Hi All,
I finally found a company that makes vented catalytic heaters for RV use! For us at least, this type of heater combines the best of both worlds – quiet, frugal DC power and gas consumption and low build up of humidity (since the heater is vented) and also, thermostat controlled. Unlike some older units, these heaters have interlocks built in to ensure they operate safely. The “Platinum Cat Heater” is offered by a small company in Olympia, Washington, called A&L Enterprises. They makes two sizes of the vented catalytic heaters. Their URL is http://ventedcatheater.com/index.html and phone number is (360) 446-5355; you can find more information. Since each heater is made to order you can probably find a configuration that works for your situation. Arnie the owner, was great at helping me determine the best set-up for their situation.

We’re using the larger 5200 BTU/hr model for our 17’ Burro (could barely squeeze it in under our counter). We set the thermostat at 60 degrees and can stay toasty all night. When I run the numbers on gas and power consumption (see the site for specifications), we ought to be able to run the heater for 80 hrs before we run our 20 gallon propane tank dry. The unit uses a very quiet fan that draws only 0.5 amps, and uses a piezo-electric igniter whenever the heater starts up.

I’m attaching a few photos of the final installation (left), cut-out wall and newly installed heater vent (upper middle), installed vent hose, gas line, 12 VDC and thermostat wires (upper right), lines and wires attached to heater prior to slipping the heater into place (lower middle) and thermostat location with heater below in background (lower right). All in all, it was pretty easy to install this myself.

We’re looking forward to extending our camping season now!

Steve & Dixie

Click to view attachment

I've been looking for something just like that! Thanks for the links!

Hi All :

The heater looks great (on their web-site),

BUT, I dont understand why the company does not add any info on PRICES !!

Maybe some one here has contacted them and could post price info..

Thanks

Dick Pack

Ham Radio : VE3HRP@ISP.COM

I had one of those in my 13.

The "low buildup of humidity" may be a bit misleading, a polite way of saying.. "You'll get humidity, but you may not need a wetsuit".

I found mine to be just as bad as any of the others out there. Might have been age, but...when I replaced with an unvented Olympian, I actually got LESS humidity.

It WAS smaller, and newer.. that may be where the contrast came in.

We have had a few discussions of this heater design before, triggered by the one in Gina's old Burro. As I recall, the heater is not fully vented: the (catalytic) combustion occurs in a space open to the inside of the trailer, and much of the exhaust is taken outside by a vent, but it does not have the complete isolation of a regular direct-vent RV furnace.

It also gets its combustion air from inside the trailer; a traditional home furnace does the same, but a typical direct-vent RV furnace (such as my Boler's Suburban) takes the air from outside. The home furnace setup is clearly not ideal, and current building codes here require a fresh air intake ending right beside the furnace to ensure there is enough air supply. Taking air from inside makes a fresh air source - such as an open window - more important. Despite comments on the Platinum CAT website, it does require a fresh air source into the trailer.

I do not think that it would make sense for a completely vented furnace to use catalytic combustion. This design is a sort of compromise between the design of a radiant catalytic heater and the design of a conventional furnace. Like any compromise, it might deliver the right balance of features for the application.

I assume that, like many small companies, A&L Enterprises probably does not want to maintain changing information - such as prices - on their website. It's a common problem for businesses without full-time computer staff.

Hi All,
I should've mentioned that the heater, when I bought it earlier this year, ran between the price of a furnace and catalytic heater - about $450. Oddly, it's the same price for either size.

As Brian mentioned, since the heater draws air from inside the trailer (hence an open window or vent is needed), then vents the combustible gases (including moisture released from the propane) outside, in theory there ought to be less condensation build up than when we used a Mr. Heater last winter. I'll be able to confirm this, this winter.



Steve

I'm brand new to self contained camping so bear with me, but the combustion process of propane produces H2O? Is this removing Oxygen from the camper or just heating ambient humidity and causing condensation? I plan on camping a fair amount this winter and want to know what I'm up against with my Casita's factory heater...

