Poll, Propex function at 10,000 feet

[Outback Kampers]

Awesome! Wish I had a VAN that would get me TO a ski area out west!
_________________
Karl Mullendore
1990 Syncro 16" sunroof Reimo highroof conversion
1990 Westy Multivan 112i automatic
1992 LT31 Karmann Distance Wide 'La Tortuga'
2014 Touareg X TDI

[Jon_slider]

Karl serviced my Propex, replaced the gas valve and adjusted the spark gap.. Thanks!

I spent the night at 6000 feet altitude, at Squaw Valley, the heater worked every time!

Went snowboarding today, after that, the heater worked every time again!

Me so happy!

Moral of the story, if you are one of the people not getting 100% function, send it to Karl.

[Jon_slider]

I shipped the Propex to you today Karl.

The circuit board LED does stay lit at sea level at 46F outside, but not at 6000ft at 21F outside.

If you get a chance to test it, please see if you can find someplace with snow, thats when I really need it to work, I overnight at the Ski area in the van.

Happy Holidays

[Outback Kampers]

[Jon_slider]

> There are several possibilities, based on what you have observed:
> 1) Gas pressure too low or too high

I went to the trouble to set to 14wci, using the instructions on your site for a manometer

> 2) Ignitor contact erratically sensing the flame or is not directly in the flame path.

sounds likely, but we already replaced the ignitor last time

> 3) Partial obstruction of the gas jet

it works fine at sea level

> If you'd like to give me one more crack at it I think we can resolve this.

Thanks Karl!
Your customer service is excellent! fwiw, we already replaced the ignitor on this unit, but if you want to do it again, I will ship the unit to you, unless you just want to mail me the ignitor.

fwiw, Im at sea level this morning, its 46F outside, and very wet, lots of condensation, wet glass and wet grass. Propex has no problem igniting on 1st click attempt.

If the ingniter is not a user replaceable part, let me know and I will ship the unit back to you.

Thanks and Happy Holy Daze
Jonathan

[Californio]

I don't mean to hijack this thread, but why don't these have return air filters on them? With all the crap floating around the van you can imagine what they're going to look like inside in a few years. This shouldn't really affect the burner flame but still...I've often wondered.

Anybody rig up a non-obstructive filter for the return air?

[Outback Kampers]

[Jon_slider]

> Are you sure that the failure is a function of altitude, not temperature?

Great point, not sure yet, the places I go that have snow, are above 5000 feet.

> Ever try the thing at altitude during the summer?

Also a good question, no, I dont actually go to the ski areas during the summer, nor do I use my Propex during the summer.. will make a note to try that.

> Is it possible for you to disconnect the propane line at the heater and do a flow test the next time it won't light?

very good suggestion, Yes, that sounds like a good next thing to test.. The Propex is under the bench seat, no problem loosening the supply line nut at that point.. if I can make soapy water bubble by doing that, then it would seem to eliminate problems with my fuel line.. will report back next time Im somewhere that is freezing cold out and my propex fails.

Thanks for your suggestion.

> If you have moisture in the line it could be freezing and plugging up the line.

moisture inside the Propane tank and/or the propane delivery lines seems unlikely, but your flow test would answer that, thanks for putting your head to my problem

> I would disconnect the line at both ends and blow some compressed air through it and see what flies out.

another great suggestion, I will add that to the checklist, thanks

Im actually leaning towards remaking the whole propane delivery line... will report back after that

> t sounds like you frequently travel from low-altitude warm temps to higher altitude cold temps.

yes, I use my van to go snowboarding, but Ive done all I can to mitigate moisture issues in the airpath to the flame. Also, that variable was eliminated in this most recent failure report. The Propex had been working the night before, when I arrived at the ski area. It lit on its second click/attempt, and worked for several hours after that. However, at about 3am, I decided I was tired of listening to the noise, the heater was running non stop for what seemed like over half an hour, even though I had my top down, and my cab separated with a blanket behind the seats. It was 21F outside, and 50f inside. Point being the pipes were clear, and I did not drive through any snow or water after the heater turned off.

At 7am the temp outside was still 21F, and inside the van it was 25F. I was very comfortable under my down comforter. When I got up, I made a cup of tea and took the foto I posted. There is no problem I can tell with the propane delivery to the stove, hence at this point my suspicions focus on the fuel line to the propex specifically, as FNGRUVN has highlighted.

