Forum Discussion

rerod's avatar
rerod
Explorer
May 25, 2016

Water heater gas valve knob needs pushed down for ON?

I had problems keeping the water heater lit last time we took the toyhauler out. I had to hold the knob down in the pilot position forever before I got it lit. Fine, its lit but looks small. So I try and turn the knob to ON and the knob stops just before the mark, but the main burner is on and heating.. Fine. 10 minutes later both the main burner and pilot are off so I blamed the wind from the Colorado prairie.

I got the pilot lit faster this time and turned the knob to ON again and again noticed the line's don't match up so I mess with the knob and find out I need to depress the knob a little for it to turn completely where the lines match up..

Is this normal? I'm used to depressing the knob for pilot lighting..

But is it normal to have to depress the knob to turn the gas valve to ON?

Thanks!
  • rerod's avatar
    rerod
    Explorer
    May 25, 2016
    Old-Biscuit wrote:


    Does main flame work......come on/off via thermostat and pilot stays on (when you push/turn knob to ON)???
    If so......I wouldn't worry about it

    ON EDIT:

    LOVE the V-MAX
    I had a 1985 and a 1990 (drunk wiped out 1985)


    Yes. I just lit the pilot, released the knob and turned it to ON and watched it cycle as I used hot water.. But no wind in my back yard.

    But I'm still not used to pushing the knob down again to turn to the ON position, and worried the gas valve is failing.
    I would have to turn around and go back home without hot water.

    Thanks. I have two 1985 Vmax's.
  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    May 25, 2016
    Normally you turn knob to 'pilot' position then press & hold it down until pilot lights and has burned for 30 seconds or longer (long enough to heat thermocouple up) then you 'release' knob and turn to ON

    Pressing knob down bypasses safety device allowing gas to flow to pilot
    AFTER thermocouple is heated........a millivolt signal is generated and energizes a magnet holding it OPEN (safety device) so holding knob down is no longer needed.

    IF you 'release' knob while in pilot position is pilot flame staying lit?

    If not------
    weak pilot flame---should be steady blue flame with tingles of orange at tip.
    pilot flame should impinge/heat thermocouple
    (correct propane system pressure/clean pilot orifice)
    bad thermocouple/loose thermocouple connection at gas control---clean/tight connection or replace thermocouple

    OR bad ECO or magnet -----have to replace gas control

    If pilot is staying lit.....
    knob is worn/gouged/damaged

    Does main flame work......come on/off via thermostat and pilot stays on (when you push/turn knob to ON)???
    If so......I wouldn't worry about it






    ON EDIT:

    LOVE the V-MAX
    I had a 1985 and a 1990 (drunk wiped out 1985)

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