Kitchen Sink On, No Heater Firing. Rest of House Fixtures Fine.

Discussion in 'Tankless Water Heater Forum' started by MichaelBukay, Jun 19, 2013.

  1. MichaelBukay

    MichaelBukay Plumber

    Messages:
    50
    Location:
    San Diego, California
    So I have sort of an odd problem. This house I was working on doesn't get hot water in the kitchen. The tankless is a Noritz N069-M. Every other fixture in the house, when the hot water draws, fires the heater. Yet the kitchen does not. I didn't install the heater, or any of the piping, I was just asked to take a look at the problem. I'm at a loss. The kitchen is about 40' from the heater, and the bathrooms are within 5'-10'.
  2. Dana

    Dana In the trades

    Messages:
    2,783
    Location:
    01609
    What's the flow rate like at the kitchen, and is it a mixer valve (likely)? Did it ever work properly at the kitchen sink?

    There is a min-flow requirement to get the tankless to light-off- cracking it open at a dribble won't cut it, even if once it lights it can be taken down to a fairly low flow without flaming out. Min-flow on the N069-M is 0.5 gpm- below that it can't light, or will turn off. If the mixer at the kitchen is defective and only delivering cold or not enough flow on the hot side, that could cause the symptom.

    Turn off the shutoff valve to cold side of the mixer, see if that affects the total flow when the mixer handle swung all the way to "hot", &/or the ignition issue.

Share This Page