Propex Heatsource furnace question

[kb7our]

Is the Propex really a catalytic heater? I believe, the Propex burns propane to heat the interior space's inside air pulled through the sealed heat exchanger, the combustion isn't heating the conditioned air directly. That said, I'd still vent the combustion gases to the outside and provide fresh outside air for combustion.

Mine sits outside the RTT when running. I provide a duct to bring the heated air in, and a return air duct back to the heater to reheat the tent's interior air.

BTW, I do use a CO detector in the tent when its running. With my unit outside, I'm more worried about a crack in the heat exchanger rather than the combustion buring all the oxygen in the tent.

Love my Propex!!!! I use 2 CO detectors to have a backup and don't generally run it while sleeping, although I probably would if necessary. The unit seems about as safe as a home furnace I have in the attic that burns NG and that I use while sleeping . Nothing is 100% safe - even a home furnace combustion chamber can leak into the blower (I had this happen and got CO poisoning through house vents) That's when the 12V heated mattress pad comes in handy!

From the Propex WEB site:

"Safety

Heatsource blown air heaters conform to the latest European standards for both the appliance and the electronics and during the rigorous testing the focus is very much on safety. The heaters also have to comply with an enhanced version of the Electro Mechanical Compatibility Directive to ensure they do not interfere with other electronics and that they are immune from interference by other electronics.
The intelligent electronics are continuously monitoring the operation of the heater to make sure everything is operating correctly and safely. This includes monitoring of the flame, case temperature, combustion airflow, gas solenoid valve and voltage. Should any of these stray outside of the predetermined levels, the heater will be switched off and the red light on the thermostat will indicate a fault by flashing a certain number of times."

 

[Haf-E]

The "catalytic" nature of these types of heaters causes the emissions to be mostly carbon dioxide (not so bad) - not carbon monoxide (much worse). That said, they do still require some air exchange to be safe.

Here is a good report on them - http://www.cpsc.gov/library/foia/foia05/os/co03.pdf - and an excerpt from the summary:

"When the catalytic heater was operated in a closed room (ACH ~ 0), the oxygen was depleted
from an ambient concentration of 20.9 percent to 8.8 percent. Because the catalytic heater can
deplete the O2 concentration to such low levels, the heater poses a serious risk of hypoxia. The
degree of hypoxia is further exacerbated by the moderate CO concentration and by an increase in
the carbon dioxide concentration that accompanied the depletion of oxygen.

As the oxygen decreased in the chamber, the catalytic heater became less effective at converting
the propane and oxygen to carbon dioxide and water vapor. This was reflected by an increase in
the hydrocarbon concentration in the chamber, which ranged from 1,050 ppm to 13,440 ppm (5 to
64 percent of the lower explosion limit of propane in air). The unreacted propane further
increases the degree of hypoxia."

I am pretty sure that the one used for this test did not have a oxygen depletion system on it - so that would make a difference.

I used one for years but found the amount of moisture it added to the air was a real problem - ended up feeling damp her in the Pacific NW and would add to mold and mildue issues.

Christopher

 

[Herbie]

Is the Propex really a catalytic heater?

NO.

Catalytic heaters got injected into this discussion as an alternative to the cost of a vented furnace. Neither the Propex or Espar vented heaters have any of the issues associated with combustion INSIDE the vehicle. Use of Propane, CO, and Smoke detectors is still recommended in case of some rare catastrophic failure or other problem, but externally vented heaters are in the opinions of most, VERY safe.

The debate going above is about whether or not catalytic heaters such as the Olympian Wave, etc. are "just as safe" or "less safe". Opinions vary.

 

[westyss]

seems there's some confusion here, definately the propex is not a cat heater, draws combustion air from outside and expels exhaust outside and burns propane just like a home furnace does, I think a pro's and con's list would be good.

Propex pro's: efficient, exhausts outside, recycles heated air inside, combustion air from outside, thermostat, can be left on overnight, provides a dry heat with no moisture as a by product, uses minimal power draw, light, self contained compact unit....

propex con's: Can be finicky with complicated electronic safety measure that are impossible to correct ( needs to be sent in ) some noise from intake and exhaust, fan noise but not too loud, needs adequate voltage or will shut down if voltage of battery too low, need to cut holes for mounting;intake exhaust,


Cat pro's: efficient, draws no power(unless a vented cat is used), inexpensive, no holes to cut other than propane feed, nice radiant heat, light,


Cat con's: smelly, emits moisture into the cabin air as a burn byproduct, uses "your" air for combustion, provides an uneasy feeling leaving it on overnight while sleeping,



ran out of pro's and con's but I'm sure others will chime in, for me, I have an hydronic system that will be installed in my rig but that uses power, I will be installing a wave 3 too, providing an inexpensive viable redundency system for heat, I must have good heat or I go exploring solo! Together I hope they make a good set up. had a propex 2800 in my westy, and use a small 3000BTU cat in my truck now (temporary )

 

[Gokracer1]

I am interested in a Propex for a RTT application. For those of you that have this heater and run for a RTT how is it really working out??

