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Topic: Gas furnace (heater) not really useful? (Read 13 times) previous topic - next topic
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Gas furnace (heater) not really useful?
Yahoo Message Number: 97847
Hi all,
 I noticed that several members have ditched their gas furnace to make room for additional battery compartment.

Is the furnace really that bad?  If so, why?

What do you do for heat when you're not plugged in?
 I too, might want to add a couple batteries for 82 LD FL.  I looking for a space that's convenient and safe.

Thanks,

Sam
Re: Gas furnace (heater) not really useful?
Reply #1 –
Yahoo Message Number: 97849
"Is the furnace really that bad?  If so, why? What do you do for heat when you're not plugged in?"

 Sam, the furnace is both an electricity and propane hog.  Fulltimers or those who travel extensively often opt for a catalytic heater, which uses no electricity and uses propane much more efficiently.  The furnace is great for when you want to quickly heat the LD.

Andrew 1999 TK
Andrew
2008 Rear Bath
(previously 1999 TK)
Re: Gas furnace (heater) not really useful?
Reply #2 –
Yahoo Message Number: 97852
"A. Thio"  wrote: ...the furnace is both an electricity and propane hog.  Fulltimers or those who travel extensively often opt for a catalytic heater, which uses no electricity and uses propane much more efficiently.
--- The Mr. Heater "Portable Buddy" (a radiant heater) is currently on sale at Northern Tool:

http://tinyurl.com/hs6cu
 Whatever the heat source, hanging a heavy, insulating "drape" between the living area and the cab helps a great deal to keep heat in (or out of!) the living area. Some folks use a blanket or a comforter and tuck one edge under the overcab mattress. I cut-to-fit and sewed a drape out of a double-thickness of heavy denim; the drape is very effective, easy to fold up and store when not in use, and washable.

Joan
2003 TK has a new home
Re: Gas furnace (heater) not really useful?
Reply #4 –
Yahoo Message Number: 97854
"I noticed that several members have ditched their gas furnace to make room for additional battery compartment. Is the furnace really that bad? If so, why? What do you do for heat when you're not plugged in? I too, might want to add a couple batteries for 82 LD FL. I looking for a space that's convenient and safe."

Sam

Some folks have removed their forced air heaters and installed Catalytic heaters in their place. I guess that this is mostly done when the original heater has failed and a new one is too expensive.
IMO, there is nothing that will produce as much heat as quickly as the force-air furnace, just what you want on a cold morning. A cat heater is great for supplemental heat but will never entirely replace our furnace.

Many yeas ago I installed two T-105 batteries to our 1983 22' FL, behind the front barrel chair. They lived in an airtight box that was vented to the outside.
Recently Steve (aq433) added two AGMs to his 1983 FL in the same place.
.

See Steve article on adding two AGM batteries to his 1983 22' FL battery upgrade.doc http://autos.groups.yahoo.com/group/LD_Enhancements/files/

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: Gas furnace (heater) not really useful?
Reply #5 –
Yahoo Message Number: 97855
To add to what others have said, I would probably buy a replacement furnace if ours failed beyond my ability to repair it. Even though we use our small cat 95% of the time as our sole source of heat, we also tend to camp most often in chilly to very cold weather, and I would not leave the cat on all night to prevent freezing temps or hypothermia due to potential issues when live combustion is occuring inside. I have recalibrated our thermostat to function in a lower range, so cycling on will occur as low as 40F. As others have said, on a cold morn, the furnace will bring comfortable temps in about 10 min, at which the cat can maintain. For such use, lower efficiency is not a concern.

As far as battery location, if not using AGM, then venting and drainage to the outside is important, and if not using a below-grade outside location, that means going through an insulated wall. I would not have thought there would be enough room to place batteries behind the barrel chair without having seen Larry's install on his '83. I opted for the size 31 AGMs for max power in a package with minimum width and height, but they fill the width of the available space. I vented our AGMs to the inside, since heat will be generated.

