Does Every Gasifier "Firing" Start With a Match?

[bpirger]

We are looking to buy a gasifier. It is very clear that the most efficient way to burn wood is fast and hard, using storage. Given this, and all the mentions of "firing", does every gasifier burn start with a match? Are there no coals left after say 12 hours that will just take the new load of wood of to the races?

I know this depends on all sorts of variables. So let me ask this across the range of variables:

1. Gasifier with no storage, deep winter, reasonable heat load/boiler match. Here I assume idle time will occur and this is likely to extend the burn/coal time...though clearly not the efficient way to burn.

2. Gasifier with storage (say 1000 gallons), deep winter, and again reasonable heat load/boiler output match. This is the one or two "firings" per day. Does everyone start with a match? For example, with a Garn, it does indeed appear that every firing is match lighted....maybe a load or two is burned, maybe 30-50 degrees of storage increase.

I'm used to starting a fire in October and letting it go out in April. Obviously not the efficent way to burn...but starting a fire everyday seems like perhaps it grows old. Granted, with a forced draft, it likely takes right off.

Thanks!
Bruce

 

[leaddog]

Usually there are coals so all you have to do is put in wood. If the coals are burnt down you might have to add a couple sheets of paper and some kindling but because the refactory is hot it will take off. Where you have to start is in the shoul;der seasons where the boiler has been off for a day or so. I tend to try and build a small fire every day in the colder shoulder season as it is easier to start and then in the summer I build a fire every 4 to 7 days.
leaddog

 

[Nofossil]

In my case, pretty much every fire takes a match (actually, a propane torch, but that's because I'm lazy). An average winter burn is seven hours per day, and the EKO controller runs the fan for a long time after the fire has gone out, pretty much consuming the coals. I have a 'fan disable' relay to save the coals, but I haven't hooked it up yet. Some people use a timer for that purpose.

Some of the more sophisticated gasifiers (Froling, Verbaronen) start really easily - so much so that it's not an issue at all.

 

[wood thing]

I TOO HAVE TO START A FIRE PRETTY MUCH EVERYTIME. HOWEVER ONCE IN A WHILE I CAN CATCH IT. T NOFOSSIL --- I AM INTERESTED IN YOUR FAN DISABLE RELAY. CAN YOU TELL ME MORE. THANKS

 

[stee6043]

I start a new fire every day in the dead of winter. I use a propane torch, not a match...

Wood thing, you can use simple 12 hour timer available at Lowes/HD to control the fan in lieu of more sophisticated controls. Nofossil has a killer setup, wish I had it. Unitl that day comes I use a 12 hour timer when I turn the fan on to shut it off after a burn cycle. I typically set it for 4-6 hours depending on the wood and the weather. This prevents the fan from running until the EKO decides it's out of wood, which can take a long time (especially with storage that maintains high return water temps).

 

[WoodNotOil]

The Tarm I have has a sensor that goes in the box where the flue gas exits after going through the hx tubes. That can sense when the fire is nearly out and shuts off the fan. All winter I have enough coals to not have to start a new fire. My heat load is very large and my boiler is not, so it burns most days all but the sunny afternoon hours while I am away.

Starting fires is really simple once you get the hang of it and since the wood has to be dry for a gasser, it starts off pretty quick. Including loading the wood, I am at a new fire for about 10 minutes and then I come back after another 20 minutes to close the door all the way and turn the draft fan on. As the fires space out in the should season there is more lighting and then I go 4+ days between fires in the summer. To help with draft in the summer I take the cap off of the tee in my chimney pipe just behind the boiler and point my propane torch up it for a minute. After that the draft is flowing strong enough that I don't have smoke out of the door when lighting.

 

[Nofossil]

I TOO HAVE TO START A FIRE PRETTY MUCH EVERYTIME. HOWEVER ONCE IN A WHILE I CAN CATCH IT. T NOFOSSIL --- I AM INTERESTED IN YOUR FAN DISABLE RELAY. CAN YOU TELL ME MORE. THANKS

The fan disable relay is intended to accomplish the same thing as the timer described above. The only difference is that I have a controller that monitors flue temp, combustion temp, and outlet water temp so I know when the fire has died down to a bed of coals. In theory that should let me kill the fan at the ideal time.

 

[bpirger]

Thanks for all the responses....sounds like a fresh start is often required....though not always. Perhaps some fine control of the blower might perserve a bed of coals.

Thanks to all! Have to make some decisions....

