Yep, you guessed it. You have more fuel than air available to combust it. You can also get this with over sized loads of wood and/or very dry wood. If you want to experiment crack the door open to the first stop on the handle and see if it quits. Be prepared though for a bit of a POOF when you open it under those conditions. DO NOT swing the door wide open or you'll experience what I call Central Boiler Syndrome (CBS) The owners of those things invariably seem to walk about missing their eye brows for some strange reason.
I have an installation on a large dairy farm which has a pair of 2000's hooked up to about 7,000 sq ft or radiant floor plus domestic hot water (about 900 gallons per day of 160*+) Those babies get a workout especially with the inconsistent operation that comes from many different people doing the firing. I walked into the boiler room one day last winter and I could feel the pressure change in my ear drums. The 9x12' overhead door was actually moving in and out as the Garns tried to get enough breath. Nothing to do but let the fire go through its cycle and then warn the owner about over firing. No harm was done but it was rather interesting to physically experience low frequency sound waves like that.
You'll learn that it really doesn't take a lot of kindling to get a fire established in a Garn if your wood is anywhere near what it should be.
tat, besides not needing much kindling to start a induced fire, i have found that if you elevate the load of wood slightly off the firebrick, and be mindfull to try to mix the wood load with some slower burning or larger splits. the problem magnifies with any wood if it is not stacked tightly. as steve suggests if you get into door slamming puffing mode, crack the door carefully and ride it out,attended, untill the combustibles have been reduced.
Hi;
I found when the chamber is cool (first load), I only place a small load and it warms the chamber up or I will get blowback....then when I load the second load I load a good load.. about 3/4 full or better and it works good with no puffing. Two loads takes me fron 120F to 200F with a heating load on for the first 20 minutes so.Usually about 3 1/2 hrs. of burning..then a bed of coals for the next 1/2 hour with no fan. This does me 2 days with the outdoor around 15 F.
Hpoe this helps
I did try it at one point but couldn't get much heat from the boiler so I removed it. Probably has it's purpose..maybe somebody burning pallets?
Paul Duguay:Hi; I found when the chamber is cool (first load), I only place a small load and it warms the chamber up or I will get blowback....then when I load the second load I load a good load.. about 3/4 full or better and it works good with no puffing. Two loads takes me fron 120F to 200F with a heating load on for the first 20 minutes so.Usually about 3 1/2 hrs. of burning..then a bed of coals for the next 1/2 hour with no fan. This does me 2 days with the outdoor around 15 F.
Paul - I am amazed at your efficiency. I am realizing that I have some huge losses going on. Today I fired my 2000 up to about 195, and less than 8 hours later it was down to 182. I'll be firing it again before I go to bed.
I still have to finish my controls, as I have the P&S pumps circulating water 27/7. And my pipes are not fully insulated yet, with about 65' of piping in an uninsulated garage. The garage is TOASTY right now, so I am probably losing as much heat to it as I am to the house load.
More to do, more to learn.
Tattooz:Loaded up the unit tonight, I am still not heating I have one more bridge to cross..... Might have put to much paper in ... all the sudden the door started shaking in and out......?
Yep - it's happened to me twice now. Luckily not too bad, and it dissipated in less than 10 minutes. I used a bit too much of some very dry scrap dimensional lumber and that caused the latest episode. The first time I tossed in a fairly large piece of uncoated corrugated paperboard.
besides mixing m/c content and split sizes and packing wood tightly,and elevating wood slightly off firebrick floor, try loading wood with kindling in the center of the load,not at the bottom and ignite the center. these are all things i have found to work, based on the content of wood load.
Hi Jim;
It ain't rocket science.....4 sticks of kindling, 1/2 newspaper (towards the door), load your wood (half full) towards the back, lite fire, set your timer for 3 1/2 hours, have a beer and return in 1 hour, load it 3/4 full and go to bed.
It is intended to be simple and it is.
LOL
Paul
Paul Duguay:Hi Jim;It ain't rocket science.....4 sticks of kindling, 1/2 newspaper (towards the door), load your wood (half full) towards the back, lite fire, set your timer for 3 1/2 hours, have a beer and return in 1 hour, load it 3/4 full and go to bed. It is intended to be simple and it is. LOL Paul
OK wise guy! Starting and burning are the easy part. What I was impressed with was getting two days of heat from a single burn. You must have much lower heat loss than I. I went 24 hours between burns for the first time yesterday, but the temps were in the 40s during the day and low 30s at night. I usually need two burns a day.
Here's a for ya!
Jim;
Looking at your numbers....you mentioned two burns per day......if each burn is similar to mine ( 120F to 200F), I believe that would be about 3 million BTUs per day (with your 2000). With an average of 20 million BTUs per cord (dry seasoned hardwood) you would be burning one full cord per week. Is your consumption really that high?
Paul Duguay:Jim; Looking at your numbers....you mentioned two burns per day......if each burn is similar to mine ( 120F to 200F), I believe that would be about 3 million BTUs per day (with your 2000). With an average of 20 million BTUs per cord (dry seasoned hardwood) you would be burning one full cord per week. Is your consumption really that high?
Paul - No, I am not consuming that much wood, and my tank temp range is usually 150+ -> 180+ for each burn, sometimes even less. I am burning about a half cord per week. I am also still trying to finish insulating the S&R lines in my garage. I have a run of about 55 feet underground, and another 65 feet above ground in my garage. The heat loss from the black iron primary loop and the two 65 foot runs of 1.25" PEX have kept the garage well above 60 degrees despite the cold. I should have that reigned in before Christmas. I intend to heat the garage eventually, but not in this manner!
Hi Jim. I installed a Garn 2000 back in 2003 for our new house and garage with a total of about 6300 sq. ft. We heat everything to 70 degrees and now burn approx. 11 to 12 cord a winter. Usually only take Garn up to 140 degres in all outside temps, mixing valve is set at 105 degrees, usually morning water temp is 80 - 90 degrees after no firing of 20 hours.Usually take boiler up to 185 degrees a couple of times a year to kill of any bacteria in the water.
A little of my history. In 2005 we installed 2 Garn 2500 in line to heat a greenhouse complex of 20,000 sq ft., burned approx 125 cord of firewood between the 2 of them, still needed to burn some propane. Before we burned regular firewood we burned hardwood slabs, approx 240 bundles per winter.
I have used the brick before to help decrease the puffing but I found that if you don't have real dry wood or lots of newspaper right inside the door you should not have a problem. Push your wood to the back farther also helps alot.