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Rinnai E110C DHW temperature too hot

I have a Rinnai E110C installed by plumber almost a year ago.  The DHW has always been too hot.  I checked the online manual from <a href=""></a> which does mention about a PARAM code (31) to set the DHW temperature.  However, on my unit, I can't find that PARAM code of 31 (DHW temperature).

I only have code 43 which sets the "Maximum power DHW in kW".  The value is 36.6 by default.  Is this something I can set to lower in order to bring down the DHW temperature?

I set it to 15 and it is still quite hot.  It seems to be better than 36.6 but I just want to confirm with the pros before setting it too cold so my wife will yell at me :-)



  • Ironman
    Ironman Member Posts: 6,547
    edited October 2012
    Not Temp....

    But the maximum firing rate expressed in KW. 1KW = 3,413 btu's. You've limited how much the burner can fire, not its max. temp. You need to set it back where it was because you won't have enough hot water when more than one faucet is open.

    I recommend you call Tech. support for help.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • Aston
    Aston Member Posts: 4
    Set it back

    Thanks for prompt reply.  I set it back to the original setting of 36.6 now.

    I use the info to see the DHW temperature.  It IS set to 130.  May be that's the correct setting?

    Sounded like there isn't a way to adjust the DHW temperature of my unit...
  • Jack
    Jack Member Posts: 1,045
    Do you have a

    tempering valve on the unit. The E75 and 110 C models require the field installation of a tempering valve .
  • Aston
    Aston Member Posts: 4
    edited October 2012
    I don't know...

    Do you mean the mixing valve?  If so, then no.  They didn't install one.

    I'll check with the plumber...

  • Aston
    Aston Member Posts: 4
    Mixing valve

    Is there a particular brand/model I should install for E110c?  May be I can just go to HomeDepot and get one and solder it myself...
  • kcopp
    kcopp Member Posts: 3,815
    a honewell...

    am 100 series valve would be my choice. A taco 5000 series second. If the  Mfg calls for one I am surprised the inspector did not pick up on  that missing.
This discussion has been closed.