Steve
2004 FL
2013 Honda Fit
Re: Gas furnace (heater) not really useful?
Reply #6 –
Yahoo Message Number: 97858
Others have explained the pros and cons pretty well. I traveled for years in a 22' twin/king Lazy Daze that had one 3,000 BTU catalytic heater at the extreme rear of the coach, under the dinette table. When the 20-year-old furnace failed, I replaced it with a second cat heater, a 6,000 BTU model, mounted near the front of the coach.
(Incidentally, I don't recommend 6,000-BTU radiant heaters in these small coaches--they tend to overheat the small area they face. With radiant heaters, several smaller ones are better than one big one.)
 I spent one southwestern winter with this two-cat-heater setup before selling the coach. The setup worked OK, and it certainly economized on propane and battery power... but as Larry pointed out, radiant heaters don't do anywhere near as good a job of quickly and evenly heating the whole coach as a forced-air furnace does. Surprisingly, even using small fans to move around the air from the cat heaters didn't seem to help much.

My present 27' midbath rig has the standard furnace, plus one cat heater mounted up front, opposite the dinette. If the furnace died, I'd replace it with another furnace. If I lived in Mexico, I *might* be happy with just a couple of cat heaters--assuming I could find suitable locations for them, which is always a problem--but anywhere north of the border, I like having the option of the furnace, noisy and inefficient as it is. Based on my experience living with cat heaters as my only heat source, I see them as better suited to use as an auxiliary heat source.

Andy Baird http://www.andybaird.com/travels/
Andy Baird
2021 Ford Ranger towing 2019 Airstream 19CB
Previously: 1985 LD Twin/King "Gertie"; 2003 LD Midbath "Skylark"
Re: Gas furnace (heater) not really useful?
Reply #7 –
Yahoo Message Number: 97861
Like so many other appliances "RV" (think lack of inexpensive thermometer on the fridge), the mfg's try to save every nickel they can. A proper furnace would, at the least, have a "soft start" feature where the fan comes up to speed slowly and tapers off at shut down too. That way it would not be so likely to wake a light sleeper.
 Like our domestic auto industry, their focus seems laser sharp, though unfortunately only taking in the short term bottom line. Out of focus entirely is the "how can we make this a better value for the consumer".

bumper
bumper
"Yonder" '05 MB
"WLDBLU" glider trailer
Re: Gas furnace (heater) not really useful?
Reply #8 –
Yahoo Message Number: 97862
Thank you all for your inputs.  Mine still works fine and does heat up the coach in a hurry.  As for batteries' location, thanks Larry and Steve for the suggestion.

Sam
Re: Gas furnace (heater) not really useful?
Reply #9 –
Yahoo Message Number: 97865
Hi Sam,
 I spent time and effort getting my furnace working then the first time I really needed it in the middle of a very cold night I couldn't get it to light as there wasn't enough battery to power the fan thanks to the funky converter you also asked about which ruined the battery by overcharging it and boiling off the electorlyte.
 So we got out our Coleman catalytic heater that runs on bottled gas and it saved our cold selves that night. There are three pages of them on ebay today.
 With a stove and an oven you don't need a heater. A clay pot on a stove burner radiates heat real well. Have a window open for a vent or two windows.

I'll address your electrical issues in that post.
Michelle 1982 22 foot rear lounge
Re: Gas furnace (heater) not really useful?
Reply #10 –
Yahoo Message Number: 97868
Quote
With a stove and an oven you don't need a heater. A clay pot on a
stove burner
 
Quote
radiates heat real well. Have a window open for a vent or two windows.
Michelle:  Good idea about the clay pot!

Quote
I'll address your electrical issues in that post.
Michelle 1982 22 foot rear lounge
Thanks.  I look forward to reading it.

