Old system & Hi AFUE bad match?

Mike T., Swampeast MO

The higher AFUE-rated TRADITIONAL boilers [might] not be as long lasting with a standing iron system.

The highest AFUE-rated CONDENSING/MODULATING boilers however are a WONDERFUL match and your fuel use is highly likely to plummet while your comfort increases. They are more complex and really need an annual inspection/cleaning however.

Many in the trades are highly resistant to change as they prefer the tried-and-true and have been burnt by "breakthrough" products in the past. While some condensing/modulating boilers are nearly certain to be found more or less reliable than others ("typical" isn't even really known yet), the general quality level and field experiences reported here seem reasonable.

p.s. Direct comparison of the AFUE between traditional and condensing/modulating boilers is currently invalid. If rated on the current scale, condensing modulating boilers <I>in actual service</I> would be well over 100!

mjj_2

Old system & Hi AFUE bad match?

We have a ~80-yr-old house with a 40+-yr-old oil boiler and cast iron radiators. While discussing with an HVAC co. rep. replacement of the boiler with a new gas model,he steered me away from hi-efficiency gas models, saying that older heating systems work best with mid-efficiency boilers (have fewer service calls). Intuitively this seems to make sense, still I was hoping to take advantage of hi efficiency equipment. In general are old heating systems less compatible with hi efficiency gas boilers?

Steamhead (in transit)

Two questions

first, this is a hot-water system and not a steam system, right? If it's steam and they're trying to get you to convert it to hot water, kick them out of the house. This type of conversion can turn a perfectly good system into a nightmare of leaks.

Second, have you compared the cost per BTU of gas with that of oil? I'll bet you find that gas is significantly higher. If you get an oil-fired boiler now, you can put a gas burner in it later, but you can't switch a gas boiler to oil.

Constantin

Allow me to quibble...

... but not about the wisdom of trying to convert a steam system to hot water! I totally agree with you that such projects are likely candidates for "the leaker from heck" nightmares...

However, on the question of oil vs. gas prices, I don't think there is one-size-fits all response, as your post seems to suggest. From the limited reading I 've done here, the per-BTU prices of different fuels vary greatly by region.

For example, up here in Boston, oil has (traditionally) been about 40% less expensive per BTU than gas. These days, the prices are closer. On the other hand, I seem to remember a post from the midwest where the oil was significantly more per BTU than gas...

I also agree with you that an oil system offers better flexibility than a gas one. At least one can convert, if needed, to gas.

Bob W._3

Oil/Gas

I talked to someone today who couldn't lock in on his fuel oil(financial problems) and is paying close to $2.80/gallon!
Our gas is still about $1.00 therm, scheduled to go to about $1.31 this year, an all time high. It seems like the Northeast is the opposite of the Midwest. Propane is over $2.00 as well. Neither can compete with gas, yet anyway. Eventually we will all be switching to corn stoves to stay warm

Mark Hunt

Interesting


I LOVE when I go up against a company that tells a customer what your "heeter guy" told you.

The FACT is that you WILL see savings with the modulating/condensing boiler.

EVERY SINGLE customer that I have installed one of these systems for has seen a MINIMUM of a 34% drop in therms of gas consumed.

Find a contractor from the 21st century.

Mark H

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Constantin

Up here it aint that great either...

... I just paid $2.44 a gallon for oil, and gas is going to $1.71 a therm. That makes oil still cheaper than gas, but not by much. Had I locked in (and that's a whole other story), my #2 per gallon cost would have been $2.09.

Steamhead (in transit)

Have you guys

figured in the various fees, taxes etc. or are you just going by the gas companies' advertised price? When I compared prices in the Baltimore area in August, those fees and taxes pushed up the price of gas well beyond oil.

On my last bill, the bottom-line price for gas was $2.02 per therm, based on a residential account with a usage of 18 therms. In August it was $1.83 per therm. That's a bit more than a 10% increase in two months.