 

[mvbeggs]

I am interested in a Propex for a RTT application. For those of you that have this heater and run for a RTT how is it really working out??

Mine works great in the RTT. Highly recommend!

If you have more a specific question, I'd be happy to give you my $0.02.

 

[Gokracer1]

How do you have the heater set up like in a portable toolbox contraption like AT, or,???? I know they have a small amp draw, that was a concern of mine.
Most of my trips are to SW CO and Southern UT in the fall and early springs so temps do become an issue sometimes.
I know these things are very small all things considered. I have a Eezi Awn 1600 RTT that I would be heating. I know these are pricey little heaters compared to a lot out there but seem to be what I am looking for. I just want some real world feedback on them...

 

[mvbeggs]

How do you have the heater set up like in a portable toolbox contraption like AT, or,???? I know they have a small amp draw, that was a concern of mine.
Most of my trips are to SW CO and Southern UT in the fall and early springs so temps do become an issue sometimes.
I know these things are very small all things considered. I have a Eezi Awn 1600 RTT that I would be heating. I know these are pricey little heaters compared to a lot out there but seem to be what I am looking for. I just want some real world feedback on them...

Mine is setup in the AT "toolbox". Very compact. I carry 2 pieces of duct. One is the heavy duty duct, supplied by AT, for the supply air. The second is a piece of 4", flexible, downspout tube purchased at Lowes for the return air. I am using this with a Eezi Awn Globetrotter. I set the toolbox on the ground under the trailer. I run the hot air supply duct up to the tent near the sleeping platform. I run the return air at floor level in the changing room of the Globetrotter. The thermostat/switch is routed to a location near my head for easy access and adjustment. Works like a champ and will heat the tent enough to run you out.

I've used the heater in temperatures down to about 20F in 10-15 mph winds. Typically, we turn it on before going to bed and again in the morning before rolling out. We use pretty good sleeping bags so we haven't felt a need to run the heater all night. Takes 5-10 minutes to knock the chill off the tent. You can turn it up high enough that it will run you out of the tent. More than enough output to heat the tent.

Here's some pics of how my ducting is setup:

Black with yellow is hot air supply, the other is cold return air:

 

[Gokracer1]

Mvbeggs,

That is a pretty sweet setup. I would like to have it all contained in that unit like AT does it. Thanks for the pics and the info! I think this is going to be the way I go....

 

[jebers53]

Propex installed

Pulled the trigger and installed the Propex HS2000 in my tiger. Decided to leave the suburban blast furnace as I was able to find a nice location for the Propex under the couch. I would have chosen the higher btu HS2800 but with its longer length would have been a tight fit in the prefered location. I haven't tested in on a cold night but am impressed with its heat output and softer sound. The sound it makes is best described as like in the old days before cable tv, when you would fall asleep in front of the tv and wake up after the station had gone off the air, that static sound. Much quieter then the suburban.

 

[IdaSHO]

The beauty of the Propex heater is that the air source for the combustion chamber comes from outside the vehicle, and the exhaust is also vented outside the vehicle. The heated air does not come into contact with the combustion chamber as it uses a heat exchanger system.

That tech isnt new. :ylsmoke:

I enjoy my Carlson furnace every winter. Safe heat :victory:

Better yet, this 1970's tech doesnt even require electricity. Convection heat, and no control voltage needed at the burner.

 

[Borrego60]

They really work great and I am very happy with mine. Just ask anyone who came up to me on a cold mt night and ask how well it works. I just put the hot air tube into their jack and warm and toasty in about 20 seconds. They walk away saying I got to get one or they want to borrow mine.

 

[Yuman Desert Rat]

Hey! Mvbeggs, That looks familiar!!! You're right. This thing works like a champ! Thanks again. I have a 3 day trip coming up crossing the El Camino Del Diablo. I can't wait to make everyone freezing their junk off jealous!

 

[Yuman Desert Rat]

Gokracer1, thanks again for the drawers. They are the hub to my build in the LJ. I highly recommend the AT propex heater. It's expensive but well worth it!

 

[Dave Bennett]

They really work great and I am very happy with mine.

X2

We were up on Thomas Mtn in the snow on New Year's Eve. The Propex from AT really changes your attitude about winter camping