Date: Sat, 18 Dec 2004 14:08:32 -0700
Reply-To: Richard A Jones <jones@COLORADO.EDU>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Richard A Jones <jones@COLORADO.EDU>
Subject: Re: [Syncro] 2nd propane tank/heater-Dual tank instalation!
In-Reply-To: <000001c4e314$b8f7b8b0$6400a8c0@masterpc>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Dennis:
This method is neither wrong nor dangerous. I think your
analysis of it is wrong. I checked before I did it and had
my local RV expert help. Connecting the low pressure outlet
side of two regulators is also a practice in various industrial
and home setups. It is safe.
If both tanks are open, the regulator with the higher pressure
setting will be emptied first, then when its output pressure
drops to equal the setting of the other, the second tank will
start to empty. Having check valves is used in some setups
where one wants to disconnect the empty tank from the regulator
to refill without shutting off the other tank in use.
A Westy tank is refilled without touching the regulator.
A regulator will not "vent" propane--unless it has gone bad.
The vent (or two vents on the Westy regulators) are primarily
to allow the diaphragm to operate. The vent is "behind" the
diaphragm--that is on the opposite side from the propane--so
the diaphragm isn't pushing against a sealed compartment.
Only if it ruptures does it vent propane--this is regulator
failure.
The regulator you favor works well with a pair of RV DOT
tanks, connected with high-pressure pigtails to the regulator.
The regulator is separated from the tank like most DOT setups.
These are not mounted underneath RVs since the DOT are
vertical tanks.
The Westy is wisely designed with the regulator connected to
the POL valve and protected by a mud flap and the skid plate.
Why defeat this and run a high pressure line across underneath?
I've seen oil filters punctured by rocks; I wouldn't want a
high pressure line under my syncro. And how to mount this
regulator safely protected since it is a vertical setup? The
RVparts web site states that the regular horizontal, side-vent
regulator is "mandatory for use on horizontal tanks"--the
Westy setup exactly.
Lastly, remember that the purpose of two tanks is to not run
out of propane, so only one tank is open at a time. I note
when I have to switch tanks to refill the empty one.
Connecting the low pressure output side of two regulators is
easy and achieves the desired result very simply--and it
is safe.
Richard A Jones
Boulder, Colorado
> The method you describe for connecting two tanks together is wrong and
> extremely dangerous. Propane regulators should never have the outlets
> tee'd together unless there are check valves on both sides. Propane
> regulators control pressure using a spring loaded diaphragm and spool.
> When outlet pressure is sufficient, it closes the source. If pressure
> continues to increase due to expansion or failure to close or what have
> you, it vents through that screened outlet. Now if one regulator adjusts
> to 11" WC and the other for some reason goes for 11.5" WC, the lower
> pressure unit will continuously vent. This is why the regulators are
> always installed outside or the vent gets hard piped outside.
>
> The best way to installed dual tanks is to install a regulator designed
> for the task or to use an isolating tee for the input. This auto
> changeover is my favorite due to price, convenience, and built in
> isolation.
> http://www.rvpartscenter.com/ProductDetail.asp?ProductID=34672&StoreID=1
> 2&DepartmentID=37&CategoryID=216&BasketID=
>
> Dennis
>
> -----Original Message-----
> From: Richard A Jones [mailto:jones@colorado.edu]
> Sent: Wednesday, December 15, 2004 12:01 PM
> To: saltss@copper.net
> Cc: Syncro@yahoogroups.com
> Subject: [Syncro] 2nd propane tank/heater
>
>
> Kelly:
>
> For a description of mine, see:
> http://hometown.aol.com/realsf/howtopage2.html
>
> This is an old page, with one typo:
>
>>> a red-hot day by someone who had never seen an autostop valve--and did
>
> care! . Won't have
> That should be "didn't care" and any references to my address or
> webpage should be jones.colorado.edu, not coyote.colorado.edu
>
> I have a Carver heater under the rear seat--exactly like the Sittser
> description:
> http://www.sittser.com/
>
> The Carver isn't available anymore, but Propex is (back) in
> business and Karl Mullendore imports them:
> <thewestyman@mindspring.com>
>
>
> Richard A Jones
> Boulder, Colorado
