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Cold start

kevsul1
kevsul1 Member Posts: 28
in THE MAIN WALL
In a cold start boiler do you to have the supply tapped into the return right off the boiler

Comments

  • STEVEusaPA
    STEVEusaPA Member Posts: 6,505
    Do you mean a bypass?

    There was an error rendering this rich post.

  • kevsul1
    kevsul1 Member Posts: 28
    Yes
  • Gordy
    Gordy Member Posts: 9,546
    A boiler bypass in its simplest form takes a portion of the return water , and bypasses the boiler mixing with the supply water.

    Add some valves, and you can control how much gets diverted around the boiler.

    Or you can use a 3 or 4 way valve that insures 100% boiler protection.
  • exqheat
    exqheat Member Posts: 194
    I did a cold start on a Weil boiler LGB6 in a 58 family building. Mild day Yonkers 2-16-23.
    The boiler did not have a bypass. I wanted to recommend one. I thought we could save a lot of energy with cold start in these warming seasons ( no snow). First I wanted to see how the boiler would perform without the bypass. It has been doing well since 2003 without it. So what happened?

    02/16/23 02:14.31 PM Thermostat On Temp = 94 HWT = 255 deg.
    temp every 10 seconds
    Temp = 94 HWT = 255 deg.

    > Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 95 HWT = 255 deg.
    Temp = 96 HWT = 255 deg.
    Temp = 97 HWT = 255 deg.
    Temp = 98 HWT = 255 deg.
    2 20pm

    > Temp = 99 HWT = 255 deg.
    Temp = 100 HWT = 255 deg.
    Temp = 101 HWT = 255 deg.
    Temp = 102 HWT = 255 deg.
    Temp = 103 HWT = 255 deg.
    Temp = 104 HWT = 255 deg.
    Temp = 105 HWT = 255 deg.
    Temp = 106 HWT = 255 deg.
    Temp = 107 HWT = 255 deg.
    return 90

    > Temp = 107 HWT = 255 deg.
    Temp = 109 HWT = 255 deg.
    Temp = 109 HWT = 255 deg.
    Temp = 110 HWT = 255 deg.
    Temp = 111 HWT = 255 deg.
    Temp = 112 HWT = 255 deg.
    Temp = 113 HWT = 255 deg.
    Temp = 114 HWT = 255 deg.
    Temp = 115 HWT = 255 deg.
    Temp = 116 HWT = 255 deg.
    Temp = 116 HWT = 255 deg.
    Temp = 117 HWT = 255 deg.
    Temp = 118 HWT = 255 deg.
    Temp = 119 HWT = 255 deg.
    Temp = 120 HWT = 255 deg.
    Temp = 121 HWT = 255 deg.
    Temp = 122 HWT = 255 deg.
    Temp = 123 HWT = 255 deg.
    Temp = 123 HWT = 255 deg.
    Temp = 124 HWT = 255 deg.
    Temp = 125 HWT = 255 deg.
    2 25pm

    > Temp = 126 HWT = 255 deg.
    Temp = 126 HWT = 255 deg.
    boiler 235

    > Temp = 127 HWT = 255 deg.
    boiler 135

    > Temp = 128 HWT = 255 deg.
    2 2pm

    > Temp = 129 HWT = 255 deg.
    2 26pm

    > Temp = 130 HWT = 255 deg.
    Temp = 130 HWT = 255 deg.
    02/16/23 02:23.49 PM Thermostat Off Temp = 131 HWT = 255 deg.
    Temp = 131 HWT = 255 deg.
    Temp = 132 HWT = 255 deg.
    Temp = 132 HWT = 255 deg.
    Temp = 133 HWT = 255 deg.
    Temp = 133 HWT = 255 deg.
    Temp = 134 HWT = 255 deg.
    Temp = 134 HWT = 255 deg.
    Temp = 135 HWT = 255 deg.
    Temp = 136 HWT = 255 deg.
    Temp = 136 HWT = 255 deg.
    Temp = 137 HWT = 255 deg.
    Temp = 137 HWT = 255 deg.
    Temp = 138 HWT = 255 deg.
    Temp = 138 HWT = 255 deg.
    Temp = 138 HWT = 255 deg.
    Temp = 139 HWT = 255 deg.
    Temp = 139 HWT = 255 deg.
    Temp = 139 HWT = 255 deg.
    Temp = 140 HWT = 255 deg.
    Temp = 140 HWT = 255 deg.
    Temp = 140 HWT = 255 deg.
    Temp = 140 HWT = 255 deg.
    Temp = 140 HWT = 255 deg.


