--they have LOTS of money to devote to R&D and I believe their governments help them out as well. Their investors are not so interested in immediate stratospheric profits as reliable secure moderate income.

Instead of designing things that look more and more complicated on the outside, they "package" boilers and make neat "boxes" filled with control valves and such. They use time-proven, reliable, comfortable and EFFICIENT devices like TRVs instead of a myriad of zone valves, circulators, mixers, etc.

In this crazy world of uncertaintity the US seems destined to become more isolated, distrusted (even hated) than ever before. What remains of our heavy industry is likely more concerned with retooling for war use than developing any new consumer products. Any REAL reductions in our fuel consumption are more likely to be driven by government-mandated rationing than consumer desire anyway.

Maybe they'll dig out the REALLY old molds and start making solid fuel boilers again and I'll find out if my system still works with gravity and resurrect the coal bin!

Steamhead

Hopeful Sign

I have a neighbor who lives in a late-1940s Cape Cod house with scorched-air. The recently installed super-efficient furnasty was a selling point, but they are never comfortable.

Next door is an older house with a well-operating steam system. Guess where they spend as much time as they can?

I'm going over there this weekend to do a heat-loss and design a system that will keep them comfortable.

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Henry_4

are you insinuating

that reps are mercenary....GASP

I realize that this is not Kierkegaardian boilers in the eternal, but give me a little credit. I can objectively stand back and weigh the options. Your point is well taken, and reps have themselves to thank for the reputation. But this begs the question, is there a best boiler? I say yes there is, but it is not necessarily the same boiler in each applications.

One other consideration, the V does more than offer boilers, V offers an entire system, boiler, control, reset, valve, actuator, tanks, etc. we have been down this road. It is not a big stretch to say that if I did not have V, I would wish that I did, regardless of what I said.

Indiana just had the PHCC trade show today, it would take two hands to name the companies that let me know why they would be a good fit for Viessmann. Sure V is marketed well, but put up or shut up, V did not get there because they suck. At the same time, I can promote market and spend millions of dollars on horse manure, if you believe the hype and buy, you still have well marketed horse manure.

My point, anyone can say that they are the best, proof is in the pudding. I go back to what I said earlier, you make up your mind based upon what works for you. I am always going to be trying to change the mind of those playing with other toys....it behooves me to do so.

In the words of somebody smarter than me, Knowledge not shared is energy wasted.
Henry

Ray M_2

Tools

People are cheap.Here in the northeast there many older boilers and "newer FA" systems.Trying to sell new HI-TECH systems is hard.I agree that a good contractor can make any new boiler work better than systems installed 30 years ago.I use outdoor reset on every job,it might not be the best in the industry but it works.People are also not willing to break old habits,re: pumping away.I still see new jobs with the pumps on the returns.Does it work? Yes.People dont understand,"my FA furnace is 2 years old and we had no heat friday night,the service man charged me $275.00 dollars for a new ignitor.Do they cost that much?"I guess after all this what i am trying to say is let the buyer beware i know what i would put in my house.


Ray M

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Mike T., Swampeast MO

Kinda bet

that the company and surroundings have something to do with it as well. <:)

Don't know what your neighbors plan on doing but do know that most Capes are a bit tight space-wise. Do seem to recall many as having generous windows kind of high on the wall so there might be space for some panels.

Does it have the common small hall with open staircase? That might be part of the current problem.

Steve Minnich_1

Well said Henry

You are a very well-spoken individual and obviously quite intelligent. I look forward to the day when I am working with you. First, I believe I need to get my passport papers in order.:) Good job.

Steve

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Henry_4

Fortunantly for you

that is only funny to a few people. Well work it out and you can go in May.
Henry

MURPH'

TELL ME AGAIN.........

HOW THESE overseas boilers defy the laws of physics in being able to heat water better and more efficiant than anything out there. Is it the foreign engineering, the foreign metals, It "cost more" so it must be better.


