Mom's oil boiler went out, got questions

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Some gas company's will give really good incentives to activate an unused gas line. It would be worth calling the gas co in that area to see what they have to offer.
 
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Huh? Care to explain that again?!?
It's more fuel efficient. I don't think you'll find too many steam boilers that go higher than 82% AFUE whereas hot water boilers are over 96% AFUE. Basically you need to boil water over 212 degrees and it's also under pressure so I think it's about 240 degrees at 10PSI or something like that.
 

JHZR2

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It's more fuel efficient. I don't think you'll find too many steam boilers that go higher than 82% AFUE whereas hot water boilers are over 96% AFUE. Basically you need to boil water over 212 degrees and it's also under pressure so I think it's about 240 degrees at 10PSI or something like that.

I think that’s apples and oranges though.

Yes, my mod-con boiler achieves 96+% efficiency because it can tailor its actual temperature setpoint and is designed for the condensation that will occur. It is extracting all the energy it can.

But it’s affecting a huge mass of water and cast iron radiators.

A steam goes to a higher temperature to raise steam, sure, but the amount of working fluid mass is much lower. The thermal mass of radiators are the same, but at least the type of steam systems like in my parents’ other house, is only one pipe, so less losses and half the piping to heat up.

Totally agree if we’re talking mod/con vs steam boiler, at least until the point where one can’t take advantage of the outdoor reset and lower set point temperatures from the boiler.

But traditional hydronic vs steam systems are I think much closer.
 
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If you do have natural gas to the house most people will pick that. You can have a contractor do up a cost comparison. I have a few numbers in mind but they are in metric. One problem is that gas is up in price this fall so it might not look great momentarily. Check with your utility and see if they have some rebates to take the house off oil and be put into gas. 26 liters of oil = 27 m3 of gas as far as energy content goes. These are both equal to one giga joule. ( GJ). For the time being you can pick up some 1500 W heaters, but can only put one on each independent breaker. I recommend the oil filled heaters. You can always keep them around for extra heat or put them on E Bay after the new boiler is installed. It might be tricky to find a company to pump out and remove the fuel. Usually the oil company cannot take it back but there are probably companies who will remove it and sell it to country folks who have waste oil furnaces. Good luck.
 
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Steam boilers have a steady state efficiency of around 80 percent while making steam. Each time the boiler shuts off it must be reheated to above 212 degrees to make steam again hence the loss reheating the water. Some large building systems run under pressure meaning no downtime losses. Forced hot water systems operate under different temps depending on type of radiation. One hundred years ago coal fired steam boilers worked well because of the steady fire.that was fed and dampered according to needs.
 
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I replaced our oil fired steam boiler 4 years ago, with a gas steam boiler. Best thing I could have done. It developed a internal leak where I had to add water to it twice a day, just for it to keep making heat. The new boiler has just about paid for itself in saving. Oil prices went up at every delivery, the first year we had it we saved $1200. Average oil cost per year was between $1900-$2400. Luckily the oil tank was in our basement, and the company pumped out the last 60-70 gallons of oil and cut it up. In New Jersey you have to remove any oil tanks. If it's buried in the ground that can run you about $3500 if there are no signs of leakage, more if there's contaminated soil to be cleaned. Gas is cleaner, no oil smell in the basement, you can get by for a couple seasons without the need for service, and it has fewer moving parts to fail. Knowing what I know now, I would never go with oil again. We now can turn the thermostat up, and have a warmer house for alot less than what it would cost using oil.,,,
 
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I think that’s apples and oranges though.

Yes, my mod-con boiler achieves 96+% efficiency because it can tailor its actual temperature setpoint and is designed for the condensation that will occur. It is extracting all the energy it can.

But it’s affecting a huge mass of water and cast iron radiators.

A steam goes to a higher temperature to raise steam, sure, but the amount of working fluid mass is much lower. The thermal mass of radiators are the same, but at least the type of steam systems like in my parents’ other house, is only one pipe, so less losses and half the piping to heat up.

