How long will heating oil last before it goes bad?

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fire_man

Minister of Fire
Feb 6, 2009
2,676
North Eastern MA
We have one oil tank that supplies heating oil to a hot air furnace and to a separate oil fired domestic hot water furnace. We use zero oil for the hot air furnace since we heat with 100% wood.The hot air furnace is really just for backup heat. We go thru about a tank of oil every two years for the domestic hot water, so the oil gets refreshed. The question is, if I swap out the oil fired water heater for an electric heat pump, will the oil eventually go bad?

The water heater is almost 40 years old so I know it's days are numbered and it seems to make the most sense when it dies to replace it with an electric heat pump rather than another oil fired heater.

In the old days, I understand heating oil was 100% dino oil and really had no shelf life, but all the oil companies I have called are now mixing a high percentage of Biofuels into their heating oil which are evidentally not as stable, even if you add stabilizers. I don't want to end up with 100's of gallons of toxic waste. I suppose the real answer is to ditch the oil fired hot air furnace and install min-splits for the backup heat but I hate to spend that kind of money when we burn 100% wood.

Just looking for thoughts - seems like my only choices are to swap both furnaces to mini split/heat pump or to replace the hot water heater with another oil fired unit.
 
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EbS-P

Minister of Fire
Jan 19, 2019
3,530
SE North Carolina
Google says 18-24 months. You’ve gotten by doing 24. Maybe and addictive will extend it. But I think bigger issue is relying on an old system that doesn’t get regular use.

You have forced air ducts I’d look at a cheap AC/ heatpump. Nothing fancy look at the Mr cool line up. I know it’s not cheap but you need to convince your insurance you have a non wood system (probably). Depending on layou you might get by with a single unit.

I love my 80 heatpump water heater. We have a big family and can run it out of hot water but we have to try. 3 baths and dishes in an hour or two. Remember you are heating the water with your wood heat. Really the efficiency drops off at temps below 60.

Part of me says the cheapest solution to install is electric baseboard heaters. Might be expensive to run but how often do think you will need them?

If you can spend the money the best solution is a forced air heatpump/AC system. I love mine. Cost very little to run when temps are 40 or above. Gotta say AC in New England is going to a regular thing unless you are at elevation. If duct work needs work it’s probably not at all worth it.


Evan
 

fire_man

Minister of Fire
Feb 6, 2009
2,676
North Eastern MA
Good points.

How inefficient are the heat pump domestic water heaters when the basement drops to 40F? Our basement gets down to 40F during cold winters. I would assume the heating element would be kicking on all winter. Our eletric rates are crazy high around here.
 

EbS-P

Minister of Fire
Jan 19, 2019
3,530
SE North Carolina
Good points.

How inefficient are the heat pump domestic water heaters when the basement drops to 40F? Our basement gets down to 40F during cold winters. I would assume the heating element would be kicking on all winter. Our eletric rates are crazy high around here.
Probably efficient enough in the other months to make it still a smart choice. I’m going to just take a wild guess and the COP drops to 1.5-2 and that still makes more efficient than running on elements but you have to figure in the recovery time. Probably cheaper than oil even with your high rates when you figure in total operating cost over the lifetime of the unit.

One option and I’m not saying it’s good nor have thought out all the details but I had a thread on it is using the existing ductwork to supply intake air to the unit.

Search for my threads if you want to read up on it.
 

fire_man

Minister of Fire
Feb 6, 2009
2,676
North Eastern MA
It makes sense to supply the heat pump water heater with ducted air from the warmer rooms above, rather than from a cold basement. I don't know much about the technology, but it sure seems a no brainer that it should be something the designers figured into the installation.

Would I still need a dehumidifier in the basement if I had a heat pump water heater? That dehumidifier really adds to the electric bill.

I just called one oil company who said they do not add biofuel to their heating oil. They are even 50 cents/gallon cheaper.
 

EbS-P

Minister of Fire
Jan 19, 2019
3,530
SE North Carolina
It makes sense to supply the heat pump water heater with ducted air from the warmer rooms above, rather than from a cold basement. I don't know much about the technology, but it sure seems a no brainer that it should be something the designers figured into the installation.