"Sure V is marketed well, but put up or shut up, V did not get there because they suck." Where are the numbers?? the proof of the pudding. Realize now that you are confusing facts and opinions till there is documented testing. Opinions that are of course slanted because you are making a living selling these units. (MAYBE)


Seems to me your post goes full circle around your opinions and marketing savvy as to try to beat around the very issues you are promoting while at the same time insulting everyone,(in a suttle way) that does not share your "BIASED" opinion. But to read these slanted post of your preffered products kinda lend proof to the fact that you cannot justify why it is a better performer, it just is.(trust me)HAHAHHAHAHHAHAHHAHHA!!


great writing !!If not convincing at least very entertaining ,and I thank you for that..


Murph' (SOS)

Steve Minnich_1

The Able boys

are getting a complete refund on airfare and they told me to bring a stamped birth certificate, as I did. I've never traveled outside the US of A, they could have been more explicit in the info conveyed to me. Nobody was more disappointed than me. If they have a problem, they have my number.

MO

Steve

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Henry_4

I am not sure

if that was a right hand slap, or a left hand compliment.
I did not think that I would ever get your attention, must be my day.

Since we are on the subject, I would like to respond with how R&D translates into marketing. First, how does a exact and unvariated .8 mm gap between each pass of the Innox hex of the Vitodens effect condensing and performance?

How does flow rate in the Innox heat exchanger work with the decoupler to supplement system flow characteristics?

Why does the Vitogas 100, an atmospheric boiler, utilize a virtually sealed combustion chamber?

How does the shape of the Wohrgas burner and the butterfly flame pattern reduce NOx?

Why does Viessmann epoxy coat the sections on all cast iron boilers?

Why do we use a return injection tube in our boilers and what does that do to performance?

What is the benefit of keeping CO2 in a condensing boiler at 10.2%?

What are the pros and cons of wrapping four inches of insulation around a sectional boiler and how does that not help us in the AFUE test?

Who on earth had the idea to turn a pasta strainer upside down and fire gas through it (a gross over simplification)?

How can the Vitodens, in a single pass, drop the combustion chamber temperature from 1752F to 113F and the flue gas only travel two inches?

How does a simple air gap between dissimilar metals effect the rate of transfer and keep the VB2 from condensing or shocking, even with temperatures returning at 50F?

Why hope to achieve continuous delivery in a residential heating system and instead of varing time, vary temperature as the primary means of controlling room comfort levels?

My point, all of these things took money to figure out. Anyone can utilize these concepts, they cost money. R&D is expensive, maybe, just maybe, some of those costs are carried in the costs of our equipment. V also provides utillity in getting the equipment from point A to your building or job. Last time I checked, nobody that I work with in Chicago has to hop a flight to Frankfurt to pick one of these babies up.

It took me a long time to learn the answers to these questions, this is just a basic list. Murph, even if you never install a Viessmann boiler as long as you breathe, if you can understand these concepts, it will make any system that you do better.

As I said earlier, knowledge not shared is energy wasted, well maybe I am trying to strengthen you. Is this a waste of time, I do not think so, you are smart, you are capable and so are the billions of people that read these posts (see Dan, billions, Viessmann taught me to count ril good too!). And maybe, just maybe 25 or 300 people that never considered Viessmann are now thinking, "Hey, I never thought about that before, I am so glad that Murph brought these points to the forefront of my mind, thanks Murph."

So, Murph, thanks for bringing out the best in all of us, you sir are the reason that I love to do what I do. You sir are why the hydronics market will move forward. Why? You do not trust a word I say.

In the words of Ronald Reagan (Ronaldus Magnus, Ronaldus Maximus, Ron the Great, the Great Communicator) trust but verify. Sit through a Viessmann training class, ask these questions and see if it is worth anything to you at all.

Until then, opinions are like ***holes, every has one has one and they all stink. In the words of Officer J. Friday, "Only the facts ma'am".

Your buddy in the industry,
Henry

MURPH'

What a commercial........

But no answers to the questions, maybe they were skipped over for marketing purposes. Seems to me (I could be mistaken)That there really is not an answer to the question posed "what savings are realized by these units that justify all the extra investments involved?" We all know that AFUE ratings are not real life representation. So tell me about thermal efficiancies and where you get your numbers from and how the test are conducted.



