I've had an issue with my burn pot on my LDJ 165,000 overflowing with corn a few times and I've tried the other fixes but think my problem is that it reaches the hi temp limit and shuts down the stove. That makes me think I'm in the need for a dump zone for overheating and have looked over past posts on here and other sites and have decided I'm going to use an old cast iron radiator and existing circulator that I have to act as my dump zone. My question is what type of thermostat do I use to tell it to send water to the zone and what tells it to stop sending heat toward the dump zone when the boiler temp is acceptable? Can I tie into the hi limit switch that came with the boiler to activate the circulator, again what tells it is satisfied? I don't want to or have time to constantly monitor this thing on warmer days so I need something that can be reliable. Thanks for any advise.

Guys, thanks again for all the replies and I wanted to get it back running for a few days and see if some of your suggestions helped, thus the long no reply time.

I am burnging 100% corn, 13%, very clean. I did rewire my primary pump so it runs continuously, which helped a bunch. It has been running on high fire quite a bit as my old house is poorly insulated, leaky windows and a cold wife, which seems to be resulting in large, hard clinkers. I may mix in some wood pellets, what ratio of pellets:corn can I safely burn without the smoke backing up into the hopper bin? I increased my btu setting to 132,000 and that seemed to help some and it actually goes to idle fire now some. It seems to be going through quite a bit of corn however as a full hopper is lasting me about 3- days but it's currently 6 degrees with a wind chill of -15 so my oil burner would be running a lot also.

I have attached a few pics of how I have it set up. I have it set up for 2 zones, upstairs and downstairs, but only use it as a single zone (whole house) right now as I didn't want to break into all the aspestos insulation and risk breaking old pipes. I am controlling flow into my secondary zone with the valve in front of my pump and controlling return water with my valve on the return side. Seems to be keeping my return temps acceptable, does take a while to warm the house though to satisfy the thermostat though. I would be open to suggestions as to allow me to open that up and move more hot water to the radiators.

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I also have a pic of how it is tied into my existing system. I have it set up with valves on the outflow and return side of the oil burner, allowing me to isolate each boiler. I currently have 1 thermostat coming down to a on-off-on switch so I can choose which boiler it send the signal to, which seems to be working fine. I'm using 1" pex to move water about 8' from my crossover bridge to the existing piping. I used the pex because I had it and it was easy, could be changed easily.

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Thanks again guys with all your suggestions and more are welcome as this is a learning process.

Matt

Guys, thanks again for all the replies and I wanted to get it back running for a few days and see if some of your suggestions helped, thus the long no reply time.

I am burnging 100% corn, 13%, very clean. I did rewire my primary pump so it runs continuously, which helped a bunch. It has been running on high fire quite a bit as my old house is poorly insulated, leaky windows and a cold wife, which seems to be resulting in large, hard clinkers. I may mix in some wood pellets, what ratio of pellets:corn can I safely burn without the smoke backing up into the hopper bin? I increased my btu setting to 132,000 and that seemed to help some and it actually goes to idle fire now some. It seems to be going through quite a bit of corn however as a full hopper is lasting me about 3- days but it's currently 6 degrees with a wind chill of -15 so my oil burner would be running a lot also.

I have attached a few pics of how I have it set up. I have it set up for 2 zones, upstairs and downstairs, but only use it as a single zone (whole house) right now as I didn't want to break into all the aspestos insulation and risk breaking old pipes. I am controlling flow into my secondary zone with the valve in front of my pump and controlling return water with my valve on the return side. Seems to be keeping my return temps acceptable, does take a while to warm the house though to satisfy the thermostat though. I would be open to suggestions as to allow me to open that up and move more hot water to the radiators.



I also have a pic of how it is tied into my existing system. I have it set up with valves on the outflow and return side of the oil burner, allowing me to isolate each boiler. I currently have 1 thermostat coming down to a on-off-on switch so I can choose which boiler it send the signal to, which seems to be working fine. I'm using 1" pex to move water about 8' from my crossover bridge to the existing piping. I used the pex because I had it and it was easy, could be changed easily.

[attachment:2]C:\fakepath\IMG_0719.JPG[/attachment]



[attachment:3]C:\fakepath\IMG_0716.JPG[/attachment]


Thanks again guys with all your suggestions and more are welcome as this is a learning process.

