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Takagi Tankless gets hot and sometimes not

BigTex61 Member Posts: 1
Looking for info. Our 3 year old Takagi has had an intermittent issue. Occasionally the water in a sink or shower will just not get hot. Flow is good but heater doesn't engage or something. I can hear the heater doing it's thing but nada. If I turn the sink or shower valve off and on 3 or 4 times, it will then (most of the time) get hot. Thoughts???


  • Have you cleaned the filter on the Takagi? It's on the inlet to the unit.

    You may also need to clean the shower head. Any debris or flow restrictors will reduce flow and could prevent the flow switch inside the Takagi from closing.
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
  • BigTex61
    BigTex61 Member Posts: 1
    Alan, yes cleaned filter and pumped vinegar through unit to clean like scale. Thanks!