Will buying 10 oil filled space heaters even help this winter?

LegendsCreek

I have a large old farmhouse in Vermont with many sections, and rooms. The house is pretty well insulated but with the costs of oil I am looking for other options.

I don't want to buy anything like mini splits at this point and am just considering either buying 10 or more oil filled electric radiators, or perhaps two propane stoves that get about 30k btu each (I don't want to do this as it's much more work).

We generally keep the house very cool and in the low 60's all winter, but still spent almost 8k on oil last winter. Will getting a bunch of these oil filled space heaters actually make an impact, or will it be a giant waste of time and money? Our electric is all updated and our panels can handle the load.

Also, I don't see any of those oil filled radiators that are larger and more than 1500w. Do they even exist?

Thanks!

Hot_water_fan

Run the conversions:

Electric resistance $/MMBtu = $/kwh * 293
Electric Heat pump $/MMBtu = $/kwh *293/COP
Oil Heat $/MMBtu = $/gallon * 7.25 / COP
Propane Heat $/MMBtu = $/gallon * 10.93 / COP

Ballpark COPs are 2.5 to 3.5 for heat pumps, .8 to 1 for Oil and propane in central heating applications, probably less for a propane stove. Electric resistance COP = 1 so I left it out.

The electric radiators are slightly different depending on how you use them: if you heat only some rooms to the original temp, the heat might be more expensive per BTU but you'll be heating less space so total BTUs may decrease. That said, the oil thermostat determines if the system runs, so if it's on and that room is calling for heat, you're paying.

EdTheHeaterMan

Oil filled space heaters are just electric resistance heaters. The elements are inside the oil filled radiator. The feel of a hydronic radiator is somewhat more comfortable that the feel of a infrared toaster coil, glowing at you over extended time frame. The math is still the same. Electric resistance = COP of 1 wether it is in oil or not in oil. so follow @Hot_water_fan math assignment above.

Your answers will be graded by your wallet.

Jamie Hall

Keep in mind that an oil filled space heater with a power output of X watts -- say 1500 -- produces exactly the same amount of heat for each watt used as any other electric resistance space heater -- say, for example, a 40 dollar milk house heater. Distributed differently, perhaps -- some heaters are convection, some have fans, some are radiant -- but the same amount of heat. Just because it is oil filled doesn't produce more heat per watt.

They may or may not save any money -- more likely not, unless you use them for very localized situations.

LegendsCreek

Thank you for all the comments. I will try and figure out the math on those later. I was leaning more toward the oil filled heaters because they are said to be much safer and they retain their heat.

Hot_water_fan

Heat retaining means heavy more or less. If the heaters are on, weight doesn't matter much. It matters more if the radiator is on 5 minutes per hour. If it's on 60 minutes per hour, it's useless.

hot_rod

the oil filled versions will give you some radiant heat, heating objects, like you, not air like the fan type. So comfort may be better with an oil filled radiator instead of a fan coil.

ChrisJ

For cheap portable electric heaters the oil filled radiators are my favorite.

But the small cheap ceramic ones do just fine as well. But those are like comparing forced air to radiant.

Jamie Hall

@hot_rod 's and @Hot_water_fan {s comments are both correct -- but the oil filled types aren't really much safer than any other good quality electric heater, and don't make the mistake of thinking that just because they retain the heat -- which they do -- they are more efficient. They aren't.

EdTheHeaterMan

Thank you for all the comments. I will try and figure out the math on those later. I was leaning more toward the oil filled heaters because they are said to be much safer and they retain their heat.

I can't help it. This discussion about holding heat must be inserted here!
https://forum.heatinghelp.com/discussion/comment/1709914#
One of my better diagrams are herein!

JK_Brown

Look a youtuber Matthias Wandel's video 'Oil filled heaters: 600 watt heaters pretending to be 1500 watts' for the good the bad, the ugly on these heaters. Actual channel is Matthias Random Stuff. The heaters are a CALROD type heating element with two elements in an oil bath that rises in the fins to dissipate the heat radiantly and through convection through the fins. The flaw is that these things cut out on over temp when running on high rather than by the thermostat leading to early failure. But rewired, they are good 350/900 watt heaters that will likely have long on-times giving more continuous sense of heating.

They don't make them at higher wattages as all 120vac plug in heaters are limited to 1500 since they can be plugged into a random outlet circuit, likely 14 awg/15 amp. The danger of these heaters is that they can run for a long time thus stressing the wiring. A 240vac heater of higher output needs to move the heated medium, water, air, oil, faster to dissipate the heat at the rate it is being generated.

An alternative are these newer to the US market wall mounted, electric heated panels.

If you just want your own comfort when sitting, you can use low wattage local heating such as the heat lamps they use with lizards and a brooding lamp putting 100w right on you. We lost this local heating when we did away with incandescent bulbs. This local heat source is useful for older people who find radiant heat more pleasing and are stationary for long periods.

GGross

EdTheHeaterMan said:

Thank you for all the comments. I will try and figure out the math on those later. I was leaning more toward the oil filled heaters because they are said to be much safer and they retain their heat.

I can't help it. This discussion about holding heat must be inserted here!
https://forum.heatinghelp.com/discussion/comment/1709914#
One of my better diagrams are herein!