Totally agree if we’re talking mod/con vs steam boiler, at least until the point where one can’t take advantage of the outdoor reset and lower set point temperatures from the boiler.

But traditional hydronic vs steam systems are I think much closer.
Go and take a look at the steam boilers you can buy. I think because of the nature of steam, I haven't seen one much about 82% let alone 90%. I still have a few steam boilers, they're about 70-120k BTUs, you might get higher ones with bigger steam boilers but only slightly. With high efficiency direct vent hot water boilers, I think you're over 96%, it keeps creeping up by a small percentage each year. That's why no one puts in steam boilers anymore. I'd convert to hot water, but mine are all one pipe systems and I'd have to change all the pipes/radiators to go to hot water.
 
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I just switched from an oil furnace to propane. Not even close on fuel cost. Now what do I do with 100 gallons of treated #2?
 
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Well, I just found out that the unit was installed back in 1997. It has a hole in the burner and can't be repaired. She had it tuned up every year since they moved into the house back in 2002. The same company that tuned it every year is the same that installed it for the previous owner. She still has 250 gallons of oil in her tanks and has over $800 in credit with the oil company. At 85 years old, it seems going back with the least expensive oil unit would be the best option.

Thanks for all the information. If she was younger and I lived close, I would convert over to NG just for the fact of a lower cost to heat and possibly a better return when selling the house.
I agree - switching to NG would be best long-term, but at your mom's age I would just focus on getting the heat back on for her. One benefit of a boiler replacement is you have the opportunity to pick one that is appropriately sized, and perhaps a more efficient model than the pervious. Most contractors install oil boilers that are about 2x the size needed to heat the house. The right way to do it is to do a heat loss calculation on the house, but most installers will just pick a boiler the same size as the old one.
 
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I just switched from an oil furnace to propane. Not even close on fuel cost. Now what do I do with 100 gallons of treated #2?
Common issue. Check the net for oil removal services. Might be under hazmat services. They will pump it out and sell it to farmers with used oil furnaces or to truckers they know. The oil company that sold it to you will usually not take it back due to possible contamination issues. Not sure how much money they give you for the oil. Not much I’ll bet.

I had an old mobile home removed off a rec property. The trucker just transferred the oil from the oil furnace tank into his diesel truck. No idea where the oil tank ended up.
 

JHZR2

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Go and take a look at the steam boilers you can buy. I think because of the nature of steam, I haven't seen one much about 82% let alone 90%. I still have a few steam boilers, they're about 70-120k BTUs, you might get higher ones with bigger steam boilers but only slightly. With high efficiency direct vent hot water boilers, I think you're over 96%, it keeps creeping up by a small percentage each year. That's why no one puts in steam boilers anymore. I'd convert to hot water, but mine are all one pipe systems and I'd have to change all the pipes/radiators to go to hot water.

Yes, but again we are talking mod-con vs a standard boiler (to raise steam you cant really condense...), without any recuperation. A regular hydronic boiler not designed to condense and modulate is going to have significantly worse efficiencies.

Here's a dual purpose boiler from Weil-Mclean. You can see that the steam vs NG efficiency numbers are much closer, after all, you need to keep heat to get the exhaust to go up the flue.

Screen Shot 2021-11-29 at 9.44.34 AM.png


Obviously a mod/con hydronic boiler that doesnt need to be concerned with condensation and flue gas temperatures doesnt have these issues.

My theory is that while the AFUE may be 2% off, the steam system may actually burn less overall because it doesnt have nearly the thermal mass to overcome before the system starts providing heat to the living spaces. I dont think I want to know how much water is in my all cast iron hydronic system.... Steam has half the pipes and a LOT less working fluid that needs to be brought to temperature (granted you have phase change going on, which is a significant energy use, but it is directly imparted in the living space assuming that steam gets to the radiators without condensing much in the pipes). The net result could be far less firing time. Much less firing time at 82% vs much longer firing time at 84% may result in lower overall consumption, slightly. Yes, the hydronic system's thermal mass will mean that it will keep radiating for longer after the system is off, but I think were splitting hairs. The steam system is also far simpler.

