RV Doctor – Is My LP Regulator Installed Correctly?

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June 4, 2009

Dear RV Doc,
The first stage regulator diaphragm on my motorhome failed and was leaking LP gas out the vent hole. I had my service center replace it but I think they may have installed the wrong regulator.

The work order listed the regulator as a 2-stage regulator VERT. I asked what the VERT meant and the tech said not to worry, that the regulator was installed correctly. Since he didn’t install a regulator cover I have some reason to suspect his competence. However, when I look up the regulator on the Marshall Brass Web site (the manufacturer) they show pictures of two regulator styles that are identical except for the vent discharge on the second stage regulator. I didn’t find enough information to allow me to decide which regulator model should have been installed.

The motorhome has a horizontal tank and the regulator is also horizontal but on this new regulator the vent from the second stage regulator section is facing forward. I’m guessing that it should be pointed down. I’m trying to get information from other sources, but I’m feeling it may be difficult to get to anyone who knows about this issue. – Mike Rehmus, (Vallejo, CA)


Mike, you are very astute and it’s a good thing. The RV Standards state that the vent portion of the LP regulator must be oriented in a downward position, within 45-degrees of vertical. And indeed it should be covered. Marshall Brass and others specifically manufacture LP regulators in various configurations to accommodate both horizontal mounting and vertical mounting.

Your technician obviously installed a vertical regulator in a horizontal position thereby negating the “within 45-degrees of vertical” orientation of the vent. The reason for the standard is so that mud, snow, road debris, etc., will not have the ability to clog that secondary vent opening. It’s a safety issue.

Now if that same regulator is mounted in a plastic cover, chances are good the vent would never become clogged with mud or freezing particles of ice and snow, and the regulator would still probably function correctly. But it simply is not the correct part for your installation.

I sensed a bit of disingenuous misinformation in your technician’s response, especially when you specifically asked what VERT meant. I’d look around for a more competent technician. At the very least, the Service Manager of that shop needs to be informed of your situation.

(Please feel free to comment, however, please also note that due to the volume of communications I receive from multiple channels I cannot guarantee a personal response in every instance. However, questions of an overall general interest may be considered and published in an upcoming RV Doctor column.)

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  2. Gail

    I have a Kohler 4.5 ckm 22rv generator and I have found that is states 120 volts on the side of the unit, yet I have been told that it can be wired to provide 240 volts.
    It has two 30 amp breakers built into it, and I would like to know, can this unit be wired to provide 240 volts, and if this unit is wired to provide 240 volts, will it be a 30 amp circuit?

  3. Bill Weber

    I have a 4.5ckm 22rv LP gas gen in my motor home. It acts like its out of fuel[slow to start, won’t keep running, does a little backfiring at times.] the engine coil has both plug wires in one coil. [ a weak coil problem ]? The background to this problem was this summer when the ac would cycle to come back on the gen would stumble and sometimes quit. Thanks for your help. Bill

  4. Yes gentlemen, we do read these comments, but with so many posts and comments, it takes us a while to get to them all. 🙂

    In this particular instance my assumption is the error was a simple cut and paste error. Since Mr. Bunzer uses the same basic layout for each of his posts, like many authors, he likely copies a current post, then edits it, pasting in the new information. The post has now been fixed.

    Thanks for keeping us on our toes!

  5. Jay

    Maybe it just stock “computer” answer-not a real person…lol

  6. Bill

    The first paragraph is from the answer to the question from the guy who had oil in his propane lines. The rest of the paragraphs appear to be the answer to this question.

    One would think they would fix this after two comments about it. We’ll have to see if anyone from the website reads these comments.