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travistodd1's avatar
travistodd1
Explorer
May 14, 2014

Need some guidance before this weekends trip...

Hello all,

I have had some trouble with my old Lynx Prowler in the past but thought I had it all lined out. It has been in storage since January and I decided to take the family for a trip this weekend and in to the following week. I pulled it out and started checking things over and seem to have an issue similar to the last time (again which I thought was fixed).

The hot water heater will not light. It is a very basic Atwood unit that appears to only be able to be lit manually. I can get the pilot to light off but as it turn it to the "on" position it turns out the pilot and nothing kicks off like it should. I am having a similar issue with the furnace. I cant tell if the pilot is lighting or not though because of how bright it is and where the pilot is located..... it does not seem to be working at all though. The stove lights and seems to be working fine.

I checked the tanks (removed to fill just in case) and they seemed to be nearly full already....

Any suggestions? I hate to cancel the trip because of this...

Thanks
Travis
Seeking Advice
  • travistodd1's avatar
    travistodd1
    Explorer
    May 16, 2014
    Sorry it took so long to so long to get back to everyone. I was told by the wife that I had to go to a nephew's graduation yesterday.... of course that turned in to several other family events. Last night I cleaned the all the parts to no avail. I also replaced the thermocoupler and pilot assembly.... no luck with that either.... so $130 later for a new valve its working. I appreciate the guidance. I will also log everything in my book of mental notes for future reference. Old Biscuit, thanks for the offer and don't be afraid to shoot me an email if you need a hand.
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    May 14, 2014
    Three possible suspects.

    1: The pilot is not burning hot enough, Clean pilot orifice and adjust as per the owner's manual

    2: Control valve shot, There is a magnetic latching valve in the control valve body, Pushing the button you hold while lighting "Sets" this valve in the OPEN position, current from the next suspect holds (latches) it open.

    3a: Bad thermocouple flame sensor. This device develops about 0.480 volts DC when the pilot is burning properly... 3B: The connection between the thermocouple and the Control valve has tarnished and is presenting high resistance.

    4: You must hold the button for around 1 minute AFTER the pilot lights.
    (I'd add a bit to whatever it says on the label)

    This is identical (Even the control valve is basically identical) to the ones used in houses with gas water heaters, be they propane or natural gas. Control valve may be smaller in an RV is all. But operationally it is identical to a house unit.. I heated water with Gas for 30 years at home, and my parents before that.
  • beemerphile1's avatar
    beemerphile1
    Explorer
    May 14, 2014
    You may have a blocked orifice at the LPG cylinder due to excessive flow. If it senses too much flow it will almost completely block the orifice allowing only a tiny bit of LPG through.

    Turn the cylinder or cylinders off and wait a few minutes. Open the valve again but open gradually for the first bit. That should allow the LPG pressure to stabilize.

    Do you know that it is recommended that all RVs get a LPG leak down test annually? You should also put a manometer on it and check the pressure regulator. Read here;
    http://www.rverscorner.com/manometer.html
  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    May 14, 2014
    Pilot light is a simple system

    Is pilot flame strong steady flame that engulfs tip of thermocouple?

    Thermocouple needs to get HOT so milivot signal is sent to gas control to allow main gas to flow

    Thermocouple could be carboned up/dirty. Clean thermocouple with emery cloth.
    Thermocouple needs to have a tight connection at gas valve....if loose it doesn't allow circuit to be made. Check that nut at gas valve is tight........don't over tighten!!
    Thermocouple could be bad...replace

    Pilot flame not strong steady or doesn't engulf thermocouple...clean pilot orifice with alcohol

    A good cleaning of pilot/thermocouple assembly goes a long way in resolving lighting problems

    As for the furnace.....cleaning of burner assembly etc.

    PM me...I'm in Camp Verde Area also :B
  • travistodd1's avatar
    travistodd1
    Explorer
    May 14, 2014
    I am going to go buy a thermocoupler today and replace tomorrow. It looks like its pretty easy to do.... That being said I still need to figure out the furnace...

    Thanks
    Travis
  • DutchmenSport's avatar
    DutchmenSport
    Explorer
    May 14, 2014
    You may need help with this, but light the pilot (have someone else push the knob in). Before you turn the switch to "on", light a fire starter - cigarrette lighter or BBQ lighter, and hold it right by the pilot light (you now have 2 flames that become one. NOW have the second person turn the know to the on position. The flame should ignite in the water heater. The real test will be when the water heater reaches temperature, will the pilot stay lit?

    I had to do a variation of this process on my Dutchmen. But found the knob had a sweet spot where, when pushed, and then turned, it allowed gas to seep for the flame and the pilot.

    I think what's happening, when you flip the knob, there is one spot when the pilot light actually turns off (killing the flame), and then the heater won't ignite (no flame). It's such a minuscule spot on the switch, it's hard to catch it.

    Try it. If this does not work, maybe the thermocoupler needs replaced.

    Good luck!
  • travistodd1's avatar
    travistodd1
    Explorer
    May 14, 2014
    I let them run for several minutes while I messed with the camper. It acts for the world like its not even getting propane to the water heater or furnace. I cant get the pilot to stay on very long now either. I will go out easily. And like I said before, it will just go out the minute I try to turn to water heater to the on position.

    I have never used the water heater before but know and trust the guy that I got it from who advised that it operated perfectly. In January I had all kinds of trouble getting the furnace to work then all of a sudden it started working just fine.... Now ... nothing again. All 4 burners on the stove light and burn a nice clean blue flame.

    Propane tanks seem to be at the half full spot after checking them out a little further.
  • AirForceAngler's avatar
    AirForceAngler
    Explorer
    May 14, 2014
    Do you have a gas stove in the camper? If so, light all of the burners for a while to get rid of any air in the lines. After this, try your furnace and water heater again.

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