So my only point was that a traditional hydronic vs steam system isnt that far off. Mod Con vs steam is apples to oranges.

I run mod con in my 100 year old cast iron hydronic system. I suspect its better all around, as lower temperatures on all components probably is good for them... Note that my recommendation to OP is mod/con NG boiler... And Id do indirect hot water at the same time...
 
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Rat407

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Just if anyone is interested. They are able to replace mom's boiler today. Thankful for that since it is cold. They are installing a Utica Keystone. I'm not familiar with boilers so don't know how good it is, but like I said, thankful that they can do it today.

They could have done NG but it would take at least 3 days since they had to deal with the gas company and it being right after the holiday and the fact that COVID in this are is still an issue and the gas company office is a one man band.
 
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Steam is not efficient... is all about comfort when coupled with cast radiators. When we remodeled our house, 1950's ranch, we updated the original oil boiler (likely from 70-80s) with a modern gas mod-con boiler along with european panel radiators throughout the house and staple-up radiant tubing in the bathroom.

Went from a 125k+ to 55k Lochinvar unit (redid all windows, doors, air sealing and insulation of house) with indirect hot water. 6 yrs, 15k hrs on unit... no issues.

My parents in the same neighborhood, with a slightly larger and not as "sealed" as ours (I went overboard on all the details) house could easily spend $2500 on oil for the winter with setbacks... whereas we rock 67-70 day/night 24/7 and pay maybe $800 per winter for gas. Gas was ~ $2/CCF (taxes and all) in CT from Eversource, currently tracking at $2.4/CCF.
 
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Just if anyone is interested. They are able to replace mom's boiler today. Thankful for that since it is cold. They are installing a Utica Keystone. I'm not familiar with boilers so don't know how good it is, but like I said, thankful that they can do it today.

They could have done NG but it would take at least 3 days since they had to deal with the gas company and it being right after the holiday and the fact that COVID in this are is still an issue and the gas company office is a one man band.
Understandable. Also, with the increased price of natural gas it’s closer to being comparable.
 
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Steam is not efficient... is all about comfort when coupled with cast radiators. When we remodeled our house, 1950's ranch, we updated the original oil boiler (likely from 70-80s) with a modern gas mod-con boiler along with european panel radiators throughout the house and staple-up radiant tubing in the bathroom.

Went from a 125k+ to 55k Lochinvar unit (redid all windows, doors, air sealing and insulation of house) with indirect hot water. 6 yrs, 15k hrs on unit... no issues.

My parents in the same neighborhood, with a slightly larger and not as "sealed" as ours (I went overboard on all the details) house could easily spend $2500 on oil for the winter with setbacks... whereas we rock 67-70 day/night 24/7 and pay maybe $800 per winter for gas. Gas was ~ $2/CCF (taxes and all) in CT from Eversource, currently tracking at $2.4/CCF.
Hmmm,. The spot price for natural gas is over $5.00.
 
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Steam is not efficient... is all about comfort when coupled with cast radiators. When we remodeled our house, 1950's ranch, we updated the original oil boiler (likely from 70-80s) with a modern gas mod-con boiler along with european panel radiators throughout the house and staple-up radiant tubing in the bathroom.

Went from a 125k+ to 55k Lochinvar unit (redid all windows, doors, air sealing and insulation of house) with indirect hot water. 6 yrs, 15k hrs on unit... no issues.

My parents in the same neighborhood, with a slightly larger and not as "sealed" as ours (I went overboard on all the details) house could easily spend $2500 on oil for the winter with setbacks... whereas we rock 67-70 day/night 24/7 and pay maybe $800 per winter for gas. Gas was ~ $2/CCF (taxes and all) in CT from Eversource, currently tracking at $2.4/CCF.
Here you go.

18CDA026-C710-4940-A99B-F7B0764FCD77.jpg
 
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