New Propex 2000 questions

[markf1]

[markf1]

Another round of propex testing this morning. Unfortunately, the propex is still having troubles with start up.

Ambient air temp 30F. Turned on propane, lit both burners on stove. Followed instructions for starting propex. Start cycle begins, green light turns on propex tries to fire up for @5 seconds, green light turns off, fan continues to run for @25sec., cycle repeats @ 15 times. Green light stays on longer and propex seems to be running for @ 20 sec., green light goes off, fan continues to run for @25secs, Green light turns on again, propex fires up and now stays on and runs as should indefinitely. Measured air temp at out put vent @180F.

I guess I'm going to set up one of those water column manometers as the nest step. I'll report back once that has been accomplished.

A bunch of photos showing the existing conditions the van is living in, the regulator, and other install photos. I do question the old two line propane fitting that I have attached to the regulator as possible source of trouble. It's marked in red in one of the photos below.

_________________
1986 Westfalia Syncro
2.1 L Waterboxer
Some Westy supported adventure photos:
https://www.openrangeimaging.com/adventure.html

[markf1]

One question about the manometer photos above. The spacing of the lines is labeled as 1/2" increments but the lines appear to drawn and spaced in 1" increments?
_________________
1986 Westfalia Syncro
2.1 L Waterboxer
Some Westy supported adventure photos:
https://www.openrangeimaging.com/adventure.html

[jimf909]

Yes, the lines are at 1/2" increments. The 1" of pressure comes from 1/2" down on the right side of the "U" and 1/2" up on the left side, i.e. we're measuring the difference between the water level on each side of the U.

Here's the link Karl posted where I learned everything manometer...

https://rverscorner.com/manometer.html
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- Jim

[markf1]

We have this regulator. It came attached to the new propane tank we got from GoWesty in 2014.

https://www.gowesty.com/product/lp-tank/2448/lpg-gas-regulator-2-stage-?v=

Assuming it needs to be adjusted - does anyone know how that would be done? I cannot find any manual or any info about adjusting it.

I'm thinking I would need to turn the gray colored "nut" on the second stage of the regulator. Seen to the right of my red markup arrow in the photo above?

Thanks!
_________________
1986 Westfalia Syncro
2.1 L Waterboxer
Some Westy supported adventure photos:
https://www.openrangeimaging.com/adventure.html

[markf1]

[jimf909]

[markf1]

I made a manometer and tested the water column. Admittedly not as nice of a manometer as shown in the previous post. I used a scrap piece of styrofoam and the edge I put a framing square on to draw the lines was a bit soft and uneven so my lines, mainly the zero line is a little slanted. Still I think it gives a decent picture of the water column.

Without any appliances running reading 12. Turn on propex and it drops to about 11.5.

This time when I started the Propex. Ambient temp @38F, maybe a bit warmer inside the van. Did NOT start the stove first. Propex fired up and ran on second start cycle.

Water column test makes it appear that regulator pressure is OK. It seem that cold temps are affecting the propex ability to start correctly.

Any ideas what could be causing this?

_________________
1986 Westfalia Syncro
2.1 L Waterboxer
Some Westy supported adventure photos:
https://www.openrangeimaging.com/adventure.html

[jberger]

I didn’t read every post.. but did you try removing the wire “guards” from your vent lines? The only times my propex has failed to light was due to very small reductions in flow from snow build up or even spider webs. A quick blast of compressed air from either end cleared it up. I’m wondering if your screens are the culprit.

J

[markf1]

hmmm- it's a pretty much brand new install last fall.. and we had the problem then. By vent lines do you mean the black combustion air intake tube that is shown under the van in photo above? hard to imagine the hardware cloth mouse/screen i have over that is causing this trouble.

It seems to start fine except in cold <32F. just started ok at 38F
_________________
1986 Westfalia Syncro
2.1 L Waterboxer
Some Westy supported adventure photos:
https://www.openrangeimaging.com/adventure.html

[jberger]

[markf1]

OK, I've tried everything else I can think of so I'll give that a try in the morning and report back. thanks!
_________________
1986 Westfalia Syncro
2.1 L Waterboxer
Some Westy supported adventure photos:
https://www.openrangeimaging.com/adventure.html

[markf1]

Removed the 1/4” hardware cloth bug/mice screen I had placed at the ends of the air intake and exhaust tubes.

Ambient air temp @35F

Propex would not start. Ran thru 6 start cycles without starting before I turned it off. Lit both stove burners. Propex started on first try.

In a post above you can see at colder temp, 30F, the propex still had trouble starting even with the stove burners lit.

Something about cold temps is causing this.

Also notice that when I start the propex I have the tstat temp control all the way anti clockwise at it’s lowest/coldest temp setting. I turn the fan switch to the light position and the propex begins it start cycle. No need to advance the temp control to initiate the start up. Not sure if this means anything, probably not. Just putting it out there in case.
_________________
1986 Westfalia Syncro
2.1 L Waterboxer
Some Westy supported adventure photos:
https://www.openrangeimaging.com/adventure.html

[MarkWard]

A combustion engine requires a richer mixture start on a colder day. Isn't the Propex a type of combustion engine?

