What is the most efficient residential gas fired steam boiler you guys have seen out there?

ST

I am plumbing/hvac contractor in NJ.  I am looking for the most efficient residential steam boiler.  Anything higher than 85% out there? 

Big Ed_4

My Choice

A properly sized Burnham MegaSteam boiler with a Riello gas burner .Vapor stat limit and a tight system ...

ST

Thank you!

I am a fan of the MegaSteam for oil, but have never ran a gas burner on it.  Sounds good!

Charlie from wmass

Smith or slantfin

I have not heard the Mega steam was approved for gas use yet. It should be good but without the blessing of Burnham I would not convert it to gas. I have heard of nothing in the United States with over 85% for steam when firing gas for residential use.

Steamhead

Charlie is right

the MegaSteam isn't approved for use with gas burners. Not sure why Burnham hasn't tapped the gas MegaSteam market yet. 



The Slant/Fin Intrepid and Smith 8 series steamers are approved for gas burners, and their thermal efficiency is better than any atmospheric steamer. I'd use one or the other of these.

Mark N

System Efficiency

I can understand wanting to be as efficient as possible but at what cost.  What is the premium one pays for the Smith or Slant-Fin with power gas burner above the cost of an atmospheric boiler?  Is it 25% more, 50 % more.  The reason I ask is I had a Burnham IN-4 installed 18 months ago.  I just received my latest bill from PSE&G my local New Jersey utility.  I decided to go over my bills for the last 6 six months back to October to see what my gas usage was.  My total usage was 744.2 therms over 184 days.  By my calculations I used 541.8 therms for heat over that time.  I'm not sure how much more efficient the boiler with power gas burner would be.  Say it was 5%, that equates to saving 27.09 therms over that period.  I pay $1.36 per therm so that comes to $36.84.  Not exactly a huge sum especially if the boiler with power burner is substantially more expensive.  Have you done any analysis on what the saving are versus the difference in cost.



Mark

Charlie from wmass

The cost is not much different.

the issue is usually noise of a power burner vs atmospheric and also that 1.36 is today what about ten years from now? I do install mostly atmospheric boilers on the residential level. The 5 % adds up faster in larger systems. this is why after a certain size it is all wet base power burners.

Big Ed_4

Boiler Cost

I always say buy the best and most efficient equipment you can endear ....



First point your buying a level of boiler anyway , Boiler+ installation parts + labor and miscellaneous . Up grading cost a % more and would give you either longevity higher efficiency or both ..



Over the cost of equipment it would pay for it self .. As prices of fuel rise ( fuel , delivery and taxes) , the return comes back sooner ...



Savings are a tax free investment return ...



I found as with my self , once you already spent the extra you are glad you did as the lower fuel bills keep coming ..



Combustion efficiency ratings are misleading because system loss is not calculated into your total savings .



Properly sizing a boiler which in most cases means buying a smaller boiler will cost less in the initial install too ..



Over time the better system is a better buy ...



People living in Europe are already conditioned to look for savings ,, They would ask" what is the best ?" , over here we ask "How much?"

Robert O'Brien

Steamhead

I had a prospective steam job for a Green Homes program. They wanted the AFUE rating for either the Intrepid or HB Smith with a power gas burner, unfortunately there isn't one!

Mark Eatherton

A.F.U.E. is not something you can hang your hat on....

It is nothing more than an approximation based on identical operating characteristics, which never really happens in real world terms.



For example, going from an 80 AFUE to a 95 AFUE, the math would tend to make one believe the annual savings to be only 15%, when in reality, people in the field are experiencing a minimum 30% savings.



AFUE was intended as a guide for the consumer for reasons of comparison, and it was established so that people comparing forced error systems could compare them against force hydronic systems, and even at that, there is no real "system" comparison.



Like another government standard, M.P.G., your milage may (probably will) vary...



In my opinion, the whole energy program needs a major make over.



ME

Steamhead

I'll have to see if I can find it

On oil the Smith is 85% when you use the lower of the two firing rates specified for each model. On gas only the lower rate is approved. The Intrepid is 83-84% on oil, but it's fired pretty aggressively, the same way the Smith is on oil at its higher firing rates. It would probably do better if down-fired a bit.



I'm really not sure how the use of a power gas burner affects the AFUE. I would think it wouldn't make that much difference, since you're still releasing the same number of BTUs into the firing zone.



Gordon and I consider the thermal efficiency (DOE BTUs out as a percentage of BTUs in) as well as AFUE when evaluating boilers. But if you're dealing with the typical micro-minded bureaucrats, that may not help much.

Robert O'Brien

I called

Slant/Fin,it's not an OEM setup with a power gas burner,they tell you it's OK but you are on your own.

Big Ed_4

Buderus

Buderus told me the same thing a year ago , its ok but your on your own , They also mentioned to me, bump up to the input from oil .



My bet the lawyers are dictating to the board of directors ...

ST

Thanks

Thanks for the information.  Thats pretty much what I thought, but there is always something new to learn out here.