And since we now have politics involved, Can you tell me what percentage of the R&D is offset by government supplements? Sure R&D is expensive, is it mandated by the government and subsidized?? Is this the same as the windmill theory to where it cost more to make the windings than any savings these units will ever produce?? What is the ROI from these units??


I see alot of cliche's thrown about, and tuff questions that only someone spending alot of time in the fatherland would be able to answer. But I guess it is a waste of time trying to find out (oops sorry wasted energy)what the real differences in fact are!!



Murph' (SOS)
(for your veiwing pleasure
tune in to the vieSSmann channel!!)

Henry_4

I once heard someone ask

Gary Fries of Wirsbo, how much is a radiant system? He replied, "How much is a bag of groceries?"
Reply: it depends on what is in the bag, I have to answer the same way.

The Vitodens has a published combustion eff, of 95%; however, that is at a set return temp. She is always changing temp as the outdoor temp. changes. At the same time, as return temperatures vary and the amount of flame input varies, thermal eff. is also changing. Thermal eff. is always over 90%.

Now here is the real benefit, as the Vitodens is changing output, I can have three way mix valves with actuators tied into the V control package that will modulate on reset also. So now, I have three distinct temperatures, all modulating off of their own reset curves continuously. When domestic calls, the Vitodens changes accordingly. If external demand (snow, spa, etc) calls, again the V control takes over and directs the correct temperatures.

All the parts and pieces may cost more as a sum total, but they are also worth more than the sum of their parts. If a V system and another system are both doing exactly the same thing, and both systems have a failure, my system will tell you what is wrong, all the parts are connected. How much is head ache relief worth? V has just removed a large chunk of the sytem hybridization and multiple phone numbers of different components matched up on a job for equal operation. Some guys find that very valuable.

Any of the Viessmann boilers share the same control philosophy. The Vitogas 100 has a published eff, of 86%. But, I also know, and this has been tossed about before, for every three degrees I drop my average system temp, I reduce my fuel usage by one percent.

Anyone that says proof is in the pudding is right. Brenneco, Lafayette, IN, put in three VB-2 boilers in their new facility. Last year in January, 10000 sq ft, fuel bill of 1600. This year, same month, 35000 sq ft, fuel bill 700. Yes, they had forced air, they now have radiant, but the average temp in the steel / cast iron Biferral is around 95F. So everytime the biferral fires, it is using 84% of the fuel. By dropping temperature out of the boiler, they are reducing the amount that they burn at 84%. So, which efficiency am I talking about? System efficiency, the only one that really matters.

Murph, I have never been to a single one of your installations, but if you did not know what you were talking about, someone would have figured it out long before now. You may have already decided that Viessmann is never going to be your bag, that is fine, we can agree to disagree. Fact is, Viessmann brings some powerful abilities and performance characteristics to the table. In order for you to do with another system, what V can do out of the box, you will increase your system investment. John Rushkin, famous British economist form the 1800's demonstrated that for us.

I would love for you to be as dogged an apologeticist for Viessmann as you are for anything that you already believe in. Fortunantly, we do not live in a Hegelian society and you are free to choose what you will. Thank you Lord for my freedom. But, I have not made any of this stuff up, it is not opinion, I can't just say, "trust me". Come to Viessmann, give us one business day and then determin if it walks or stinks. From that day forward, you will understand more about the systems that you install, even if you never install a Viessmann system.

On the words of Forrest Gump, "Stupid is as stupid does", sometimes a more correct statement is "Smart is as smart perceives".

Your buddy in the industry, Henry

MURPH'

Now that we have.......

All had lessons in philosophy of religion. Now what we need to address for all the good folks that frequent "The Wall". Do I need to quote P.T.Barnum here??


How many pleadings do I myself have to do to get you folks to please explain to me HOW you measure your thermal efficiencies, or now the new PC term "system efficiencies". we would like to know step by step by which measures you use to attain these claims. Or are these just calculated numbers ,and if so can you explain your method of calculating these, or again are we to just take your word for it?? Seems to me that to obtain stoichiometric combustion we are not talking 1752*,and exhaust temps of 100* by your own admissions.



