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  #1  
Old 01-07-2003, 06:14 AM
kanicbird kanicbird is offline
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Don't use a oven for a heater?

This is a continuation of the how do I measure the level of propane gas tank. - This is for a vacation house.



Now I see that I use kerosene (furnace) faster then propane (hot water/cooking). In the winter a fuel delivery usually comes with a plowing surcharge to allow the trucks to get to the tanks that I wouldn't usually need.

I was thinking that maybe it would be a good idea to use the oven & furnace together for the initial heatup of the house upon arival (thermostat set at 50F when we are not here). Along with speeding the heatup to room temp, it would also use some more propane and save some kero.

Some other factors:

running out of propane is a major inconvienence and I have to wait for the truck (and most likely get plowed too).

running out of kero is disasterous if we are not there as the pipes would freeze and burst, if we are there we could use electric space heaters or even run to the gas station to get some fuel.
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  #2  
Old 01-07-2003, 06:18 AM
kanicbird kanicbird is offline
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Whoops

The questions are why are we told not to use an oven for a heater? Is it ok for such a limited use? any other factors that should be considered?
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  #3  
Old 01-07-2003, 06:21 AM
Mangetout Mangetout is offline
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You're talking about running the oven with the door open for an extended period of time?

I'm not sure how likely a scenario it is (or indeed whether it would be something the designers anticipated and made safe provision for), but...

An oven is generally designed to generate heat in a small enclosed space in a relatively short space of time, then maintain that temperature by cycling on and off; it is remotely possible that running the heating apparatus constantly (because the hot air is not contained and it never reaches the 'top up' cycle) could cause something (dunno; a heating element or a jet or something) to overheat and fail.
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Old 01-07-2003, 06:22 AM
Desmostylus Desmostylus is offline
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Pretend that you're roasting a big turkey for the first 3 hours after you arrive. Then turn it off.
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  #5  
Old 01-07-2003, 06:36 AM
Mangetout Mangetout is offline
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What you certainly could do would be to get some bricks (fire bricks would be good, as they shouldn't crack or explode), stack them in the oven (being careful not to overload it, naturally), turn it up to 'very hot' then when the bricks are nicely hot (taking all reasonable precautions to avoid injury and damage to property), remove the bricks and stack them on a heat-proof something (you could have a second set heating up in the oven while the first set emits warmth into your home).

OK, not one of my better ideas maybe.
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  #6  
Old 01-07-2003, 11:26 AM
BioHazard BioHazard is offline
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My first apartment was a tiny little converted motel thing. The only heating it had was those annoying electric baseboard heaters. The heaters were about twice my age and barely worked at all. Every night and every morning I'd turn on the burners and oven full blast for a couple hours and that would heat up the apartment nicely for several hours. Other than a *small* explosion that happened one time when the pilot light to the oven went out, there were never any bad effects.

My suggestion for you would be to go to Walmart and buy a couple Catalytic Camp Heater (Coleman BlackCat Portable Heater) and stock up on those little camping propane tanks. Just one of those would heat my apartment nicely. Each small tank lasted around 8 hrs on full blast and 16 hours on half blast. These heaters take around 20 mins to get to full heat. These heaters are perfectly safe for indoor use, they produce no CO2 or CO, but they do use up oxygene. These heaters are also very good as emergency heaters, and of course for camping.
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Old 01-07-2003, 12:23 PM
LordVor LordVor is offline
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The main thing with gas stoves with the door open and heating is carbon monoxide, IIRC. If you decide to do this, have a good CO2 detector.

-lv
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  #8  
Old 01-07-2003, 12:40 PM
Nametag Nametag is offline
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ALL gas-, kerosene-, propane-, wood-, coal-, and anything-else-organic-burning heaters produce CO2 and CO. The exact amounts and ratio of the two depends on conditions and fuel. These substances will suffocate you; in addition, CO is poisonous in its own right. Burning fuel in your living quarters will deplete oxygen, as well.

Heaters for use inside the home vent their exhaust to the outside; ovens do too, but only when they're closed (and properly installed). Ovens with their doors open, as well as camping heaters, kerosene heaters, and other unvented heaters will release their exhaust into the room. This is dangerous, potentially lethal, and incredibly stupid, as there's a label right on the thing telling you not to do it.

None of these warnings applies to electric ovens or heaters, naturally.
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Old 01-07-2003, 01:15 PM
BioHazard BioHazard is offline
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What I mentioned was a catalytic heater, it does not burn the fuel, it converts into another form, releasing heat. Ballard Fuel Cells use a similar proccess and they only produce electricity, heat, and water.
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  #10  
Old 01-07-2003, 01:39 PM
Nametag Nametag is offline
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Quote:
Originally posted by BioHazard
What I mentioned was a catalytic heater, it does not burn the fuel, it converts into another form, releasing heat. Ballard Fuel Cells use a similar proccess and they only produce electricity, heat, and water.
Who told you that, the salesman at Wal-Mart? This is from the Coleman Web site. The boldface is mine:
Quote:
The advanced platinum catalytic combustion system converts propane to heat energy at 850 degrees F. This temperature is below the ignition point of most flammable materials.

Catalytic heat produces fewer emissions. The catalytic process produces fewer gases such as nitrous oxide or carbon monoxide than conventional flame or radiant combustion at normal oxygen levels. But please remember that ALL combustion consumes oxygen. So while these heaters may be used indoors some ventilation must be provided to minimize oxygen depletion and also to prevent build-up of potentially dangerous gases.

