Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Gas-fired hot water heater, AOSmith - Temperature changes

Ritzy Member Posts: 34
I am not knowledgeable about the workings of a water heater.  I have an AOSmith, gas-fired hot water heater for 10 years...beyond the warranty date.  The temperature of the water that this unit produced was always very warm.  Now, the temperature of the water is becoming lukewarm.   Does this mean that the water heater needs to be replaced?  Is this a potentially dangerous situation?


  • Tim McElwain
    Tim McElwain Member Posts: 4,621
    It could be a number of things

    including the age of the heater. The control could be out of calibration and may even need replaced. Based on the age of the heater it would be better to install a new heater than replace a control on an old heater.

    Have you actually measured to see what the temperature of the water is? Someone could have changed the setting on the heater.

    What area of the house did you note the drop in temp? If it was the shower it could also be the mixing valve on the shower. Another possibility is an open shut off on the washing machine and back feeding through the mixing control on the washing machine. Try shutting off the water hot and cold to the washing machine and see if it changes.

    I would also recommend getting a professional plumbing and heating tech to take a look at it.
  • Ritzy
    Ritzy Member Posts: 34
    Kitchen Water Temperature Cooler

    Thank you, Tim.  I noticed the temperature change initially on the 1st floor of a 3 story house.  Then, I noticed it on the 2nd floor in the shower.  The temperature knob was never moved...it is in its original position.  As you suggested, I will have a plumber look at the heater.  I appreciate all of your help, as always!
  • lchmb
    lchmb Member Posts: 2,997

    If you do have it replaced, read the literature that comes with the new unit. Most recommend flushing the unit to keep sediment from building in the unit which can affect it's performance down the road...
  • Tim McElwain
    Tim McElwain Member Posts: 4,621
    Yes and also

    have the anode changed every other year and you will extend the life of the unit. My last two water heaters lasted about 20 years on one and 22 on the last one.
This discussion has been closed.