Would I still need a dehumidifier in the basement if I had a heat pump water heater? That dehumidifier really adds to the electric bill.

I just called one oil company who said they do not add biofuel to their heating oil. They are even 50 cents/gallon cheaper.
Depends on how much hot water you use. I went from 2 dumping both daily to one once every other day. But we made other changes too and have 5 kids. It helps a lot. But not a complete replacement but my basement is finished and one of the changes added 500 sq ft and vapor barrier under 1000 sq ft of LVP. Remember the condensate is free heat!
 

brenndatomu

Minister of Fire
Aug 21, 2013
7,513
NE Ohio
I just called one oil company who said they do not add biofuel to their heating oil. They are even 50 cents/gallon cheaper.
The difference is they now remove most of the Sulphur (EPA mandated)
It will not last as long as it once would, but it can still last a long time...it depends a lot on where and how its stored too...is it in an underground tank? Water leaking in and condensation buildup over time can make matters worse too. They make products to stabilize the fuel and also prevent/kill algae too...low sulphur fuels can grow algae, that wasn't an issue before.
I have a tank that I have been nursing along since 2012, no issues...but it is stored indoors, and I have put additives in it too.
Would I still need a dehumidifier in the basement if I had a heat pump water heater?
Depends on how wet your basement is, and how much hot water you use...for us, yes it keeps the basement dry enough in the summer with no humidifier usage...family of 4.
 
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fire_man

Minister of Fire
Feb 6, 2009
2,676
North Eastern MA
One thig I like about the oil fired hot water heaters is they tend to last longer than other types, at least from what I've heard and experienced. Mine is still running after 37 years of service.
 

salecker

Minister of Fire
Aug 22, 2010
1,875
Northern Canada
Up North we need to worry about fuel gelling in the winter so all our heating fuel is good too -50 without gelling.
I have trucks and equipment that sits for years and have no issues.My D7 sat for over 10 years and fired right up.
Add a good conditioner make sure there is no water intrusion.
When i started burning waste oil at my shop,i was given 3 drums of diesel from...? There was a good chance it was from the forties.It was in US Army drums and was found off the original Haines Road built in the forties by the US army.
He tried to use it in his equipment and plugged his filters.You could see the growth of alge on the inside of the drums.
The Reznor waste oil furnace slurped it up no issues.
 

EbS-P

Minister of Fire
Jan 19, 2019
3,530
SE North Carolina
here’s the situation I would want to avoid. Winter time trip. All packed and ready to go, kick over to oil furnace and it’s a no go or not working reliably enough to feel comfortable leaving. You know your system better than anyone and what it would take to get a repair. It’s just planning ahead. As long it’s working when you leave and have a good trip insurance covers any miss haps considering depreciation of course and minus deductible.
 

Highbeam

Minister of Fire
Dec 28, 2006
19,997
Mt. Rainier Foothills, WA
If you keep the oil water heater can you alternate which oil tank you draw from? That plus keeping an annual "tune up" on the oil furnace might be the plan.

I would ditch the oil entirely if you're going to ditch the oil water heater. Even a cheap propane furnace should go right in and the propane has no shelf life limitations. The tank of propane on site offers energy security. Also cheap is a basic resistance electric furnace.

I too have heated 100% with wood for many years and it's hard to spend much money on a backup system but I believe it's important to have one. If the oil furnace goes away I would spend the permium on a mr cool heat pump system. They're pretty amazing.
 
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fire_man

Minister of Fire
Feb 6, 2009
2,676
North Eastern MA
If you keep the oil water heater can you alternate which oil tank you draw from? That plus keeping an annual "tune up" on the oil furnace might be the plan.

I would ditch the oil entirely if you're going to ditch the oil water heater. Even a cheap propane furnace should go right in and the propane has no shelf life limitations. The tank of propane on site offers energy security. Also cheap is a basic resistance electric furnace.

I too have heated 100% with wood for many years and it's hard to spend much money on a backup system but I believe it's important to have one. If the oil furnace goes away I would spend the permium on a mr cool heat pump system. They're pretty amazing.
There is one tank which feeds both furnaces.

