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SuperRR's avatar
SuperRR
Explorer
Jun 16, 2014

Old water heater question

We just picked up a 1978 Prowler 28' trailer. I cleaned out the burner tubes in the American Appliance Mfg water heater. It has a unitrol setup on it. I was able to light the pilot easily and the main burner had no trouble coming on. It clicks off at temperature and clicks on when its supposed to. I turned the main knob to 'OFF' and I could hear/smell propane for about 30 seconds after the pilot went out. Is this normal? We're living in the trailer full-time to keep cost of living down so we can pay off past debts, so its kind of an important appliance to me.

3 Replies

  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    Jun 16, 2014
    Gas valve is leaking into combustion/exhaust chamber.
    With pilot flame still on the small amount of propane until gas valve fully closes will be burned.

    With pilot off.......it will just leak into chamber and then dissipate

    Just be careful when you go to light pilot.......could go whoosh, shoot a ball of fire out exhaust/blow back out combustion chamber and singe your eyebrows
  • SuperRR's avatar
    SuperRR
    Explorer
    Jun 16, 2014
    Thanks. I'll look into a replacement. Aside from that, it works well. Do you suppose it's safe to use in the mean time?
  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    Jun 16, 2014
    LP pressure at gas valve is roughly 0.4 psi (11" WC) a very low pressure.

    Your gas control valve should fully close when you turn it OFF.......not slowly close.
    No adjustments/fixes except replacement

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