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not enough hot water

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newagedawn
newagedawn Member Posts: 586
installed a boiler with domestic coil recently and the people are having a hard time with the hot water.
they have very cold water coming into the house like 50 degrees. i already took the tempering valve out and turned up the aquastat, still not enough hot water. i'm stumped any suggestions on what to do !!!
"The bitter taste of a poor install lasts far longer than the JOY of the lowest price"

Comments

  • Ironman
    Ironman Member Posts: 7,379
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    Put in an indirect.

    You didn't mention the size of the boiler or the actual domestic load, but the coil is heating water instantaneously, so you're limited by the output of the boiler. You need storage.

    Installing and indirect and changing the control strategy to
    "On demand" will probably reduce energy consumption by at least 30%.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
    Brewbeer
  • ChrisJ
    ChrisJ Member Posts: 15,768
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    To me, 50° is fairly warm water, ours drops into the 30s during the winter.

    That said, of course you have hot water problems with a domestic coil. They're awful.

    I agree with @Ironman, an indirect is the only solution, aside from a totally separate water heater.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Big Ed_4
    Big Ed_4 Member Posts: 2,805
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    Well a coil is still a coil .. Assumed they had one before . Check the shower heads make sure they are not pulling over 2GPH .People like high water volume but ... Coil may be stamped its an 5GPH but don't believe in it ..

    I remember an batch of Peerless coils that were wound too tight , we had to stretch them before install, to increase water contact and internal flow ..

    Any bypass will kill the hot water .. Single leaver faucets could bypass though defective valve cartridge

    There was an error rendering this rich post.

    Qing
  • BobC
    BobC Member Posts: 5,479
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    I had a coil in a steam boiler for 12 years and never had a problem with hot water but the household only had one person. i did not like running the steam boiler in the summer so when I bought a house with the same setup one of the first things I did was to have a 30 gal standalone gas hot water heater installed.

    It happens both the boilers were the old oil fired Delco DBS5 steam boiler, which were 2 to 3 times larger than they had to be. If you downsized the boiler when you put in the new boiler that might explain why the hot water problem cropped up.

    A standalone tank hot water heater or an indirect may be the solution.

    Bob
    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • bob eck
    bob eck Member Posts: 930
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    Check the GPM flow rate of the shower heads. Reduce them to 1.5 GPM flow.
    You could come out of the domestic coil and dump the hot water into a 50 gallon electric water heater. Wire up the electric water heater the elements can maintain the hot water in the water heater.
    Turn the thermostat on the electric water heater all the way up.
    Then install a Honey
  • bob eck
    bob eck Member Posts: 930
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    Honeywell or Cash Acme water heater mixing valve kit to mix the water temp to 120 degrees.
    Or just install a indirect water heater as another zone on the boiler and us a control to let the indirect water heater to have priority.
  • ChrisJ
    ChrisJ Member Posts: 15,768
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    If anyone ever installed a 1.5GPM shower head in my house it'd be the last visit I ever had from them.


    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
    BoonBTU
  • Gordy
    Gordy Member Posts: 9,546
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    Agreed. 2.5 gpm with an aeration spray is about it, with decent water pressure. There comes a point where you end up in the shower longer with anything lower in gpm shower heads.
    ChrisJbob eck
  • newagedawn
    newagedawn Member Posts: 586
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    thanks for all the tips, but it was the aquastat, the hydrostat ( i hate these) had a faulty temp probe, replaced it and everything is fine, FYI
    "The bitter taste of a poor install lasts far longer than the JOY of the lowest price"