Matt

Thanks for the ideas guys. I had some time last thursday to mess with it and monitor it some more, set the primary pump up continuously and got the return temp figured out by playing with both supply and return valves to my secondary system. It worked great all day yesterday and I was gone all evening but came home and the fire was out and pot was overfilled with corn. I have some theories that with the high winds thursday and a tall existing chimney that I'm using I had my draft setting a little off for when the wind died yesterday, affecting my low fire draft. I need to clean it out and see how much clinker material I had also. I cleaned that stuff off yesterday morning so I'm not sure if that's it. I should have some time tomorrow to monitor and play with it some more. Also, would it help my situation with the output temp falling too low if I increased my btu's from 100,000? In my mind that would produce hotter water soone. Thanks again for the suggestions and I welcome anymore. I'll try to get some pics too.

Well, with some colder weather in MN and a little reconfiguration of my piping I got the boiler up and running. It runs great and does a fine job. I do have a couple questions for you all though. I have it set on 100,000 btus and I have the temps set at 180 high limit and 170 for the low. Currently when the upstairs thermostat calls for heat it will drop the outgoing temp down to the 150's. This puts my return water just under 140. I understand I don't want that. My question is if I should set my low temp higher so it will come on sooner once it starts moving water throughout my house? It is supplying cast iron radiators throughout the whole house. I will try to get some pics of how I have it plumbed and setup so you can look at what I have. Thanks.

I have it plumbed in a primary-secondary way but the Taco pump on my primary turns on at the same time as my secondary pump only when the thermostat calls for heat. Seems like I could be doing this with only 1 pump if that's how it will stay. This is the way the guy that had it before me had it set up. He was running a short distance and into 2 heat exchangers in his propane furnaces and a water heater. I have a different situation than that, basically one zone(whole house). I think I need to keep that primary pump running continuously. I have a crossover bridge with a Taco pump for my outflow to the radiators. Can I close the valve in front of that pump some and force some water to continue on my bridge and mix with my return water? I have 2 Holohan books and read through them again last night so I have a few more ideas of what it may be.

Thanks guys,

Matt

I don't have it set up to be circulating at all times. The guy I bought it from advised me it wasn't necessary due to the fact that I was only running it a short distance to where it's tied into my current boiler system. He had it with 2 heat exchangers and did it the same way. My system is currently tied into my existing system. The outflow and inflow is plumbed with 1.5" black pipe with a 1" copper crossover bridge in-between the two. I have 1" pex running straight about 7' to tie into my existing 1 1/4" iron pipe. I am supplying 2 heat to both levels of my home using cast iron radiators.

I have my aquastat set at 165 or so on the high and 150 on the low with the other setting at 10. I have it running at 100K btu's.

I have my idle timers set at the 2 and 6 like suggested for start up. I did play with it a little and went to 2 and 5 which didn't seem to do much. I need to check my existing chimney(outdoor 6" clay) tomorrow to make sure it is open and clean so I have enough draft. I have the dwyer manometer but it seems to move all over the place and I don't understand why. If the boiler is on low fire and the draft is required to support the fire where does the air come in to keep that fire going?

Am I having difficulties considering that it's mid 40's and sunny so it isn't calling for heat much? Would a continuously running primary loop require more fuel and reduce my efficiency? Is it really necessary?

I agree with your comments that a good hot fire is required on low idle to keep that large amount of corn added when it switches to high fire burning. My issue I think is that my low idle fire is not staying hot enough.

I can't really complain about mid 40's in MN in December but i'm baffled by this boiler. Thanks for any advise.

I was referred to this site by the guy I bought this from and it seems like a bunch of knowledgable people that have some experience with these boilers and hydronic systems in general. I've read 2 Dan Holohan books and learned alot from those and have gotten some tips from the guy I bought it from but I thought I'd get on here and pick some brains from a larger group.


I've added a LDJ 165,000btu boiler to replace my fuel oil boiler and I just got it started up today. I'm heating a 100yr old farmhouse with the good ol' cast iron radiators burning 100% corn, which is clean and dry(13%). I have a couple newbie questions. When it is burning on low idle the "out" temp gets up to 190 or so and the "in" temp is right around 160. When the thermostat calls for heat they both drop drastically, (120's "out" and ~100 "in"). I've done some reading on this site and the old forum and gathered that the return water should be somewhere around 140 degrees. I understand that it needs to circulate 50+ gallons of water through my radiators which results in the temp drop but is that ok for my boiler?

After it ran on low idle for a while (1+hr) the thermostat called for heat, the stove went to high fire and I went to check on it and the pot was full and almost running over. Seemed the corn was being augered in faster than it was burning. Am I correct in assuming that I needed to get more combustion air to burn that corn faster? I adjusted my draft to keep my low idle fire just burning so I don't know that I can increase that much so I opened up the combustion fan some.

Thanks!