    From 98 F at 2:14 to 140F at 2:27 PM elapsed time 14 minutes


    >02/16/23 02:27.26 PM Thermostat On Temp = 141 HWT = 255 deg.
    Temp = 141 HWT = 255 deg.
    02/16/23 02:27.27 PM Thermostat Off Temp = 141 HWT = 255 deg.
    Temp = 141 HWT = 255 deg.
    Temp = 141 HWT = 255 deg.
    Temp = 141 HWT = 255 deg.
    Temp = 141 HWT = 255 deg.

    Temp = 145 deg.
    02/16/23 02:28.30 PM Thermostat Off Temp = 145 deg.
    02/16/23 02:28.30 PM Source Off Temp = 145 deg.
    02/16/23 02:30.14 PM Thermostat On Temp = 145 deg.
    02/16/23 02:30.41 PM Thermostat Off Temp = 145 deg.
    02/16/23 02:31.12 PM Thermostat On Temp = 145 deg.
    02/16/23 02:37.35 PM Thermostat Off Temp = 145 deg.
    02/16/23 02:38.01 PM Thermostat On Temp = 145 deg.
    menu
    1 ) Analysis Interval = 60 min.
    2 ) System Startup Delay = 1 min.
    3 ) Demand Ratio Ideal = 70 %
    4 ) Actual Demand Ratio Min = 10 %
    5 ) Startup Temperature = 160 deg.
    6 ) Deg Change Increment = 3 deg.
    7 ) Range Differential = 15 deg.
    8 ) High Temp Absolute = 190 deg.
    9 ) High Temp Safety = 212 deg.
    10 ) Low Temp Absolute = 135 deg.
    11 ) Low Temp Safety = 0 deg.
    12 ) Temperature Averaging = 5 sec.
    13 ) Thermostat Polarity = 1
    14 ) HotWaterLowTemp = 130 deg.
    15 ) ColdStart = 1

    There was no banging. How much condensate damage can happen in 15 minutes?

    .
    John Cockerill Exquisite Heat www.exqheat.com Precisions boiler control from indoor reset.
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 9,386
    exqheat said:

    I did a cold start on a Weil boiler LGB6 in a 58 family building. Mild day Yonkers 2-16-23.
    The boiler did not have a bypass. I wanted to recommend one. I thought we could save a lot of energy with cold start in these warming seasons ( no snow). First I wanted to see how the boiler would perform without the bypass. It has been doing well since 2003 without it. So what happened?

    02/16/23 02:14.31 PM Thermostat On Temp = 94 HWT = 255 deg.
    temp every 10 seconds
    Temp = 94 HWT = 255 deg.


    > Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 94 HWT = 255 deg.
    Temp = 95 HWT = 255 deg.
    Temp = 96 HWT = 255 deg.
    Temp = 97 HWT = 255 deg.
    Temp = 98 HWT = 255 deg.
    2 20pm

    > Temp = 99 HWT = 255 deg.
    Temp = 100 HWT = 255 deg.
    Temp = 101 HWT = 255 deg.
    Temp = 102 HWT = 255 deg.
    Temp = 103 HWT = 255 deg.
    Temp = 104 HWT = 255 deg.
    Temp = 105 HWT = 255 deg.
    Temp = 106 HWT = 255 deg.
    Temp = 107 HWT = 255 deg.
    return 90

    > Temp = 107 HWT = 255 deg.
    Temp = 109 HWT = 255 deg.
    Temp = 109 HWT = 255 deg.
    Temp = 110 HWT = 255 deg.
    Temp = 111 HWT = 255 deg.
    Temp = 112 HWT = 255 deg.
    Temp = 113 HWT = 255 deg.
    Temp = 114 HWT = 255 deg.
    Temp = 115 HWT = 255 deg.
    Temp = 116 HWT = 255 deg.
    Temp = 116 HWT = 255 deg.
    Temp = 117 HWT = 255 deg.
    Temp = 118 HWT = 255 deg.
    Temp = 119 HWT = 255 deg.
    Temp = 120 HWT = 255 deg.
    Temp = 121 HWT = 255 deg.
    Temp = 122 HWT = 255 deg.
    Temp = 123 HWT = 255 deg.
    Temp = 123 HWT = 255 deg.
    Temp = 124 HWT = 255 deg.
    Temp = 125 HWT = 255 deg.
    2 25pm