Combustion produces CO2 and water (or CO and water if insufficient oxygen is present) and also, of course, produces heat. The reaction is

Propane + 5O2 ---> 3CO2 + 4H2O

It removes oxygen from the camper (if it is using air from the camper, which it appears that this is, but it would be possible to have air provided from the outside.) In this case, since a window has to be open, air is being drawn into the heater to fuel combustion. However, it sounds as if the combustion product gases are being vented outside in the vented heater. In an unvented heater, water would be produced and might cause condensation.

On the other hand, drawing in air from outside, on a winter night in the NW, may also result in condensation on the windows, since it will probably be higher humidity than the heated indoor air. I wonder why the design does NOT have air vented in as well as out?

Bobbie

PS, this is what happens when I read the forum instead of working on a chemistry exam I'm supposed to be writing.

BENITA!!! Bobbie gets a beanie!

HI All,
Someone pointed out to me that the Plat Cat Heater uses a nichrome wire to ignite it (not piezo electric, nor pilot light), thus the 5 amp draw for a couple minutes every time the heater starts up.

Steve

Not knowing anything about "Amp Draw" this worries me but maybe it shouldn't.
After going off last week and again Duo-therm not igniteing, I am starting to look for an alternative.
I am sure Brian or someone else will tell me is the running of the fan on the Duo-therm more costly on my singel battery then this 5 amp draw for a few minutes
Gerry the canoebuilder

Casita Heater:

Kyle: You should not have a problem if you have a factory installed heater. They take the air they need for combustion from the outside and then vent the exhaust gases to the outside. One reason it is very important to keep those vents clear of mud daubers or other insects that might block the air intake or exhaust.

Thanks for the info! I wondered what all that power was for; a spark ignition system wouldn't use nearly that much or go for that long.


Since the regular furnace's fan is on whenever it is running, the energy consumption of that furnace will be much higher than the start-up energy plus the minimal exhaust fan consumption for the Platinum CAT.

My Suburban furnace draws enough that when its fan kicks on the lights in the Boler dim perceptibly... and stay dimmed as the fan runs. The voltage drop is presumably due to the primitive regulation of the converter not accommodating the current demand of the fan very well, but a similar effect occurs on battery power. At a low enough temperature the voltage drop is enough to keep my 12V fluorescent light from starting properly.

Thank Paul, that is what I was hoping.

And Bobbie for the Chemistry lesson. I think I knew that at one time. Off topic, but do other gases such as natural gas have the same water generating effect?

Actually, Steve has done me a great favor by posting his pic. I want to pull out the furnace in my Burro at that spot and put in a Wave 8 cat heater ($$$$$) on a door. The door will let me access more storage where the furnace was. The Wave heaters come with swivel fittings for just this.

I will do as I did in my 13 and bring in fresh using a tube and the old outside vent plate.

Essentially any fuel containing hydrogen will produce water on combustion, because burning means combining with oxygen, and hydrogen plus oxygen (in the right proportion) is water. That means any form of petroleum oil or gas (including propane, natural gas, kerosene, gasoline, etc), any alcohol (ethanol, methanol, etc), and that favourite fuel of the popular media, hydrogen.

This is only an issue if the combustion exhaust of the heater goes into the interior of the trailer ("unvented"). That's done by very few types of heater, mostly propane-fueled catalytic units (but also the Mr. Heater non-catalytic design) and kerosene heaters (rarely used in RVs).

HI All,
I did a bit of math to figure out theoretically, how long could we run our 6P12 heater on a 20 lb. tank of propane for, with a 110 Amp-hr battery. So, assuming we run the heater six times a night for 1/2 hour per cycle, the propane would run out after 26 nights, the battery after 55 nights. Each 1/2 hr cycle would consume 0.32 amp-hrs. and 0.125 lbs of propane. So, it should be pretty frugal for dry camping. We'll see if these figures bear themselves out this winter, though our mileage will vary depending on the other appliances we use.

Steve