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Re: Asbestos (paper type) behind recessed radiator - who can help?
Treat it as if it is ACM (asbestos containing material). Is that steam radiators? If so, the Abatement companies are capable of disconnecting a radiator. No biggie. Mad Dog 🐕Yes, steam radiators (recessed type, though). This is helpful, thanks - we have an asbestos company that two friends recommended, but I was not sure if they would do the radiator removal to be able to actually get at the asbestos paper.
Re: Steam boiler maintenance
Not recommended. That exposes the entire boiler block to air and corrosion. Some people fill their boiler up into the risers to keep the block completely under water. Others, just leave it alone. I personally change the water level up or down an inch or two at the end of the heating season so as to prevent rust through at the normal water line where air and water meet.
Fred
1
Re: Why my 85% efficient cast iron boiler is really only 78% efficient
Since you seem to like crunching numbers..
I think this BIN data can be useful for analyzing heating systems, performance, efficiency, etc.
Some bucket time needed to look into these efficiency numbers.
I suspect few boilers operate at steady state condition for much of their life. If so the math is simple.
Steady State= heat output in Btu/hr ÷ energy input of boiler
128,000 ÷ (1.18) ( 140,000 Btu/ gal #2)= 77% efficient
Cycle Efficiency= total heat output over period of time ÷ energy content of fuel used over that time. Obviously a lower % number
Run Fraction= burner on÷total elapsed time
5 minutes on ÷ 5 min + 20 min = 20%
Look at a partial load condition with 128K boiler supplying a 40K load
40,000 ÷ 128,000= 31%
Plot that 31% on this Brookhaven developed chart, at 30% efficiency goes south quickly.
If you know the actual heat load of the building you can go a step further
Heat load of 100,000 (70°-40°) ÷ 70°-0°= 20,000 BTU/hr - minus internal gains, call it 20,000
22, 860 ÷128,000 = 17.8%. on the graph, looks like you are slipping into the mid to low 70% range
Use your actual numbers. An unknown is which boiler output number to use IBR net assumes 15% heat loss. To tighten that number a piping heat loss could be used. In a system with large uninsulated piping, boiler in cold spaces that 15% number could be off by a bit?
Formulas from Modern Hydronic Heating & Cooling 4th edition Chapter 3
I think this BIN data can be useful for analyzing heating systems, performance, efficiency, etc.
Some bucket time needed to look into these efficiency numbers.
I suspect few boilers operate at steady state condition for much of their life. If so the math is simple.
Steady State= heat output in Btu/hr ÷ energy input of boiler
128,000 ÷ (1.18) ( 140,000 Btu/ gal #2)= 77% efficient
Cycle Efficiency= total heat output over period of time ÷ energy content of fuel used over that time. Obviously a lower % number
Run Fraction= burner on÷total elapsed time
5 minutes on ÷ 5 min + 20 min = 20%
Look at a partial load condition with 128K boiler supplying a 40K load
40,000 ÷ 128,000= 31%
Plot that 31% on this Brookhaven developed chart, at 30% efficiency goes south quickly.
If you know the actual heat load of the building you can go a step further
Heat load of 100,000 (70°-40°) ÷ 70°-0°= 20,000 BTU/hr - minus internal gains, call it 20,000
22, 860 ÷128,000 = 17.8%. on the graph, looks like you are slipping into the mid to low 70% range
Use your actual numbers. An unknown is which boiler output number to use IBR net assumes 15% heat loss. To tighten that number a piping heat loss could be used. In a system with large uninsulated piping, boiler in cold spaces that 15% number could be off by a bit?
Formulas from Modern Hydronic Heating & Cooling 4th edition Chapter 3
hot_rod
2
Re: What is this vent?
W.A. Russell Co. was also located in Bridgeport, CT for a while. They also sold vents with the "WARCO" name.
Re: San Francisco steam help
It looks like your steam pressure is set too high. Please take a close-up photo of the two gray boxes that say "pressuretrol" on top of the boiler. Those vents are supposed to operate at three psi or less.
bburd
1
Re: To those with more knowledge than myself, would you install a new gas or heating oil system ?
Some additional info. Compare fuel costs here.
https://coalpail.com/fuel-comparison-calculator-home-heating
The EIA website has fuel costs for various areas of the country with data going back 20 years or more to get past fuel cost trends.
https://coalpail.com/fuel-comparison-calculator-home-heating
The EIA website has fuel costs for various areas of the country with data going back 20 years or more to get past fuel cost trends.
hot_rod
1
Re: To those with more knowledge than myself, would you install a new gas or heating oil system ?
Hello all, first post….thank you for all the info provided here.https://www.maine.gov/energy/heating-fuel-prices
We are buying an old home in Maine, it presently has no heat system in the home and I’m looking at gas fired and heating oil systems, trying to determine which one to use. I’m thinking baseboard hot water on the exterior walls. Either system will need the fuel delivered by truck. The basement foundation is brand new, house is old and wall are stripped.
I’m interested in possibly the latest state of the art quality system that you would choose for yourself.
Thank you for any input or opinion
Propane is about 25% less per gallon but propane contains about 40% less energy per gallon.
Re: Why my 85% efficient cast iron boiler is really only 78% efficient
and unless the chimney is lined to take it -- stainless steel -- it will live a short and unhappy life. Replacing it will eat any savings you might make.
Re: Why my 85% efficient cast iron boiler is really only 78% efficient
To me you are incorrect in your assessment because when you are measuring your flue gas you are only measuring sensible heat, not latent heat. The process by which there is water vapor would mean that the heat energy required to create a water vapor is already absorbed, the latent heat of vaporization. so that heat has already lowered the flue gas temperature. That would be why you are not deducting the 7%. the products of flue gas that you read in the flue have already completed the process of combustion and latent heat of vaporization. You gain that 7% when you condense the flue gases in the secondary heat exchanger of a condensing boiler (7% is a number you are using so i will use that) .
So i totally disagree with your statement. That's is why anybody that has combustion analysts of boilers and furnace for 25 years like myself will tell you that i never see an actual 95-97% efficiency number because the combustion analyser cannot measure the latent heat, only sensible heat. And i have done well over 1000 test.
So i totally disagree with your statement. That's is why anybody that has combustion analysts of boilers and furnace for 25 years like myself will tell you that i never see an actual 95-97% efficiency number because the combustion analyser cannot measure the latent heat, only sensible heat. And i have done well over 1000 test.
pedmec
1
Re: Why my 85% efficient cast iron boiler is really only 78% efficient
You have also hit -- I suspect accidentally -- on why condensing furnaces running on gas can advertise high efficiencies -- they are capturing the latent heat in the water vapour, so if you are playing with the higher heating value all the time, the numbers work. This is also, however, one reason (there are others) why you don't see condensing furnaces on fuel oil: the amount of water vapour produced is much less, relatively speaking, and so the higher heating value isn't as different from the lower heating value, and there isn't much point in trying to capture it.