Bob W._3

Frank, we were paying $0.60 to $0.80 per therm just a few years ago. Gas had always been cheap in the Midwest until it spiked one winter about 5 years ago. Since then it has been steadily rising (the investors have to make money you know). We are paying about $1.00 per therm now +/-, including delivery charge. In the warm months the price is a little higher due to the$6.50 base residential charge. My bill for the month ending 9/6/2005, for 33 therms (@ .96486) was $40.83. I think you folks out East are paying high prices in part because part of your gas infrastructure is so new. As I understand it gas wasn't available in large parts of the NE U.S. until recently. Residential fuel oil has almost gone the way of the buffalo in these parts.

mjj_2

All three heating reps. who have seen our system (~2000 sq. ft. 2-story house, hot water heat and heat loss of 98,000 BTUH) have recommended one-stage gas boilers of 80-84% AFUE. (gas is still cheaper than oil in Toronto, although this is not the only consideration) Recommended brands include Carrier BW1/BW2 or BW3 or Lennox GWB8-IE / GWB8-E/S (two brands that may be made by the same manufacturer) and Smith( model yet to be quoted).

My point is that no one suggested a high-efficiency modulating, or even a multi-stage boiler. One rep reluctantly mentioned the SlantFin Trinity (~87% AFUE), the other stated that he carries Viessman, but does not recommended it, because of corrosion problems. None of them treat the boiler water. Are some multi-stage or modulating-condensing gas boilers & their heat X-changers more impervious to corrosion than others? HVAC professionals in Ontario and New York state is our water too acidic/ basic to allow for high AFUE boilers? Any suggestions would be appreciated

Constantin

That's a problem that is easily solved...

... two solutions come to mind: Call George at Rhomar Water Systems and send him a sample. He'll have a recommendation in no time. If you really want to play it safe, buy Georges cleaner, then fill the system with 55 gallon drums of distilled water and the conditioner. Alternatively, buy some less-than-acidic water from a local source. Can't be that expensive to fill an entire heating system.

Besides, I'd like to understand why a CI system should be inherently more resistant to boiler rot than something as thick or as high-quality as the 316Ti HX in the Vitodens. The only scenario I can foresee that metal being eroded is high-chlorine city water feeding the system ad nauseum due to a leak somewhere.

I'd call Viessmann in Canada and find a rep that has taken their training courses and knows what he/she is doing. Considering the potential savings, I'd investigate low-mass, condensing, modulating boilers further.

Chuckles_4

> All three heating reps. who have seen our system

> (~2000 sq. ft. 2-story house, hot water heat and

> heat loss of 98,000 BTUH) have recommended

> one-stage gas boilers of 80-84% AFUE... (


Regrettably, this business is full of "changeout artists". You can drop in a cheap boiler in place of the old one within a couple of hours, and make a healthy profit. Also customers usually care about the price most of all, and changeout artists respond to what customers want.

The people you have quotes from do not know about modern trends in boilers. They haven't had any need to know, they are making good money doing cheap changeouts. And indeed, maybe you won't save money by getting a better system. You'll get much more comfort (from outdoor reset) and a good feeling for helping conserve, but you may sell the house before you make money on the deal.

If you still want to get a high-efficiency system, you'll have to find someone who knows about them. I know from experience that this can take some work.

>HVAC professionals in Ontario and New York state is our

>water too acidic/ basic to allow for high AFUE boilers?



No, these contractors are feeding you nonsense. They don't know about modern systems but they know that customers know even less than they do, so they can make authoritative-sounding statements.

Mike T., Swampeast MO

Resistance to Change

Nothing new about contractors only recommending the materials and methods with which they are most familiar.

Particularly when it comes to a heating system with standing iron rads, they know that they can quickly drop in a traditional boiler with little chance of any callback and high expectancy for an extremely long life.

Beyond that, they don't have to bother with learning anything new...

Part of the reluctance is an understandable "wait and see" attitude. Contractors from all trades have likely been burned by the "great and new".

While condensing/modulating boilers are not yet a fully mature technology, there have been past failures from which to learn. High-efficiency furnaces have had similar problems and they are not fully mature technology either! One will get me 50 that these contractors have NO problem installing the newest and highest technology furnaces!

NOW is the time for hydronic heating contractors to study the new methods and install the highest efficiency boilers properly. There will be a learning curve and you [might] have some problems but you and your customers will benefit!