What would be interesting would be to see if a proper camper kitchen holds any kind of residual pressure when the stove and fridge are off. I'd expect with the valve open on the tank to have constant pressure at both outlets.

Lighting your stove would have the affect of filling the propane system, which shouldn't be required. Only when you've had the system open or the tank valve closed for a long period of time, the residual pressure might bleed off. Interesting problem.
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☮️

[markf1]

More frustrating than interesting I’m afraid.

I wonder if when it tries to start, and the green light comes on for 5-10 seconds, if each time it does that it warms something up a bit. After enough attempts, whatever it is finally gets warm enough and the she finally kicks on and stays on.

Is there any kind of thermocouple or some such thing like getting a plot light warm enough before letting go of the button?
_________________
1986 Westfalia Syncro
2.1 L Waterboxer
Some Westy supported adventure photos:
https://www.openrangeimaging.com/adventure.html

[westyventures]

If it ignites and blows out (green light on, the off), it does still sound like fuel delivery is a little sluggish. There's no reason to test at the stove. A better test point would be to disconnect the heater line and connect the gauge there, then run both stove burners full-bore. That would tell whether the regulator was really doing its job.
About the Cavagna regulator: the atmospheric vent is tiny compared to every other regulator on the market, and has a super-fine screen that can easily clog or freeze over. Any amount of moisture - or contamination - in the propane tank would exacerbate the inherent flaws of this regulator. The adjustment on it is backwards from all others, it screws out / CCW to raise the pressure.
The only other thing I can think of is slow flame sensing, but almost unheard of on newest units. Flame sensing is made through the ignitor tip, so if it ignites properly then the tip is properly located to also sense flame.
Is there any chance of dust or debris being introduced into the heater's gas inlet during installation? Was the line blown through before connecting to the heater?

[markf1]

Hi Karl and thanks for your reply.

I guess of course there is always a "chance" of dust or something getting into a copper tube line when installing and routing underneath 1986 vehicle.

No I did not blow out the propane tubing before attaching to the heater.

I'm getting the idea that the only thing I can do at this point is to replace the regulator and just hope that helps. That is not insurmountable but it also is no easy task to take apart the fittings and put in the new regulator and hope it all re-connects the same without having to redo any tubing or flare fittings or etc.

I'm not going to attempt that this Feb-March outside in the snow where it is. If that's the only thing we can do it will have to wait till after our spring trip with the van. We'll just have to endure the 20+ start cycles necessary to get the propex running to warm up the van enough to hang out for an hour or two on cold morn-eve's. Disappointing and frustrating after spending $800 on the propex, $300 on the acc battery needed and days spent to install the system.
_________________
1986 Westfalia Syncro
2.1 L Waterboxer
Some Westy supported adventure photos:
https://www.openrangeimaging.com/adventure.html

[westyventures]

It seems more and more people tend to blame the '$800 heater' as the problem each and every time, regardless of what other external issues might exist. My advice to rule out external issues seems to be too much effort. I've been doing this seventeen years. I've thrown more of these Cavagna regulators into the trash can than any other brand. I've also seen contaminated tanks that will freeze up or slow down vapor delivery even on good regulators, the tiny Cavagna is even more susceptible. That the heater runs when warmer points to a fuel delivery issue. I'd wager that on a test bench the problem could not be recreated. If you had another known good portable tank and regulator that could be connected temporarily that too could help rule out the above.

[markf1]

I'm not "blaming the heater" but we have a very new tank, valve, regulator and LiFePo4 accessory battery. I tested the delivery of the regulator by building a manometer.

I have made every effort I can to rule out external issues.

I respect that you have been doing this for 17 years and I have never dealt with one of these until now. From what I understand you have never seen a problem with the heater itself and it's always and without exception some problem outside of the heater.

Once things warm up, and we don't need to use the heater, I will buy and install a new regulator and hope that may help.

Regardless of what the problem is, it does not relieve the frustration and disappointment of buying the best and very carefully installing it, running all kinds of trouble shooting and still not having it work correctly. That's not blaming the $800 heater, that's just reality.
_________________
1986 Westfalia Syncro
2.1 L Waterboxer
Some Westy supported adventure photos:
https://www.openrangeimaging.com/adventure.html

[westyventures]

Since the stove is not the appliance with the issue, a flow and pressure test at that connection isn't the best way to diagnose if there is / isn't a flow issue to the heater. Connect the gauge to the heater line at the heater after disconnecting the line there. Then run both stove burners and carefully watch the gauge for deviation from 11-12". The best scenario to reveal if there is a contamination issue is to test at a colder temp.

I did not state there are never any problems with any heaters - only that the symptoms are those of a supply problem since the reliability seems to be far better after lighting the stove. If it were here I would connect my portable tank and regulator to the heater and if it started well then would look through the supply system. I wish I could teleport myself and equipment remotely but that technology isn't available yet.
The other option is to send the unit to me for testing/service - but that would need to be done immediately as things will be 'changing' very soon on where to send.