In the Catalytic process, propane is brought into contact with oxygen in the air in the presence of a catalyst. The resulting chemical reaction generates heat.
The "resulting chemical reaction" is, of course, burning. And, of course, the Coleman site also has a blurb on the Black-Cat heater itself, which warns indoor users to use with "proper ventilation."
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  #11  
Old 01-07-2003, 01:49 PM
aahala aahala is offline
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I wouldn't know if your oven is like this, but in a typical electrical oven, one should use a "low" rather than a "high" setting for heat. You can burn out the heating element rather quickly on high, as the element turns on and off frequently on the high setting.
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  #12  
Old 01-07-2003, 03:42 PM
Gary T Gary T is offline
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...a catalytic heater, it does not burn the fuel..

Sure it does, as Nametag mentioned. What it doesn't do is burn the fuel with an open flame.

These heaters are perfectly safe for indoor use, they produce no CO2 or CO...

That's flat wrong. They burn propane, which is a hydrocarbon. The energy is produced by the hydrocarbon's hydrogen atoms combining with oxygen atoms from the air to form water. The carbon atoms, which have to go somewhere, also combine with oxygen to form carbon dioxide and carbon monoxide. It is impossible to combust a hydrocarbon without producing CO2. It is extremely difficult to do so without producing CO. The only way to have only water as a combustion byproduct is to burn only pure hydrogen.
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  #13  
Old 01-08-2003, 05:49 AM
kanicbird kanicbird is offline
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So I take it as it's no the best thing to do but for limited usage it's OK (as long as we get a CO det.) ALso lower the temp so it doesn't run continously.

The long term solution is to get a 2nd kero tank but I have to wait till the spring thaw 1st.
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Old 01-08-2003, 06:28 AM
Una Persson Una Persson is offline
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Well, let me make a guess here, since I've never actually seen a propane oven: when the propane oven door is shut, the exhaust from the flame in vented up and out of the house, correct? But when the door is left open (as in the case of trying to heat a room with it), wouldn't it end up venting somewhat into the kitchen? If so, that would be a good reason not to operate it that way.
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Old 01-08-2003, 09:19 AM
KneadToKnow KneadToKnow is offline
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Quote:
Originally posted by LordVor
The main thing with gas stoves with the door open and heating is carbon monoxide, IIRC. If you decide to do this, have a good CO2 detector.
It doesn't matter how good a CO2 detector you have, it won't sense carbon monoxide. For that, you still need a CO detector.

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  #16  
Old 01-08-2003, 09:32 AM
squid squid is offline
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The easiest soulution is to vacation in Florida where you don't need a heater.
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  #17  
Old 01-08-2003, 10:01 AM
even sven even sven is offline
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Our heater broke for a while and we had no real choice but to use the oven to heat the house. I didn't die. But one time I did accidently leave it on when I left the house for a while, which could have lead to disaster.
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Old 01-08-2003, 01:34 PM
pipper pipper is offline
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Quote:
Originally posted by LordVor
The main thing with gas stoves with the door open and heating is carbon monoxide, IIRC. If you decide to do this, have a good CO2 detector.
Door open or not shouldn't make any difference, as gas ovens are not vented to the outside like a furnace or hot water heater. All of the combustion emissions from the stove end up inside the house. I would think the main reason not to do this is that stoves aren't desgned to run at full blast indefinetely and you may end up damaging the stove. If you're willing to risk the stove, I would think it couldn't be much worse than a ventless gas fireplace (Of course, someone told me that the US is one of the few countries that still allow ventless fireplace. Most countries have banned them because of health concerns. I'd agree that you'd still want a CO detector)
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  #19  
Old 01-08-2003, 04:30 PM
kanicbird kanicbird is offline
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Quote:
The easiest soulution is to vacation in Florida where you don't need a heater.
But this would be to far away from the ski slopes
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  #20  
Old 01-08-2003, 04:49 PM
ZenBeam ZenBeam is offline
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Another reason not to use an oven or any unvented heater to heat a house long-term is that all the water vapor produced by combustion will increase the humidity level in the house, possibly leading to a mold problem. This wouldn't be a problem for k2dave's proposed usage, but I thought I'd mention it.
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  #21  
Old 01-08-2003, 06:40 PM
kanicbird kanicbird is offline
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Quote:
the exhaust from the flame in vented up and out of the house, correct?
No it's the same as a natural gas oven and for that matter an electric oven. No venting but ther is a stove hood vent fan that could be turned on (we usually don't though) to vent the oven as well.
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  #22  
Old 01-10-2003, 03:54 PM
BioHazard BioHazard is offline
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Sorry about that, I was thinking about the catylitc process in Ballard Fuel cells and applyed it to the Heater. Yes it was the sales person. I'm too trusting.

http://www.ballard.com
__________________
"A crimson pool, so warm and deep, lulls me to an endless sleep.
Your hand in mine, I will be brave, take me from this earth.
An endless night, this- the end of life.
From the dark, I feel your lips
and I taste your bloody kisses." :: Type O Negative.


"I COULD SHAKE MY TINY FIST AND SWEAR I WASN'T WRONG, BUT WHAT'S THE SENSE IN ARGUING WHEN YOU'RE MUCH TOO BUSY RETURNING TO THE LAVATORY." :: MegaHAL
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