Sam
Re: Gas furnace (heater) not really useful?
Reply #11 –
Yahoo Message Number: 97870
I cannot imagine using the stove, pot or not, for heat while sleeping. More risk than I'm willing to take.

bumper
bumper
"Yonder" '05 MB
"WLDBLU" glider trailer
Re: Gas furnace (heater) not really useful?
Reply #12 –
Yahoo Message Number: 97872
"I cannot imagine using the stove, pot or not, for heat while sleeping. More risk than I'm willing to take."
 I'm with Bumper. While *in theory* it might be safe to do this if you left a window or vent open as Michelle suggested, it's way to easy to forget--with potentially fatal results. For the same reason, I never leave a cat heater running overnight, open vent or not. Carbon monoxide poisoning is such a stupid way to die... stupid because it's so easily avoidable.

Andy Baird http://www.andybaird.com/travels/
Andy Baird
2021 Ford Ranger towing 2019 Airstream 19CB
Previously: 1985 LD Twin/King "Gertie"; 2003 LD Midbath "Skylark"
Re: Gas furnace (heater) not really useful?
Reply #13 –
Yahoo Message Number: 97875
I recall seeing warnings not to use the stove or oven as a heater.  A catalytic heater completely burns the propane while a stove or oven does not.  Jack
Re: Gas furnace (heater) not really useful?
Reply #14 –
Yahoo Message Number: 97877
"A catalytic heater completely burns the propane while a stove or oven does not."

You're right that all manufacturers warn against using stoves as heaters, but the problem isn't incomplete combustion--it's the carbon monoxide created by combustion. Any unvented propane-burning device, including a stove, is a CO risk.
 Catalytic heaters are safer, because no combustion takes place; they use a platinum-catalyzed oxidation reaction instead. Under normal circumstances, they emit little or no CO. But if starved for oxygen--e.g., when operated without any venting--even a cat heater can generate some CO.
 By contrast, the furnace is safe because all of its combustion fumes are vented to the outside--in fact, it has a separate blower that *forces* them outside. Its flue gases never mix with the heated air.
But of course this is exactly why a furnace is inefficient: about half of the heat it produces gets blown right out the exhaust port.

Andy Baird http://www.andybaird.com/travels/
Andy Baird
2021 Ford Ranger towing 2019 Airstream 19CB
Previously: 1985 LD Twin/King "Gertie"; 2003 LD Midbath "Skylark"
Re: Gas furnace (heater) not really useful?
Reply #15 –
Yahoo Message Number: 97880
Given a clean catalyst bed and sufficient oxygen there will be esentially no CO produced...thats what complete combustion includes.
I have never run my cat heater overnight, I have a working CO detector and alway have two windows and/vents opened, usually at different heights.  Jack
Re: Gas furnace (heater) not really useful?
Reply #16 –
Yahoo Message Number: 97881
Quote
"I cannot imagine using the stove, pot or not, for heat while sleeping. More risk than I'm willing to take."
 I'm with Bumper. While *in theory* it might be safe to do this if you left a window or vent open as Michelle suggested, it's way to easy to forget--with potentially fatal results. For the same reason, I never leave a cat heater running overnight, open vent or not. Carbon monoxide poisoning is such a stupid way to die... stupid because it's so easily avoidable.

Andy Baird http://www.andybaird.com/travels/
Thanks, Andy.  Yes, I'm very well aware of CO danger.

Sam
Re: Gas furnace (heater) not really useful?
Reply #17 –
Yahoo Message Number: 97882
wrote:
 I cannot imagine using the stove, pot or not, for heat while sleeping.
More risk than I'm willing to take.
--- IMO, using a "clay pot" over a stove burner to heat the interior of the rig is likely to produce the same result as building a fireplace and chimney out of river rocks! YMMV.

Joan
2003 TK has a new home
Re: Gas furnace (heater) not really useful?
Reply #18 –
Yahoo Message Number: 97883
Quote
Given a clean catalyst bed and sufficient oxygen there will be esentially no CO produced...thats what complete combustion
The key is sufficient oxygen - and note that the danger of asphyxiation from CO2 by accidentally leaving everything closed is greater with a well-designed cat than CO poisoning. However, the cat bed will over a long period of time likely produce higher levels of CO due to contamination. In general, running a non-vented external combustion device of any sort when not awake during operation is a risk we aren't willing to take.

