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Oklahoma_Dan's avatar
Oklahoma_Dan
Explorer
Aug 16, 2014

Need advice - Tankless Water Heater: No hot water

New Class C motor home and first experience with a Girard GSWH-1M Demand Tankless Water Heater. Turn hot water faucet on and you hear the blower inside the unit turn on for a short time. I don't hear the gas valve opening or the sparking sequence. It all worked fine for a few days then suddenly died. Pulled and looked at all the 15 amp 12 VDC fuses and they look fine. Other than the main panel do not see where any other fuses would be located. The water is on, plenty of LP gas. The Gas Modulator Dial (GMC)located inside RV is set properly up to 3/4. No RV dealers in Gunnison, CO where I am camped so for the time being I am trying to figure if there is a simple fix I have overlooked. It would be nice to have hot water again. Your input would be appreciated.
Class C
  • Oklahoma_Dan's avatar
    Oklahoma_Dan
    Explorer
    Aug 17, 2014
    dan-nickie had the advice to provide hot water. I was referred to a thread for this model of water heater. Over half-dozen people had the exact same problem. There is a cheap and tiny white little button in the external box which is to the back left side that you have to push. It is an over-heat switch. Why Girard says nothing about this button in their printed manual or website leaves me wondering why they do that. Thank you to those who have spent such detail (old-biscuit) and time helping me figure this out.
  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    Aug 17, 2014
    Is the LED on panel 'ON' or blinking? How many times?

    Open a faucet.....flow switch makes up. Circuit board goes thru a self check and then blower comes on. Sail switch has to CLOSE then DC power goes to gas valve and ignitor.

    If 'high limit switch' is OPEN (167*F) no power to circuit board for gas valve/ignition
    If 'ECO' is OPEN (131*F.....Closes 110*F) no power to circuit board for gas valve/ignition
    If 'Sail Switch' doesn't CLOSE no power to circuit board for gas valve/ignition

    LED ON or blinking.......??
    Error codes:
    •Steady On-Internal Control Fault (Circuit Board)
    •1 Flash-Air Fault (Sail Switch)
    •2 Flashes-Flame Detection Error (No main flame detected)
    •3 Flashes–Lockout (Ignition/main flame failure)
    •4 Intentionally ‘NA’–Reserved for Future Diagnostics
    •5 Flashes-Low voltage

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