Now tell us how after the combustion we cannot obtain 90% with (legitimatley) that you can get a full 90% thermal efficiencies all the time (or better)?? Does the combustion chamber increase and decrease with the flame?? that would be neat to see!! I think the flow of water past the chamber has a great effect on it, but does not lend proof to your claim of 90%.


Tell us by what means you measure these claims of thermal efficiencies, your comparison of apples to grapes don't cut it, all I hear is rhetoric and cliches. your writing is prolific and entertaining, but falls short of getting to the answer of my first question "how do these defy the laws of physics?" or do we re-write the laws as we see needed?? Besides that whorgas spaghetti burner kinda resembles a simple mantle used in gas lanterns.


Murph'

Henry_4

If we all must know

my philosophy of religion is also my worldview, ex nihilo, nihilo fit, it is the philosophical basis of the Christian world view. If anyone really wants to know what I am talking about, start a new post.

First efficiency:
I think we need to define our terms. As I undertand it, we have combustion efficiency and then we have thermal efficiency. The NASA web site defines these both precisely. Combustion efficiency is a measure of total fuel input versus total heat output. We use either btu's or watts to define. In a condensing boiler, as return water tempertaures decrease, condensate increases. Theoretically, the max combustion eff. one can achieve is 88%. From 88 on, we measure condensate (latent heat) and add it to the sensible heat.

Thermal efficiency is a measurement of heat in the combustion chamber versus heat in the medium flowing through the heat exchanger. One must take into consideration all boiler losses to determin.

Stoich. combustion ascribes to the following chemistry:
sensible: C + 02 = CO2 + heat
latent: 2 H2 + 02 = 2 H20 + heat
Viessmann seeks to minimize excess air, keep the CO2 in the system at 10.2% and the dew point of gas at 135F. Of course there is still some incomplete combustion here, hence, it is not perfect, but it is close.

As far as the heat exchanger growing, that is not possible, but we (as do others) modulate flame, theoretically, I could put a candle in a heat exchanger, combustion eff. would not be perfect because candles are inefficient, but thermal eff. would be very high since the heat exchanger with the cooler water temp behind it would readily absorb the heat.

Introduce a burner and modulate input for the same results. On a traditional vent system (such as on the Vertomat commercial series), 30% input is as low an input as one wants to keep the flue gas from collapsing. By collapse I mean not having enough energy in the flue to lift poisons out of the building. So obviously, the lower the input, the greater the thermal eff.

Next step, inorder to maintain stoich combustion, as we decrease fuel input, we must also decrease air input or CO2 will go wildcat and the dew point of gas will significantly drop. However, in doing so, unless I am very careful, and here is where more costly R&D comes in, my NOx will go through the roof if I do not "process" my flame correctly. It does me no good at all to sacrifice combustion eff. for thermal eff., I would be robbing Peter to pay Paul so to speak.

One other note, the wohrgas burner is not the matrix (spaghetti) burner. Both are designed to reduce NOx, which they do very well, but the Wohrgas is on the atmospheric 100 series and the Matrix is on the wall mounted 200 series.

Back to what we say and redefining physics. There are some very defined limitations on the Vitodens 200, the limitations are listed in the manual. If you customer has a system that is never going to operate below a supply of 160+ or is a continuous demand of 180, this is not your boiler because it will never condense and one wil have wasted the money to purchase such an appliance.

Just so happens, I have other equipment that will work fine in those situations (right tool - right job). How does the Vitodens stack up with other wall mounts? It does have higher combustion efficiency, I have opened up some different models and the Vitodens is easier to service (I know that comment was subjective, but you will just have to "trust me":)) but one would need to open both and determin for themselves.

All of the new breed of wall mounts are being listed at high eff. It behooves us to ask under what conditions. I have tried to lay out some of the conditions here. I know that this is wanting, but for lack of a class room setting, it suffices nicely. Again, I ask anyone to come to a V seminar and sit through the technical discussion. This is not a simple yes / no question. It is also not a game.

