Announcement

Collapse
No announcement yet.

Slow burner

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Slow burner

    I just spent four and a half hours waiting for 200 gallons of water to heat up on the brew kettle from 50 degrees Fahrenheit to 170 degrees Fahrenheit, and that is way too long to wait for water to heat up, or is it?
    My kettle is a gas fired CDC 15 barrel with a 400 BTU burner. With 4.5 hours of burn I would expect the burner to put out 1.8 million BTUs, theoretically it would take a little less than 300,000 BTUs to heat the water 162 degrees, from 50 to a boil. I had hoped that I could heat the water in a couple hours to boiling do to the fact that this system is old and I am positive now, highly inefficient, but I did not expect it to be this inefficient.

    Has anyone worked with this system before?
    Is this a common problem or is this unique?
    Would baffling the burn chamber work to up the efficiency, and if so how?

    Thank you for any and all the help.
    Mark Duchow
    Brew Master
    Short Fuse Brewing Co.
    Chicagoland
    "The best beer is FREE beer"

  • #2
    I have worked on a very similar system, and while it may be a bit inefficient that does seem like an excessive amount of time.

    The first area that I would investigate is the gas supply. You need to make sure that the burner is receiving adequate fuel to operate at full capacity. This means checking where gas enters the building, the meter, and the piping that leads to the burner. Depending on the length of the run, you could be starving the burner. If there are other gas appliances utilizing the same service this can also suck some energy that you need for the burner to run properly.

    I ended up having to upsize a meter and run a new 2" gas line to deal with some of these issues. If you determine that you are getting enough gas to the burner, then it is time to look at the burner itself or the firebox.
    Steve Sanderson
    RiverWalk Brewing Co.
    Newburyport, MA

    Comment


    • #3
      Originally posted by Captain Mullet
      I just spent four and a half hours waiting for 200 gallons of water to heat up on the brew kettle from 50 degrees Fahrenheit to 170 degrees Fahrenheit, and that is way too long to wait for water to heat up, or is it?
      My kettle is a gas fired CDC 15 barrel with a 400 BTU burner. With 4.5 hours of burn I would expect the burner to put out 1.8 million BTUs, theoretically it would take a little less than 300,000 BTUs to heat the water 162 degrees, from 50 to a boil. I had hoped that I could heat the water in a couple hours to boiling do to the fact that this system is old and I am positive now, highly inefficient, but I did not expect it to be this inefficient.

      Has anyone worked with this system before?
      Is this a common problem or is this unique?
      Would baffling the burn chamber work to up the efficiency, and if so how?

      Thank you for any and all the help.
      It depends of the starting temperature of the water.
      A BTU is the amount of energy required to raise 1 pound of water 1 degree Fahrenheit ... water weighs about 8.34#/gal ... so 8.34 BTU's are required to raise 1 gallon of water 1 degree F. If your starting temperature of the water was 40 degrees F ... there would be 160 degree rise to 200 degrees or ...
      1,334 BTU's are required to raise 1 gallon of water from 40 degrees to 200 degrees Fahrenheit

      Comment


      • #4
        The CDC equipment had less engineering than many other manufacturers.
        If it is a concentric ring burner, it is likely a 440k BTU burner. I have found that these burners need to have the jets cleaned out from time to time. Ideally GENTLY use the same diameter drill bit used to bore it out in the first place. McMaster has the "numbered" size drill bits, which may be on the natural gas burners.

        Baffles may help, depending on the design.

        Also very critical is the burner elevation. The top of the blue flame should just lick the kettle bottom. Imagine a kitchen pot on the stove and how important it is to place the pot at the right part of the flame. Poor flame appearance would be a symptom of too low pressure from piping pressure drop.

        Comment


        • #5
          burner

          Thank you almalkin,
          I do not believe that the problem is the gas line. The line is two inch and the pressure is good, although I think I might change out the pressure gauge to see if it is reading true.
          Mark Duchow
          Brew Master
          Short Fuse Brewing Co.
          Chicagoland
          "The best beer is FREE beer"

          Comment


          • #6
            burner

            Thank you Moonlight,

            I think you may have it right. I will clean out the jets and change the elevation and post the results, possibly in a couple days.
            Mark Duchow
            Brew Master
            Short Fuse Brewing Co.
            Chicagoland
            "The best beer is FREE beer"

            Comment


            • #7
              Just what everyone else said. I have an Economite 400/33 and it came from the East Coast to the Seattle area. The first diagnosis was that the gas regulator was designed for high-pressure gas delivery (Seattle is low-pressure), AND it was undersized anyway. Secondly, the flex hose between the regulator and the burner was undersized.

              Once you get the right fuel delivery you will need to have a boiler tech recalibrate everything including your exhaust damper. But then it'll be good to go for a long while.

              Comment


              • #8
                I was having some lag time trying to get up to a boil, I started circulating my wort slowly as it was heating and that seemed to help a lot. I guess a little circulation helps move that heat around the kettle. Anyone else do this?

                Comment


                • #9
                  Remember that you are also heating up the kettle sides and bottom. They use BTUs also.
                  Some here have said that they are using an on demand heater to start with warmer water.
                  Mike Lanzarotta
                  Commercial Real Estate Broker
                  finding space for breweries in Southern California
                  former owner and brewer, Crown City Brewery, Pasadena CA

                  Comment


                  • #10
                    Today’s burner test was the same as the other day even though I started recirculation, 2.5 hours and only 25 degrees Fahrenheit.

                    I pulled the burner apart and cleaned the jets, although they seamed pretty clean. I changed out the pressure gage and she is reading 12 psi. The sizing of the gas line shrinks down the last three feet from 2 inch to ¾ inch. Is that too much?

                    In the burn chamber there is a good baffle so I can not believe that that would be the problem. I will be repositioning the burner, possibly tomorrow, to face upwards so the flame can brush up against the bottom of the kettle.
                    Mark Duchow
                    Brew Master
                    Short Fuse Brewing Co.
                    Chicagoland
                    "The best beer is FREE beer"

                    Comment


                    • #11
                      Do you start the burners at the end of run off or do you start during run off?

                      Comment


                      • #12
                        I am running 1" pipe to the regulator and 1" flex to the burner. My boiler tech wants to go up to 1.25" on the flex because of the added turbulence.

                        Based on that info, I'd venture to guess that .75" is WAY too small for flex especially. Find a good boiler tech, or if the flex still has a label read the max BTU/H flow rating for the hose. For instance, my 1" flex is rated for 385,000 btu/h, which is a tad under what the burner is good for.
                        Last edited by TwelveBarBrews; 04-06-2012, 10:33 AM.

                        Comment


                        • #13
                          Originally posted by Captain Mullet
                          I just spent four and a half hours waiting for 200 gallons of water to heat up on the brew kettle from 50 degrees Fahrenheit to 170 degrees Fahrenheit, and that is way too long to wait for water to heat up, or is it?
                          My kettle is a gas fired CDC 15 barrel with a 400 BTU burner. With 4.5 hours of burn I would expect the burner to put out 1.8 million BTUs, theoretically it would take a little less than 300,000 BTUs to heat the water 162 degrees, from 50 to a boil. I had hoped that I could heat the water in a couple hours to boiling do to the fact that this system is old and I am positive now, highly inefficient, but I did not expect it to be this inefficient.

                          Has anyone worked with this system before?
                          Is this a common problem or is this unique?
                          Would baffling the burn chamber work to up the efficiency, and if so how?

                          Thank you for any and all the help.
                          I am interested in what you found out on the Burner.

                          Comment

                          Working...
                          X