Wood boiler setup questions

[quest79]

Hello everyone. I have recently purchased a home that has both an oil boiler and a wood boiler system tied together. I have used many wood stoves in my time but never a wood boiler. the wood boiler is a kerr titan. I have a single aquastat that shuts off the oil boiler and starts a circulator between the two boilers at 140 degrees. beside that there is a double aquastat that closes the draft on the door at around 180 degrees and at 200 degrees it turns on a circulator to the dump zone. I'm just wondering if these settings are ok and also I have it set so when the draft closes it closes completely. is this right ? any info would be appreciated thanks

 

[mike van]

Your settings are about the same as I used for 16 years on my Harman setup. I had 190 instead of 200 for the dump. That one did click on a few times, as some piece of crud would find it's way into the hinge on the damper door & make it stick open. My setup was a creosote factory, despite good dry wood, the auto damper would snuff a fire down for long periods when there was no demand. The [masonry] chimney was thick with that hard glassy creosote that I believe to be bulletproof. Except when it burns, then it kind of looks like Mt St Helens.

 

[quest79]

Your settings are about the same as I used for 16 years on my Harman setup. I had 190 instead of 200 for the dump. That one did click on a few times, as some piece of crud would find it's way into the hinge on the damper door & make it stick open. My setup was a creosote factory, despite good dry wood, the auto damper would snuff a fire down for long periods when there was no demand. The [masonry] chimney was thick with that hard glassy creosote that I believe to be bulletproof. Except when it burns, then it kind of looks like Mt St Helens.

How often did you clean your pipes and chimney during burn season

 

[mike van]

I would pull a brush down through every few weeks, you could do it every few hours with that glassy creosote and not budge it. I never had any luck with the chemical stuff, the creosote logs, etc.Maybe a stainless liner would have helped? Water over the dam now, 4th year with a Garn, no chimney cleaning needed.

 

[peakbagger]

Your setup is unfortunately a recipe for creosote buildup especially in shoulder season, every time the damper closes while there is wood in the boiler, the boiler swaps into incomplete combustion and quickly will start to generate creosote. You have a choice, clean the chimney and boiler frequently or only run it during really cold conditions where the boiler outlet matches the heating demand. If you insist on running it during shoulder season you need to do very light loads and get used to starting fires frequently. I had that setup for several years after I got my "free" boiler. It was great for really cold conditions but it didn't make as much of dent in my wood consumption as I thought it would. You are not doomed, just add storage and then the damper closed operation is not an issue.

A lot of older wood boiler setups run the circulator pump 24/7, it does eat a lot of power and also keeps the oil boiler warm so that some heat is being lost up the stack via the oil boiler heat exchanger. There are solutions to this but it requires replumbing and the installation of something called a hydraulic separator.

 

[warno]

If water temps are up and refractory is warm how long does a gasifier boiler take to start clearing up on a new fire? not a reload but say the boiler sat over night and it's a new fire in the morning.

 

[Beagle Dad]

i have a Froling 20, when I start a new fire after the previous one has burned out 6 hours earlier it takes about 5 minutes for the flue to burn clean. the water in the boiler will still be 150F, my wood has a moisture content of 10 to 12 percent

 

[maple1]

5 minutes tops. But even before that, the fire is just barely getting going so very little smoke.

 

[warno]

Just realized I high jacked this thread on accident. for those who answered my question on gasifiers pleases report to my "chimney questions" thread.

Sorry for this, quest79.