The late S.J. Gould would have us believe that operational science,in our discussion Thermal D and combustion, is led as much by philosophy and presupposition as it is by data and observation. However, in combusition, there are defined parameters, in wall mounted boilers there are defined parameters regardless of what I believe or want you to believe, the facts speak for themselves, I just present the results. I do not understand all of the parameters of combustion, but Viessmann is methodically going about the production of boiler systems that do the job very well.

We should all hope to understand the functionality of our tools as well as we possibly can.

Your buddy in the industry, Henry

Henry_4

I must know

does anyone care about this esoteric discussion between myself and Murph, whom I am beginning to appreciate very much, or is this just a conversation that two boiler wonks should be having at Dan's Bar and Grill on a Tuesday night?

Henry

Earthfire

listening

I'm reading.I think Murph makes a good point that the cost of "high efficiency" is not returnable in life cycle cost. Example in the 50's fuel injection was a idea for the moneyed class( mercedes,vette & some specialty toys) in 1966 my dads new Galaxie 500 with 289 2bl engine got about 20 mi/gal after I tuned it & cost about $2,500. My 2002 Crown Victoria costs more then ten times that, has fuel injection and DOES NOT get 18MPG & I can't tune it. My 76 F350 has power brakes and never cost me more the $200 +/- change for a brake job and the brakes go about 40,00 mi., My 2000 E 350 has ABS . The brakes don't last longer then about 18,00 mi. and it cost me between $1,200 to $1,300 each time for a brake job. And the '76 stops better with a load on.And by the way that 360 CI 4bl. gets about 2.5 mpg better then the injected 5.9L. Modern technology has shown no value to me in those two examples.I agree the technology of V's products is impressive . But how many are still going to be hanging on the wall in 20 years with the traditional maintinance schedules that the typical homeowner observes. And that washing machine that they installed next to it ,even with outside combustion air makes me wonder about its survivability over the long term. Is the unit a viable piece of equipment? It Depends.Is it worth the investment? It Depends.Is the corrosive condensate something the EPA and local sewer districts will start regulating? who knows! I'd bet yes, sooner then later. The education shall continue.

Henry_4

Great points

that being said, maybe we all use cast iron and forget about anything else. However, Vi does have condensing Vertomats (commercical series) that have been in operation since the early seventies. The Vitodens, although a different burner and configuration uses the same materials.

As far as payback, I can utilize ASHRAE bin data, determin the amount of time I will be at what temp level, compare it to my reset schedule and get an energy analysis versus a static output boiler. Generally, the payback is good, more so on commercial projects where loads are higher, but still present at any level.

I just did a project for a county garage. The Vitodens versus a low mass fin boiler. All said and done, we were looking at a yearly savings of just under $500 per year. payback was six years. However, the contractor has utilized Viessmann for many years, understands ease of serviceability on our equuipment and the client was concerned about enviromental impact. More than just fuel use, while important, was considered. Plus they are going to be in the garage for then next 30 years, so it made sense.

Now, if the Vitodens craps out in three, big problem. But that unit has been in use since the early 90's, and shows no signs of limited life span.

As to maintenance, that is true on any equipment, not just high efficiency.

Great points,
Henry

Walt Risler

I have been reading this post for the last couple days and I wanted to write these comments. We bid on a large Midwest commercial project a few months ago and we were the successful low bidder. The specifications listed Viessman and AERCO as the two acceptable boiler manufacturers. This job had three 2M BTU boilers for the base bid. After a lot of searching, we had quotes from Viessmann and AERCO. I cannot remember exactly right now but Viesmann was around $123,000 and AERCO came in around $78,000. The Viesmann reps said that they cannot successfully bid against AERCO, but on the other hand, no one from Viessmann contacted me about possibly presenting to the owners that if we used Viesmann what the added savings might be. We did not get any follow-up calls either. I checked out the Viesmann units at the Toronto trade show last October and the ASHRAE show in Chicago last month and I was impressed with the equipment but on plan and spec jobs it will be hard for Viessmann to compete unless they get the price down, in my opinion, or, the sales reps need to show the design Engineers that Viesmann should be bid as an alternate, to show the owners that the higher costs for their units are worth the cost in energy and maintenance saving over the life of the equipment.