I have both furnaces tuned up every other year. My thinking is the water heater gets used intermittently every day so it can go two years between tuneups. The backup heat really does not need many tuneups since its never used, but the way insurance companies work these days, I figured I'd better have a record that it's been regularly professionally maintained in the unlikely event we travel during the winter and the pipes burst due to a furnace problem.

I agree, I hate to spend $$$ on backup heat. It would make sense to ditch oil entirely if I did get rid of the oil water heater. I just have to weigh the cost of putting in propaine or a heat pump for the backup heat. What is MR cool heat pump? Is that Mini-splits?

Speaking of insurance companies, I just heard a story that a local homeowner was denied an insurance claim when a tree service she hired dropped a tree on her house. She found out too late that the tree service let their liability insurance expire. Her Insurance denied her claim since she did not perform "due dilegence" to hire an insured professional. It would have been better for her if a storm dropped the tree on her house.
 

Highbeam

Minister of Fire
Dec 28, 2006
19,997
Mt. Rainier Foothills, WA
What is MR cool heat pump? Is that Mini-splits?

Mrcool is a company that sells minisplits (I just in stalled one last week) as well as whole air handler heat pump replacements. These air handler systems are pretty awesome and I think one member on this forum detailed his installation experience with one. The air handlers use such a good heat pump that they don't need back up electrical resistance heaters in the duct even in the deep negative outdoor temperatures. However, you can pay a very small markup for an optional resistance heater in the air handler if you want and it will probably just sit there as backup. If your ducts are reasonably good then I would go with the air handler style. If you don't have ducting or the ducting sucks, then you can do like I did and go with a minisplit or three but be warned that not all minisplits can make heat when it's super cold and distributing that heat is harder without ducts.
 

fire_man

Minister of Fire
Feb 6, 2009
2,676
North Eastern MA
Mrcool is a company that sells minisplits (I just in stalled one last week) as well as whole air handler heat pump replacements. These air handler systems are pretty awesome and I think one member on this forum detailed his installation experience with one. The air handlers use such a good heat pump that they don't need back up electrical resistance heaters in the duct even in the deep negative outdoor temperatures. However, you can pay a very small markup for an optional resistance heater in the air handler if you want and it will probably just sit there as backup. If your ducts are reasonably good then I would go with the air handler style. If you don't have ducting or the ducting sucks, then you can do like I did and go with a minisplit or three but be warned that not all minisplits can make heat when it's super cold and distributing that heat is harder without ducts.
OK this is good info. That explains why my two neighbors who had baseboard hot water heat (no ducts) installed multiple mini-splits rather than an air handler. I have ducting (forced hot air) so it seems I would want to go with a hot air furnace powered by a heat pump which hopefully would also do AC. I did not know mini-splits had more limitations low temperature wise than the air handler. I assume by air handler you mean a central furnace powered by a heat pump.

My neighbor claims his minispiit works down to some insanely low outdoor temperature but it sounds like that is more the exception than the rule.
 

Highbeam

Minister of Fire
Dec 28, 2006
19,997
Mt. Rainier Foothills, WA
OK this is good info. That explains why my two neighbors who had baseboard hot water heat (no ducts) installed multiple mini-splits rather than an air handler. I have ducting (forced hot air) so it seems I would want to go with a hot air furnace powered by a heat pump which hopefully would also do AC. I did not know mini-splits had more limitations low temperature wise than the air handler. I assume by air handler you mean a central furnace powered by a heat pump.

My neighbor claims his minispiit works down to some insanely low outdoor temperature but it sounds like that is more the exception than the rule.

Here's the link.


Some minisplits can perform almost as well in really cold weather but none will use your ducts or offer electrical resistance coils just in case. Oh and these central units allow you to use air filters. Not on minisplits. Plus you don't have to look at the stupid indoor units on the wall.

78% of rated output at -22F sounds pretty good. I don't know how cold it gets at your home. These do of course offer AC which is really nice as temperatures continue to climb.
 

ABMax24

Minister of Fire
Sep 18, 2019
1,701
Grande Prairie, Alberta, Canada
I knew a guy that bought a 48ft ocean boat with 1000gal of well aged diesel in the tanks. He managed to put some additive in it, and using a portable pump and filter setup he circulated the fuel for about a week, clean enough to make it burn in the engine.

