Date:         Thu, 13 Jul 2000 09:33:23 -0700
Reply-To:     Brent Christensen <brent@vanagon.com>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Brent Christensen <brent@vanagon.com>
Subject:      Re: FW: lighting fridge on propane
Content-Type: text/plain; charset="iso-8859-1"

The best analogy I can think of (and this is the approach I take) is to
treat it like a carbeurated car that floods easily.  (same principal more or
less).  The pilot button is the accellerator pump, and the push button is
the ignition.  The fridge's air pump is like cranking the engine without
adding fuel (i..e the pistons are essentially air pumps that pull air/fuel
mixture into the cylinders).

A car will flood if you pump the accellerator too many times before starting
when it is cold.  In order to start a flooded car, you have two choices:
wait for the excess fuel to evaporate/clear the combustion chambers, or
crank the engine with the throttle at WOT (without pumping) so that the
cylinders will pull fresh air in (plus a little fuel due to venturi effect).
This normalizes the air/fuel ratio, which then becomes combustible again.

Whew - long winded explanation to a simple problem - air/fuel ratio.

Brent Christensen
'89 GL Syncro Westy "Klaus"
Santa Barbara, CA

----- Original Message -----
From: "Bill Davidson" <wdavidson@thegrid.net>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Thursday, July 13, 2000 8:49 AM
Subject: Re: FW: lighting fridge on propane


> Equally important as where the gas/thermostat knob is turned is the length
> of time you hold in the button until you click the sparker (piezo)... From
> the time you push in the button gas is starting to fill the combustion
> chamber. The longer the time until you spark the pieze, the more gas in
the
> chamber... and the less air. If there is the gas/air mixture is too much
gas
> and not enough air you will get an explosion (loud pop) but there is no
air
> left to keep the flame going. (Also, working the pump faster/longer and/or
> running the fridge on 110 or 12 v for a time before attempting to light on
> propane will have some positive effect on available air for combustion.)
>
> So it is more complex than where the gas/thermostat knob is turned. This
> timing factor (how long button is held in) explains why some have success

> with the know turned all the way down and others have success with the
knob
> turned all the way up.
>
> Bill
> ----- Original Message -----
> From: "Doug Alcock" <dgalcock@hewitt.com>
> To: <vanagon@GERRY.VANAGON.COM>
> Sent: Thursday, July 13, 2000 8:19 AM
> Subject: Re: FW: lighting fridge on propane
>
>
> >
> >
> > Hmmmmm.......my fridge lights reliably with the thermostat up all the
way
> and
> > the 'pop'
> > I get when I hit the igniter is a blessed and joyful sound that tells me
> my
> > fridge just lit. I'm keeping
> > my fridge lighting ritual as is and not messing with my mojo now that
I've
> > finally got it working.
> > Bet I'm not the only one thinking this way.............though I'll save
> the info
> > for a rainy day.
> >
>
>
> --------------------------------------------------------------------------
--
> ----
>
>
>
> Recently had the same instances of 'mini-explosions'.  I took it to a
camper
> dealer who called Dometic.  They now suggest turning off the thermostat
> entirely before lighting the fridge and waiting at least 15 minutes before
> turning the thermostat to cool.  This procedure works great on my 89
Westy.
> The pre-cooling on electric was also suggested.
>
> M Williams
>
> In a message dated 7/13/00 8:13:32, TCarrington@ReliTech.com writes:
>
> << -----Original Message-----
>
> From: brent@vanagon.com [mailto:brent@vanagon.com]
>
> Sent: Wednesday, July 12, 2000 1:57 AM
>
> To: Fred Brittain; vanagon@GERRY.VANAGON.COM
>
> Subject: RE: lighting fridge on propane
>
>
> Though I am not an expert, I don't think the knob controls the volume of
gas
>
> delivered - it is more of a thermostat that controls a cut-off point for
>
> temperature.  Given this, it should make no difference vis-à-vis the
>
> "popping" syndrome.  I think this is more due to environmental conditions
>
> and bad mojo.  Please don't underestimate the power of mojo in getting the
>
> fridge lit.  (precious little has been written on the subject)
>
>
> :-)
>
>
> Brent Christensen
>
> '89 GL Syncro Westy "Klaus"
>
> Santa Barbara, CA
>
>
> -----Original Message-----
>
> From: Vanagon Mailing List [mailto:vanagon@GERRY.VANAGON.COM]On Behalf
>
> Of Fred Brittain
>
> Sent: Tuesday, July 11, 2000 1:37 PM
>
> To: vanagon@GERRY.VANAGON.COM
>
> Subject: lighting fridge on propane
>
>
>
> Just read the vanagon.com article about lighting the fridge. Does
>
> anyone remember when a listee contacted Dometic about this subject and
>
> posted their reply to the list?
>
>
> The Dometic rep said to turn the temp knob to a very low position when
>
> lighting. I've done exactly that since I read the post and have had no
>
> more trouble lighting up. When I turned the knob all the way to cold,
>
> it wouldn't light but would ignite what sounded like mini-explosions
>
> every few seconds. Same principle as trying to light a propane torch
>
> turned up all the way. It simply does not react to a spark igniter or
>
> blows out a match.
>
>
> regards,
>
>
> Fred (former semi-active listee)
>
> 89 Westy