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Buderus model 115/21 with a NEW LT300

ProPro Posts: 13Member
Have hooked up but NO DOMESTIC HOT WATER. Help! Have plenty of parts, but I'm missing something.
Pro (homeowner)

Comments

  • ProPro Posts: 13Member
    Have LOGMATIC controller with a RIELLO 40 burner and a WESTWOOD Ultra 10 filter. Have TIGER LOOP, but not yet installed.
  • ProPro Posts: 13Member
    Lastly, twin ROTH tanks and a reserve ( 260 gallon )tank). 3 zones, planning a a fourth ( Radiant Heat )
  • STEVEusaPASTEVEusaPA Posts: 3,844Member
    What did the installer say? Was domestic hot water enabled?
    steve
  • ProPro Posts: 13Member
    It was enabled, but no luck. I'm trying to figure it out to see if it's just a glitch or what.
    Thank you
  • HVACNUTHVACNUT Posts: 2,858Member
    edited February 6
    2107 or 2109?
    Is the indirect powered through the Logamatic or a separate relay?
    In the Logamatic, the DHW circ to line volt block Grey 24 and 25. Tank sensor wires to low volt block Grey 1 and 2.
    Is there a faucet displayed on the screen?
    You went through all the prompts?
  • GWGW Posts: 3,532Member
    Go to the relay test and make the pump go. That will tell you what’s up. Also when you scroll the big dial can you see the DHW tank temp? Some people can’t deal with the 2107. I dig them a lot
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    www.wilsonph.com
    [email protected]
  • ProPro Posts: 13Member
    Definitely a 2107.
    Went through all the prompts, but will do again and report.
    Will take input and verify.
    Will use book and set up and report.
    I thank both of you for responding.
  • ProPro Posts: 13Member
    To HVACNUT,
    Definitely a 2107.
    Powered through the Logamatic.
    Wiring wasn't changed, but appears to be correct.
    There is a faucet (#2) in the icons.
    I went through all the prompts. NO CHANGE.
    To GW,
    How do I test relay?
    GRUNDFOS recirculatory whirrs, get hot, but doesn't push water through.
    The DHW is 55 degrees. That is all.
    Here are the pictures.
    Sorry, I had a medical emergency.
    PRO



  • HVACNUTHVACNUT Posts: 2,858Member
    Hope everything is ok.
    Pics didn't come through.
    Seems like the loop is air bound and, or the pump is seized.
  • GWGW Posts: 3,532Member
    Pro get well soon. The pump makes noise but doesn’t move heat (water)?. You know how purge the circuit? There’s a specific yet simple process
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    www.wilsonph.com
    [email protected]
  • ProPro Posts: 13Member
    To HVACNUT,
    Thanks for the well wishes. Will post pics.
    Will bleed system again, but I don't think that is the problem. I've been known to be wrong though.
    To GW, Thank you for your wishes. No, I don't know how to purge system unless bleeding it
    fully is the same. Will attempt today and post with pictures. Perhaps you could give specific instructions to purge, as COLD water is the pits.
    The DHW was on, the Recirculatory pump was on, temp was set to 140 but didn't move past 55, and I have no HOT WATER.
    Thank you,
    PRO
  • HVACNUTHVACNUT Posts: 2,858Member
    edited February 9
    Yes purge and bleed have the same meaning. But to me, you purge a loop, you bleed a radiator. Why? I dunno.

    But yes, post a pic of the system so we can see if you're properly purging, or bleeding, or expelling, or displacing, or even burping.
  • ProPro Posts: 13Member
    Will DO!Pro
  • ProPro Posts: 13Member
    I have HOT WATER. The GRUNDFOS recirculatory pump was stuck. I gave it a rap (a couple) and temps started to climb. 6 degrees in 30 minutes. Pictures are enclosed. This is a 76 gallon indirect water heater so I may have to wait awhile.

  • BDR529BDR529 Posts: 65Member
    Is that the purge assembly on the vertical pipe? and behind the drip tube on the relief is a fullport ball valve? A purge on the expansion tank? Wonder what the returns look like..

    So, 6 degrees in 30 mins.. Your heat will be off until the domestic is satisfied. Hope the Mrs. is understanding.

    That tank is overkill to say the least.
  • ProPro Posts: 13Member
    I inherited this...I didn't design it. The back of the Buderus LT300 is plumbed quite natural, although the pictures didn't appear. I can always bypass the operation.
    Pro
  • HVACNUTHVACNUT Posts: 2,858Member
    If the Grundfos is a UPS15-58, make sure it's on low speed.
    The sweet spot on the LT300 is 6 GPM at 1 ft head. Even with additional piping and bends, it will flow about 9 GPM.
  • ProPro Posts: 13Member
    The GRUNFOS was intermittent so I ordered a new one. Mine is a UPS15-58 FRC unit. I was greeted by a DHW ERR message and a whiny pump ( When it worked). I'll put it in Wednesday and let you know. Thanks for the low speed tip.
    Pro
  • ProPro Posts: 13Member




    I have NO HOT DOMESTIC WATER. Replaced the GRUNDFOS because it was only operating some of the time with a GRUNDFOS UPS15-58 and it works, but NO HOT DOMESTIC WATER. Pictures attached, so what is wrong?
  • HVACNUTHVACNUT Posts: 2,858Member
    Did you purge the loop?
    If the circ is running, its gotta be air bound. Or a valve is closed.
  • ProPro Posts: 13Member
    Purged the loop twice until full water. Will purge, and listen for any tell-tale signs. Will check for valves, but all faucets flow readily. I will check 100% though. Thank you.
  • BDR529BDR529 Posts: 65Member
    Is the DHW circ wired the the recirc terminal?
  • BDR529BDR529 Posts: 65Member
    Could also have a thermistor and/or burner problem.

    You know, swap the 2107 control out for a standard aqustat and wire accordingly. It would make life easier.

    Will be no change in effcy.
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