[?Waldo?]

It sounds like you frequently travel from low-altitude warm temps to higher altitude cold temps. That transition is perfect for heightened moisture condensation accumulating especially in areas of limited airflow. Perhaps other people do not typically experience those effects because they don't typically travel between those conditions.
_________________
I am a high-functioning autistic into VW diesels and Vanagons along with other things that are unrelated to this site.

[FNGRUVN]

Is it possible for you to disconnect the propane line at the heater and do a flow test the next time it won't light?

Andrew has a good point. If you have moisture in the line it could be freezing and plugging up the line. A small kink would compound the problem. There isn't much pressure after the regulator so a small chunk of ice would stay put.

I would disconnect the line at both ends and blow some compressed air through it and see what flies out.
_________________
"Democracy is two wolves and a lamb voting on what to have for lunch. Liberty is a well-armed lamb contesting the vote." - Benjamin Franklin

[Californio]

It seems to me that there only four variables outside the unit itself: the thermostat, the propane supply, the electrical current supply, and the exhaust/intake.

If you've eliminated those as possible failure points, then it can only be the Propex.

The question is, have you eliminated those?

Are you sure that the failure is a function of altitude, not temperature? Ever try the thing at altitude during the summer?

[Jon_slider]

> moisture issue

I think its possible, but, why do other people not have the problem? Karl already serviced the unit twice, it should have up to date parts in it..

fwiw, Im ending the battery test now.

I have 11.94 volts after 2 hours of running the stereo and the kitchen light. For 1 of those hours I had the Propex running non stop.

afaict, I dont have a battery problem. (test needs repeating in below freezing temps at altitude, in case battery level drops lower when cold)

my next move could be to replace the propane line, and make sure there are no kinks in the new one..

but, thats a pretty remote guess, that a kink in a propane line gets too small to pass gas at altitude..

I just dont know where else to go with this problem.. short of replacing the circuit board..

but, why do that when the problem is that it wont light at altitude and it consistently lights at sea level?

Ive been debugging this problem for at least 2 ski seasons now, and still no Love

suggestions always welcome

[?Waldo?]

I have zero experience with propex heaters and have never seen the inside of one so a few grains of salt are in order. Any chance that you have a moisture issue that is causing condensation that interferes with whatever is sensing the propane? The condensation could occur as you change temperatures from warmer to colder.
_________________
I am a high-functioning autistic into VW diesels and Vanagons along with other things that are unrelated to this site.

[Jon_slider]

> Can we assume there has been no water contact with the unit or physical damage?

true, the unit is dry, never been dropped, bought new from Karl

and it works at sea level

> Is the combustion chamber getting enough air? At altitude you need more air and less fuel. Just wondering if the combustion intake pipe is restricted or routed funny.

unobstructed, no ice, no snow, no water, no mud, no dirt, the pipes are clear, and installed per Karl's photos

and it works at sea level

> If it was the battery, wouldn't you get a low voltage error code. Three flashes of the led, I think.

good point.

In any case I went to Volks-Cafe and bought their Battery Minder. It shows 12.2 volts right now, with the cassette player on, and the kitchen light on.. Im going to check every hour and see if it ever goes below 10.5 volts. The Propex manual says the cutoff is at 10 volts.

So far, it does not seem to be a battery problem.

> Then the LED should come on and stay on.

yes, the LED on the circuit board flashes once when first turning on the thermostat, then the circuit board LED stays ON at sea level, after the click, and while the burner is whooshing, and the propex lights in that condition, at sea level

the light goes on only very briefly at altitude, and though I hear the ignition click, and the whoosh of the burner, the LED does not stay lit at altitude, when the propex fails to light

> I assume you have already used a bit of compressed air and blown the heater out somewhat, I know you travel a lot in dusty conditions so inhaling dust could always be a possibility.

NO, I have not blown the lines out, but, I now live on pavement in California, not dirt like before in New Mexico.

And, the Propex ignites on first attempt at sea level. I have relit it 4 times today, and it lit on first attempt every time.

Yesterday at Squaw, 6000 ft altitude, it never lit on first attempt, it sometimes lit on second attempt.

By attempt, I mean, the propex circutry makes 2 attempts before giving the 2 flash error code, which afaik, is a propane error, but I have plenty of propane, my stove lights. And my regulator and propane tanks were replaced with new within the past 18 months, so unlikely to be a bad regulator..

