high effency boilers

S Ebels

Three main designs that I'm aware of, but I'll be the first to say that I don't know it all.

One of the basic designs is the stainless steel HX models used by Munchkin, Knight, Trinity and others. All these use a HX manufactured By a (French?) company called Gianonni (sic) From what I know, the HX is designed in such a way that about half of it is actually condensing. Some of these are step fired and some are modulating. The HX is fairly light gauge stainless steel and some companies use silicone caulk to secure the tubes to the headers while others weld them. Control sophistication varies by manufacturer.

The next type or genre' is the aluminum block group. Buderus, Weil McLain, Dunkirk to name a few all use a heat exchanger cast from aluminum. Controls again vary by manufacturer with some being proprietary and some being outsourced.

There are no Mod/Con boilers on the market that even remotely resemble the Viessmann Vitodens 200 in construction. The HX is 316Ti stainless steel and is one piece. Think of a tube with a rectangular cross-section about 3/4" x 2" and 25-35' long. Now roll this straight tube into a coil about 12" in diameter and place the sweetest burner I've ever seen in the middle of it. Form it in such a way that a uniform .8mm gap exists between each coil and you have your basic Vitodens HX/burner module.

With this design the entire HX is capable of condensing and the airflow through the coils makes it basically self cleaning. This design also keeps condensate problems to a minimum. I haven't seen another M/C boiler that I think will run as long as the Viessmann.

PS: Make that four types. Some, like the Monitor Products MZ use a finned tube design HX. The MZ has a long and proven track record of reliability.

I'm sure I have left some out and I'm sure I have trampled a few toes. I would dare say though that no one here would dispute that the Viessmann is alone at the top as far as features, build quality and design. I like 'em a lot and the company is the greatest to work with of any I know.

Andy_17

High Effiency

I just renovated my home & need to install a larger natural gas boiler. System is 1/2 floor radiant & 1/2 forced hot air, on seperate floors.
Would love to take advantage of the higher effiency boilers out there. from some basic research Veissman seem to be the top of the line w/ Knight, Buderus following up. Is there any advantage of one over the other as far as quality,reliability, longevity, etc. w/ this type of heating system am I looking @ the right type of equipment?

tom_49

modulating/condensing is the ONLY way to go. It will save you $$ forever.I think your on the right track.

Look around here, you'll find lots of discussions on these. All brands.

Do a heat loss. Get a good contractor, Dont skimp,gas aint gettin cheaper.

Good luck Tom

ALH_4

It depends

It depends on what you want. Most of the condensing boilers on the market are just fine. Viessmann's boilers are a notch above the rest. If you want the best, buy Viessmann.

-Andrew

joeoilman

the knight is a good choice. also the new dunkirk q-95m is out too. it's the new modulating one. real nice.

John@Reliable_10

Andy, something to think about..................

while I agree that fully mod/boiler is the way to go,most only have a 10 to 15 year warrenty.The days of 30+ year boilers are gone.With that said the Knight will give you the biggest bang in it's life time compared to others I feel,as they all are around the same efficiency but different in up front costs.Also it's best for you and equipment installed to find the right contractor.

Supply House Rick

What makes Viessmann better?

Besides the price? This is a serious question. What more can you achieve besides efficiency? Isn't that what it's all about? Please explain. Explain the extra money so the common man can understand. Rob

ALH_4

Differences

What makes Viessmann better is the extra quality in the construction. Look at a competitor's stainless steel heat exchanger and then look at a Vitodens coil. The difference is amazing. There is not a lot of "good enough" in Viessmann's current lineup. The Vitodens 100 and the EC series boilers are their biggest compromises, and those are still very nice boilers by comparison.

I'm not saying other boiler manufacturers do not build very good boilers. You probably will not save a lot of fuel by using a Vitodens instead of another condensing boiler. The difference is in quality of construction, versatility of the controls, and engineering backing up the design.

-Andrew

S Ebels

Viessmann

Viessmann is all about life cycle costs. They look at and design their products from the perspective that says, "How can we make this boiler last the longest, pollute the least, have the fewest repairs all while providing top notch efficiency". The initial price enters into the equation only to the point that it affects the final, total cost of operation when the product has reached the end of its life.

In other words, like this (way over simplified)

Boiler A costs $4,000

lifetime repair and maintenance costs are $5,000

Lifetime fuel costs are $14,000

Lifetime electrical operating costs $1,200

Installation costs are $2,800

For a total of $27,000

Boiler A lasts for 10 years



Now the Viessmann way

Boiler V costs $7,000

Lifetime repair and maintenance costs $4,000

Lifetime fuel costs are $13,500

Lifetime electrical costs are $900

Installation costs are $2,200

For a total of $27,600

Boiler V lasts for 14 years while producing less than half of the pollution that boiler A does.

Which boiler is "cheaper" to buy?

Again, this is drastically oversimplified but shows the design philiosphy that I have found to be true in all Viessmann products I have ever used.

Andy_17

high effiency boilers

It seems I've found some Veissman fans. Thanks for all the great Info, I really learned alot. I'll be meeting 2 heating contractors later this week, Hopefully they are both as knowlegable about the products & installs as those who post here.
Thanks again!

S Ebels

Andy

I have held in my hand cross-sectional pieces of the Vitodens HX and the Gianonni HX. They don't even look like they come from the same type of product. I have pictures of them somewhere but can't find 'em to post them here. Probably get a bunch of folks mad at me if I did. The Viessmann "tube" has about 3 times the material in it and it's higher grade stainless to boot.

I'm not saying that anything but a Viessmann is junk and won't do its job, just that there is Viessmann and then there is everything else. They just think differently than any other company I have run into in the heating industry.

Darin Cook_2

Triangle Tube

TT Prestige will give you alot of bang for the buck! The heat exchanger is made from 439 SS which is a few steps down from titanium. It is a firetube design rather than a watertube design. This greatly decreases the pressure drop through the boiler allowing the use of smaller and less expensive circulators. It has a great self cleaning design. Which will maintain your efficiency levels. SS heat exchangers help neutralize the ph from the exhaust which is why you will not see a condensate trap on the exhaust venting of a SS boiler. Outdoor reset is included with the MCBA control package. The MCBA is capable of many,many control features. The boiler is sold at a great price which will greatly lessen the amount of time of the payback period. Combine that with a TT smart indirect ( limited lifetime warranty) and you have a very high efficiency package.


Darin

Ted_13

make that 4 types

The Hydrotherm KN boilers are modulating condensing boilers that have a cast iron heat exchanger. It's a down fired counter flow design that is fuel air coupled providing stable co2 throughout its range(it never burns dirty). At the moment they offer a 750 mbh, 1000 mbh and a 2000 mbh. 5:1 turn down. As far as the life expectancy ? I don't know, it is cast iron.

Supply House Rick

I agree with Darin

We sell 3 major boiler lines. The Prestige is now our top selling high efficiency gas boiler. Prestige passed the beloved GB142 in sales not to long ago. The have the PS110, PS175 & PS250 which covers most applications.

Please check out the design of the heat exchanger and the function of the control and you will be impressed. The way I look at is if Darin & Mark are installing it, there must be something to it. You have all seen their work...

Rick