Steve
2004 FL
2013 Honda Fit
Re: Gas furnace (heater) not really useful?
Reply #19 –
Yahoo Message Number: 97884
Hi Sam,
 When I bought my 82 all the wires were disconnected from the fuse panel because there was a short somewhere and the previous owner didn't know how to deal with it. I got everything up there fixed but the battery converter switch. I never quite understood that but now it doesn't matter because I removed the converter and freecycled it to someone for their boat.
 At this time I'm not even using the battery/converter switch and have a good automotive battery charger directly clamped to my batteries when needed while I continue to work on the electical system.
 To address your issues you first need something to measure voltage whether it's a digital meter, an analog meter or simply a 12 volt light bulb with two wires attatched.
I have such a bulb
Re: Gas furnace (heater) not really useful?
Reply #20 –
Yahoo Message Number: 97886
I wouldn't use the stove or any heater for sleeping. We have five dogs to keep us warm.
Before dogs though I have slept with hand warmers, one between the feet and one between the knees will help on a freezing night. A hot water bottle also works wrapped in a cloth bag so you can get it real hot, not boiling though as I ruined a hot water bottle that way.

Michelle * http://safoocat.blogspot.com/%c2%a0 * http://flickr.com/photos/safoocat/ * http://amazon.com/shops/safoocat
As an Amazon Associate Lazy Daze Owners' Group earns from qualifying purchases.
Re: Gas furnace (heater) not really useful?
Reply #21 –
Yahoo Message Number: 97887
"In general, running a non-vented external combustion device of any sort when not awake during operation is a risk we aren't willing to take."
 Same here. Not to beat this to death, but here's an example of what I meant when I said in an earlier post that even if you leave a window or vent open, running an unvented propane appliance can be dangerous.
A year or two ago, a young couple was tent camping on a chilly night, and brought a propane heater into the tent. They were careful to leave a flap open for ventilation, though, so they were safe--they thought.
But in the middle of the night, a gust of wind blew the flap closed.
Both campers were found dead the next morning.
 Well, our RV windows won't blow closed, but... suppose you decide to let the stove or cat heater run overnight, but you're careful to leave a window cracked open. Fine, only in the middle of the night your spouse or your child is awakened by a cold draft. Muttering "What idiot left the window open?", they shut it. And that's the end of the story for everybody in that coach.
 You can think of other, equally likely scenarios, I'm sure. When your life depends on something as simple as remembering to leave open a window, things can easily go dreadfully wrong.

By the way, changing the subject slightly--there's one other difference between RV furnaces and cat heaters that I should mention: all furnaces have thermostats, but most cat heaters do not. That means they don't automatically regulate their heat output; you have to turn them up and down or on and off manually.
 I don't mean to run down cat heaters. They're great for many purposes, especially boondocking. A cat heater does a wonderful job of taking the chill off a cool morning. But in sustained really cold weather, it's not a particularly good substitute for a furnace, at least in my experience.

Andy Baird http://www.andybaird.com/travels/
Andy Baird
2021 Ford Ranger towing 2019 Airstream 19CB
Previously: 1985 LD Twin/King "Gertie"; 2003 LD Midbath "Skylark"
Re: Gas furnace (heater) not really useful?
Reply #22 –
Yahoo Message Number: 97888
With plenty of solar panel and extra batteries, the substantial current draw of the furnace fan isn't so much an issue when boondocking. Cozy and comfy were my main reasons for installing the cat heater,  It's like a small fireplace mounted under the stove facing the dinette in our MB, "Yonder". Keeps the legs nice and warm and provides a good place to stand while dressing in the morning

bumper
bumper
"Yonder" '05 MB
"WLDBLU" glider trailer