Might be an option, add some good additive, and maybe a circulator pump with filters?
 

EbS-P

Minister of Fire
Jan 19, 2019
3,530
SE North Carolina
do you have 200 amp electrical service?
 

Unextinguished

New Member
Aug 2, 2022
18
Vermont, northerly, USA
Even 100% dino oil can end up hosting microbes that can survive it and metabolize it and create goo. Does it happen often? Probably not. How likely is it to happen in any situation - probably not, but the odds probably rise as fuel sits, and if you at some point got a delivery that was already hosting some, odds might rise, and, apparently, once they are in your system, they kind of like to hang around. Some of the good fuel "911" type stuff (not at all sure if it is that specific one, you'd want to start reading labels' fine print) contain a fuel-specific biocide.

I am going to keep a Toyotomi oil water heater as a fall back; I already own it and it is a little beast of a unit. I plan to burn through what is left of my 275 gallon tank of oil in the relatively near term, and then consider buying smaller quantities to have on hand in smaller containers, and rotate the fuel stock to run the tractor, etc.
 

EbS-P

Minister of Fire
Jan 19, 2019
3,530
SE North Carolina
yes 200A service
You have options. Head down the rabbit hole!

I vote ditch the oil as soon as soon as you can pay for a heatpump. Just as a reference point compressor and blower are on a 60A and heat strips on an 80A breaker for a 3 ton unit.

MA have any rebates or incentives to swap out?
 

Highbeam

Minister of Fire
Dec 28, 2006
19,997
Mt. Rainier Foothills, WA
You have options. Head down the rabbit hole!

I vote ditch the oil as soon as soon as you can pay for a heatpump. Just as a reference point compressor and blower are on a 60A and heat strips on an 80A breaker for a 3 ton unit.

MA have any rebates or incentives to swap out?
The electrical needs of modern heat pumps are much lower. My current 2 ton heat pump could have been fed with a 20 amp circuit and 12 gauge wire. Like light switch wire!
 

fire_man

Minister of Fire
Feb 6, 2009
2,676
North Eastern MA
You have options. Head down the rabbit hole!

I vote ditch the oil as soon as soon as you can pay for a heatpump. Just as a reference point compressor and blower are on a 60A and heat strips on an 80A breaker for a 3 ton unit.

MA have any rebates or incentives to swap out?
MA has crazy high electric rates (25 cents/KWH). Seems everybody with a heat pump around here has solar. Solar only makes sense if I plan to stay in this house long term, which is uncertain.
 

fire_man

Minister of Fire
Feb 6, 2009
2,676
North Eastern MA
The electrical needs of modern heat pumps are much lower. My current 2 ton heat pump could have been fed with a 20 amp circuit and 12 gauge wire. Like light switch wire!
How much maintenance is required on these heat pump systems? I imagine it's less than my oil burner but the heat pump has more moving parts and is just plain more complicated.
 
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Tonty

Burning Hunk
Jul 24, 2017
120
Kansas
I
How much maintenance is required on these heat pump systems? I imagine it's less than my oil burner but the heat pump has more moving parts and is just plain more complicated.
I have a heat pump hot water system. Mine is located in our garage, which is wouldn’t recommend. It is nice to cool the garage off, and I find that with a small window A/C unit, it can make it quite comfortable to work in there in the heat of a Kansas summer. But the reason I wouldn’t recommend it is that it’s quite a dirt location. With that being said, I’ve had it 5 years, and the maintenance I’ve done is blow the filter out frequently (it’s easy to do), and I have taken the top heat pump portion apart to clean the coils as best I can once or so. That is also not a complicated project, just takes a little time. I would recommend a heat pump water tank. It works quite well and keeps up with a family of 7. I have it set in a schedule so that it briefly goes into high demand mode in the evening when we are taking showers, etc., otherwise it runs on the energy efficient mode and the element rarely comes on.
 

peakbagger

Minister of Fire
Jul 11, 2008
7,685
Northern NH
Biobore is one product for keeping microbes out of oil.