on-board/extend-a-stay switchover procedure (RV)

Discussion in 'Motorhome Chat' started by Bryan, Nov 17, 2011.

  1. Bryan

    Bryan Read Only Funster

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    Now as I understand it, the extend-a-stay plumbing into the on-board gas system is incredibly simple.

    There is a 't' piece between the on-board gas tank's valve and the on-board regulator.

    You attach a gas bottle to this 't' piece.

    When you want to use the gas bottle, it's valve is opn and the on-board valve is shut.

    To use the on-board gas the bottle's valve is shut and the on-board one is open.

    Now it seems to me that the PROCEDURE for switching either way should not matter (which valve sequence to use). A little air might get in somewhere along the line (when changing to on-board gas whilst you change bottles for exampl) but this will be expelled and all will work in a few seconds.


    Last night I had an issue...

    I ran out of bottles gas whilst cooking. No problem, I thought, popped out of the van and opened the on-board valve, closed the bottles valve.

    No gas at the cooker.

    If I left the hob switched off for a minute or two, the gas would light but with a few seconds, die and go out. No gas.

    (On-board gas is 3/4 full)

    Tried several times, several ways - no joy. Left hob switch on but no sound of air/gas.

    Tried fridge on gas but no joy.

    Had to borrow a new bottle and revert to bottled gas for the night.

    Just tried the following this morning:

    Checked all working on bottle - all ok.
    Opened on-board valve (bottle still connected and open) - all ok
    Closed bottle valve (still connected) - all ok
    Removed bottle - all ok

    Now that plainly makes no sense.

    Anyone offer an idea as to what went wrong last night?


    I don't think it was air in the line as I left the hob switched on and heard no air/gas coming out. Tried lighting but it would not light. Switched hob off for a minute and it then lit but died within seconds - as if some gas had built up pressure.

    Bryan
     
  2. Snowbird

    Snowbird Funster Life Member

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    Hi Brian, The extenda stay pipe should be removed from the extenda stay when running from the onboard tank. The reason behind this is the extenda stay screws into the T piece and partialy blocks the tank pipe. Remove the pipe and put the cap on and all should be well.
     
  3. Bryan

    Bryan Read Only Funster

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    I understand and could accept that but...this morning

    Contradicts that.

    I'm very confused...
     
  4. Sundowners

    Sundowners Funster Life Member

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    Hi Bryan
    Dave could be correct with his theory:thumb:---------BUT------------all? RVs have a safety valve to cut the supply in the event of a massive gas leak--------turn ALL gas appliances off, then open the gas valve slowly-----wait a few seconds---this equalizes the gas system and allows the safety valve to open----------try this method and see if it improves things?????!!!!!!--------just my opinion:BigGrin:
    I don't know---but I wouldn't expect the extenda-stay to make a difference
    Nigel & Pamala
     
  5. Snowbird

    Snowbird Funster Life Member

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    If you gas sniffer detected gas whilst you were playing with it, it would shut the gas valve down. Mine does and if I open the door and let the smell of gas go all's well afterwards. That's the only explanation I can give.
     
  6. Bryan

    Bryan Read Only Funster

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    I wonder if having both valves open when the gas bottle was empty caused the gas pressure to drop sufficiently to make the safety valve activate?

    Putting the new bottle on may have equalised the pressure hence why I can now get it working no matter what I do?

    I still have the empty bottle so I may try and re-create the problem and try your 'fix' to see if it works...

    (I reserve the right to be completely wrong in anything I say :thumb:)
     
  7. JJ

    JJ Funster

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    IMHO, the Gas Fitter Fairies fixed it whilst you slept the sleep of the innocent at night...

    JJ :Cool:
     
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  8. Bryan

    Bryan Read Only Funster

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    Right, problem re-created.

    (I hope you all appreciate my efforts...do you have any idea how hot it became putting three gas rings on whilst it is v.hot here in sunny Spain? :Cool:)

    Right, started with a working on-board supply.
    Added empty bottle via extend-a-stay and opened the valve (on-board still open)
    My gas rings slowly died. (indicating that a safety valve may well have kicked in.
    Closed bottle's valve - no different
    Closed on-board valve and waited 2 minutes
    Cracked open on-board valve and heard gas 'fill the pipe' - took 0.5 seconds
    Fully opened on-board valve quickly
    Disconnected extend-a-stay FROM THE BOTTLE (still connected to RV)
    Checked hob - all okay.

    So it does seem that opening the on-board valve whilst still connected to an open but empty bottle caused this problem.

    Next time I empty a bottle I will (if I remember) do the following:

    Close the bottle valve.
    Crack the on-board valve - wait 2 seconds
    Open the on-board valve fully

    I would of course do this now but did you get the hint about how hot it is?


    Bryan (now fully accredited gas engineer...and not a relay in sight)
     
  9. Snowbird

    Snowbird Funster Life Member

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    Next time listen to what I tell ya :Rofl1:
     
  10. aba

    aba

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    seems to me that you could have been in effect trying to refill the empty bottle from your on board tank and it didn't like it.

    and not an ebay refil adapter in sight :Rofl1::Rofl1::Rofl1::Rofl1:
     
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