    > Temp = 126 HWT = 255 deg.
    Temp = 126 HWT = 255 deg.
    boiler 235

    > Temp = 127 HWT = 255 deg.
    boiler 135

    > Temp = 128 HWT = 255 deg.
    2 2pm

    > Temp = 129 HWT = 255 deg.
    2 26pm

    > Temp = 130 HWT = 255 deg.
    Temp = 130 HWT = 255 deg.
    02/16/23 02:23.49 PM Thermostat Off Temp = 131 HWT = 255 deg.
    Temp = 131 HWT = 255 deg.
    Temp = 132 HWT = 255 deg.
    Temp = 132 HWT = 255 deg.
    Temp = 133 HWT = 255 deg.
    Temp = 133 HWT = 255 deg.
    Temp = 134 HWT = 255 deg.
    Temp = 134 HWT = 255 deg.
    Temp = 135 HWT = 255 deg.
    Temp = 136 HWT = 255 deg.
    Temp = 136 HWT = 255 deg.
    Temp = 137 HWT = 255 deg.
    Temp = 137 HWT = 255 deg.
    Temp = 138 HWT = 255 deg.
    Temp = 138 HWT = 255 deg.
    Temp = 138 HWT = 255 deg.
    Temp = 139 HWT = 255 deg.
    Temp = 139 HWT = 255 deg.
    Temp = 139 HWT = 255 deg.
    Temp = 140 HWT = 255 deg.
    Temp = 140 HWT = 255 deg.
    Temp = 140 HWT = 255 deg.
    Temp = 140 HWT = 255 deg.
    Temp = 140 HWT = 255 deg.


    From 98 F at 2:14 to 140F at 2:27 PM elapsed time 14 minutes


    >02/16/23 02:27.26 PM Thermostat On Temp = 141 HWT = 255 deg.
    Temp = 141 HWT = 255 deg.
    02/16/23 02:27.27 PM Thermostat Off Temp = 141 HWT = 255 deg.
    Temp = 141 HWT = 255 deg.
    Temp = 141 HWT = 255 deg.
    Temp = 141 HWT = 255 deg.
    Temp = 141 HWT = 255 deg.

    Temp = 145 deg.
    02/16/23 02:28.30 PM Thermostat Off Temp = 145 deg.
    02/16/23 02:28.30 PM Source Off Temp = 145 deg.
    02/16/23 02:30.14 PM Thermostat On Temp = 145 deg.
    02/16/23 02:30.41 PM Thermostat Off Temp = 145 deg.
    02/16/23 02:31.12 PM Thermostat On Temp = 145 deg.
    02/16/23 02:37.35 PM Thermostat Off Temp = 145 deg.
    02/16/23 02:38.01 PM Thermostat On Temp = 145 deg.
    menu
    1 ) Analysis Interval = 60 min.
    2 ) System Startup Delay = 1 min.
    3 ) Demand Ratio Ideal = 70 %
    4 ) Actual Demand Ratio Min = 10 %
    5 ) Startup Temperature = 160 deg.
    6 ) Deg Change Increment = 3 deg.
    7 ) Range Differential = 15 deg.
    8 ) High Temp Absolute = 190 deg.
    9 ) High Temp Safety = 212 deg.
    10 ) Low Temp Absolute = 135 deg.
    11 ) Low Temp Safety = 0 deg.
    12 ) Temperature Averaging = 5 sec.
    13 ) Thermostat Polarity = 1
    14 ) HotWaterLowTemp = 130 deg.
    15 ) ColdStart = 1


    There was no banging. How much condensate damage can happen in 15 minutes?

    .
    In 15 minutes not much...
    But I have a felling there were many, many 15 minute events just like this over the last 20 years. Enough to cause a problem.

    Also, I'm not sure of the measurements you were posting. Where was the first number Temp = 140 measured from at 2:27 PM? I am thinking the return water to the boiler maybe, but it could be the supply. And the second number at 02:14.31 PM Thermostat On... HWT = 255 deg. and it stayed at 255 the entire time. Where was that measured from? The vent opening to the chimney?

    These numbers assume that we all know what you are talking about, where the measurements were taken and perhaps what control system you have.

    Also there is a question you posed.
    So what happened?

    So, I have several answers to that query, My daughter got married, I now have a grandson, I sold my business and retired. My son just got married last year. But somehow I don't think that is what you were inquiring about. So I will add to your query ... What happened to WHAT?

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

  • Mad Dog_2
    Mad Dog_2 Member Posts: 7,519
    On our Burnham V 9s, We like a blend pump on the first tee off the supply directly  to the return and wired in series to a Honeywell 4006A (Breaks on rise).   Thermometers in the right spots helps u dial in the safe boiler temp to prevent thermal shock and SFGC.  MAD DOG
    Consulting by Mad Dog & Matt Jr.
    EdTheHeaterMan

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