It truly is a masterpiece

hot_rod

The oil filled are nice in RVs also as they are mostly quiet. When you are on someone else's shore power, they are best:) If you even jiggle mine it trips off.

Anything with a fan also moves dust, pet hair, etc.

Jamie Hall

But just keep in mind: a watt is a watt is a watt, and it makes no difference what fancy case it is in or what fancy fans or fins it has.

Direct radiant is a different experience from convection from fan forced. That you may need to consider. But all of them provide the same number of BTUs per watt.

Jersey2

Is electric heat now cheaper than oil heat? Traditionally electric heat was the most expensive.

Jamie Hall

Jersey2 said:

Is electric heat now cheaper than oil heat? Traditionally electric heat was the most expensive.

Depends on where you live, and what your oil and electric prices are. Some places electric is very cheap. Other places electric is horrendous. You have to compare BTU to BTU (convert watt-hours to BTU).

hot_rod

You need to plug in cost numbers that are used in your area.
The crapshoot is how much will they increase? How quickly?

https://coalpail.com/fuel-comparison-calculator-home-heating

WMno57

Jamie Hall said:

But just keep in mind: a watt is a watt is a watt,

A watt is a watt, until it is not.
Coal is coal, until it is rolled.
Oil is oil, it won't spoil.
Bio Diesel is tasty, and it will spoil.
The Bolt is green, it runs on the Sun.
This was fun, and now I am done.

JakeCK

I'd be more concerned about the safety of running 10 oil filled space heaters. That's going to be hard on the buildings wiring, and unless you have 200amp service you are going to be pushing your service panel pretty close to it's rating and in fact if most of those heaters end up on the same leg it's going to be lights out. Not to mention if you have any other high draw appliances such as a water heater, dryer, stove...

Robert_25

Most of Vermont has fairly high electric rates. Unless your local rates show that electric is a good option in the calculations above, I would limit your use of electric heat to small areas that you want warmer than the rest of the house, like a bathroom.

Dave Carpentier

In Ontario, we can choose to use time-of-use electricity pricing.
At night (7pm-7am) its noticeably cheaper.
(on the flip side, during the day it's more expensive than just going traditional usage pricing)

When you say large old farmhouse, but it's well insulated ?
How about the windows ? Windows bleed a lot of heat.
Clear plastic shrink film works pretty good, but if you dont mind blocking out some windows on back of house or such, fill the window space with insulation and seal it with regular 6mil plastic.. now it's nearly as good as a wall section.

ChrisJ

JakeCK said:

I'd be more concerned about the safety of running 10 oil filled space heaters. That's going to be hard on the buildings wiring, and unless you have 200amp service you are going to be pushing your service panel pretty close to it's rating and in fact if most of those heaters end up on the same leg it's going to be lights out. Not to mention if you have any other high draw appliances such as a water heater, dryer, stove...

It's only 125A @ 120V.
Seems completely reasonable for a bunch if plug in heaters running while people are sleeping, doesn't it?

I really hope we're not going to see more fires and deaths from things like space heaters and charcoal grills in homes this winter.......

JakeCK

ChrisJ said:
a bunch if plug in heaters running while people are sleeping

My worst nightmare right there.

ChrisJ

JakeCK said:

ChrisJ said:
a bunch if plug in heaters running while people are sleeping

My worst nightmare right there.

In my own situation I would have little issue with sleeping with many heaters on.

However,
I only use spec grade or industrial grade receptacles in my house. If a receptacle is ever found to be questionable or loose it gets replaced. We keep an eye on things and If a cord or plug end is found to be running unreasonably warm it is inspected and dealt with.


I know for a fact this is not normal or common in residential situations.

mattmia2

ChrisJ said:

JakeCK said:

ChrisJ said:
a bunch if plug in heaters running while people are sleeping

My worst nightmare right there.

In my own situation I would have little issue with sleeping with many heaters on.

However,
I only use spec grade or industrial grade receptacles in my house. If a receptacle is ever found to be questionable or loose it gets replaced. We keep an eye on things and If a cord or plug end is found to be running unreasonably warm it is inspected and dealt with.


I know for a fact this is not normal or common in residential situations.

The heater itself is still in most cases the bare minimum that would pass the listing test or possibly a modified design that was argued didn't need retesting.

ChrisJ

mattmia2 said:

ChrisJ said:

JakeCK said:

ChrisJ said:
a bunch if plug in heaters running while people are sleeping

My worst nightmare right there.

In my own situation I would have little issue with sleeping with many heaters on.

However,
I only use spec grade or industrial grade receptacles in my house. If a receptacle is ever found to be questionable or loose it gets replaced. We keep an eye on things and If a cord or plug end is found to be running unreasonably warm it is inspected and dealt with.


I know for a fact this is not normal or common in residential situations.

The heater itself is still in most cases the bare minimum that would pass the listing test or possibly a modified design that was argued didn't need retesting.

The biggest issue I've seen with oil filled radiators is the thermostat arcs a lot and the contacts fail.
The cord runs a bit warm, but it's dissipating heat into the same space as the heater and the insulation seems to hold up well.

It's not just about passing the listing. They don't want class action lawsuits either.