I surmise a remote possibility that my Propex has an issue with cold temperatures, not sure though. At sea level it is also above 60F, whereas at Squaw temp was above 40F when it lit, and below 30F when it failed repeatedly.

of course it sucks to have a heater that only works when its warm..

what do I check/rant about next? I suppose its possible that my propane line is kinked a bit, and when cold the opening closes down enough to interfere with the propane flow.. pretty remote possibility, but, its a thought..

any other suggestions most welcome

its only a rant if Im not open to change.. right .. I WANT change.

and ps, please vote in the poll if you have not already, so far only 5 of 9 votes are for units that work every time. Lets figure out how to make it 9 out of 9 work every time.

[Californio]

The Propex will run on VERY low voltage. I've had mine work when the battery light is on red for a long time and IIRC that means less than 10.5 volts. Low voltage wouldn't explain why it doesn't work at altitude, either.

[FNGRUVN]

If it was the battery, wouldn't you get a low voltage error code. Three flashes of the led, I think.
_________________
"Democracy is two wolves and a lamb voting on what to have for lunch. Liberty is a well-armed lamb contesting the vote." - Benjamin Franklin

[Jon_slider]

Im beginning to think the problem may be my Odyssey 1200 battery.

To answer Karl, the red LED on the circuit board lights very briefly. It does not stay lit. Yes I get clicks, and yes the heater attempts to light, twice per cycle, then it goes to the 2 red flashes on the thermostat.

What battery are others using for an Aux battery under the driver seat. Im beginning to think my Odyssey is never fully charging.

The reason I suspect the battery now, is that the heater did light when I first got to squaw, after driving the van for 5 hours. But it would not light in the morning, after the van was parked overnight.

I then moved the van to a different spot, which meant running the engine, and after that the propex lit, once. It did not light a couple hours later.

So, moral of the story, as with many things Vanagon, the problem may not be the Propex at all, it may be my house battery voltage?

anyway, the snow was hard, my boots too tight, and I went home early.

but the scenery was beautiful, and my down comforter kept me warm despite the Propex failure.

thanks for the offers to help, will let you know if changing batteries solves the problem.

Jonathan
ps, Im at sea level this morning, the Propex lit on the first try, even after being parked overnight and not running the motor. Im on my way to Van-Cafe to test the battery anyway. Will post any new info.

[FNGRUVN]

Is the combustion chamber getting enough air? At altitude you need more air and less fuel. Just wondering if the combustion intake pipe is restricted or routed funny.

I have mine installed under the rear seat. The intake tube is about 8-10" long and the exhaust is routed out of the jack point.

I've used mine at 10,500' with no problems. I hope you get this figured out. These are awesome heaters.
_________________
"Democracy is two wolves and a lamb voting on what to have for lunch. Liberty is a well-armed lamb contesting the vote." - Benjamin Franklin

[Outback Kampers]

Jon, I need more information: remove the small cover plate and report back on how the heater behaves when it starts:
The red LED on the circuit board should flash once when the switch is turned on. Then, you should hear one audible click (gas valve opening) followed by a series lighter clicks (ignitor firing). Then the LED should come on and stay on. Please verify at what stage the heater differs from the above. Then I may be of more help in fixing what ails it. I assume you have already used a bit of compressed air and blown the heater out somewhat, I know you travel a lot in dusty conditions so inhaling dust could always be a possibility.

There are a LOT of things I am sick of, but I try to fix them. Rants rarely fix anything in my experience.

By the way, RV shops have little idea of the workings of the Propex, being vastly different from the RV heaters. Seems more productive to go to the guy that knows em best.
_________________
Karl Mullendore
1990 Syncro 16" sunroof Reimo highroof conversion
1990 Westy Multivan 112i automatic
1992 LT31 Karmann Distance Wide 'La Tortuga'
2014 Touareg X TDI

[wildenbeast]

Mine has always worked well at altitude; I have used it at 5500' where I live all the way to 10,500'. Would you be able to bring it to a local RV repair shop? They have helped me with things like this in the past. Bringing it to a local shop, you can know that they will already be at a similar altitude.
_________________
- Bill, '93 Eurovan Syncro Weekender (2.5 manual ACU)