 

[dirttracker]

On my Tarm (Solo-40 with 500 gal storage) I usually don't have to re-light in the dead of winter. I usually burn twice per day during this time and usually have enough coals to get a fire going again. During spring and fall, when I'm only burning once per day, it's about 50% having to re-light. Sometimes there are enough live coals left and sometimes not. I have the fan set to turn off and leave a few coals in the firebox as these work well for re-starting. I just pile them up on a couple of splits directly above the nozzle opening and light the coals with a torch - no paper needed. I always have to relight in the summer, I burn every 2 or 3 days for DHW.

I have tried to fine tune the shut off stack temperature to leave a few more coals, but then you risk having the unit shut off if it goes into idle mode. I suspect the best way to do this would be based on temperature rise on the water through the boiler. If the temp rise gets too low the boiler is out of fuel and can be shut down. I may try this someday.

 

[RobC]

During winter I will fire once a day. I use the torch trick and put 3 or 4 pieces of Fatwood at bottom, pile wood on top and light from underneath. One bulk box of Fat wood (25lbs ?) can be had pretty cheap (1.25/ lb) and lasts about a year.
Rob

 

[emesine]

Bpirger,

What is your setup? Are you doing forced air? In-floor radiant?

With storage, it makes a large difference. Basically, low temperature heat transfer means such as in-floor systems can utilize storage much more effectively than water-air heat exchangers. For example:

If your in-floor radiant needs 110F water, then you can use your storage down to 110F. If you heat your storage to 180F, then 180-110 is a total of 70F differential. You can get a lot of storage from a relatively small amount of water.

On the other hand, if you are using a forced air system you will need more like 150-160F water. 180-160 is only 20F differential. It probably isn't worth doing storage at all- you may just as well buy a gasifier designed to run 24 hours a day.

Just a few thoughts....

Andrew

 

[Gooserider]

Bpirger,

What is your setup? Are you doing forced air? In-floor radiant?

With storage, it makes a large difference. Basically, low temperature heat transfer means such as in-floor systems can utilize storage much more effectively than water-air heat exchangers. For example:

If your in-floor radiant needs 110F water, then you can use your storage down to 110F. If you heat your storage to 180F, then 180-110 is a total of 70F differential. You can get a lot of storage from a relatively small amount of water.

On the other hand, if you are using a forced air system you will need more like 150-160F water. 180-160 is only 20F differential. It probably isn't worth doing storage at all- you may just as well buy a gasifier designed to run 24 hours a day.

Just a few thoughts....

Andrew

Not completely true, as there is somewhat of a compensating factor in that "shoulder season" temps outside are generally warmer, which means that you will not need as hot a supply water in the HX to keep the house warm (though running a cooler HX will increase your blower on time) Thus while you might need that 150-160°F water in the dead of winter, you might only need 120-130°F in the spring and fall, which is when storage does the most good in any system... Of course the lower temp systems will also see the same benefit....

Also, while there are limits, one can also decrease the temp requirements on an FHA system by going with an oversized HX

Gooserider

 

[emesine]

One last point-

"Starting a fire" with a gasifier is easier than building a fire in your hearth. I have a Wood Gun (forced air system.) I lit a fire in it today to test the system. I turned on the fan and piled a few cold charred bits of wood over the nozzle along with a few pieces of cord wood. Timeline:

0- held soldering torch to wood/dead coals for 15 seconds.
1 minute: few coals glowing
3 minutes: flame and roaring noise
4 minutes: glow from coals begins to be so bright I don't like looking at it
5 minutes: close the door because the heat radiating from the fire is burning my face

Starting a fire with a gasifier, at least with a forced air system, is amazingly easy.

Andrew

 

[heaterman]

Most Garn users find the sweet spot rather quickly that will leave a few coals in the firebox. They simply rake them up a little and throw in another load of wood, set the timer to about 2-1/2 to 3 hours and close the door. Gotta get a video of my 11 year old grand daughter firing their Garn........

 

[DaveBP]

I want to put a plug in for the true pyromaniacs among us.

I enjoy making a fire from scratch. Give me a hatchet and some dry, clear-grain softwood and get outta my way!

I have never gotten over my Boy Scout obsession with making a roaring fire with one match.

It's not even hard to do. All you need is dry wood. I sometimes think that is the catch. Maybe the kindlephobiacs that post here don't know what truly dry wood can do for your life. All the dry kindling that you can hold in one hand and a few pieces of newspaper will turn a wheelbarrow-load of really dry hardwood into an inferno in a few minutes. Does it get any better than that?

OK. I just got home near midnight after 8 hours of trying to get usable computer code out of what turned out to be a faulty 3D model. Please forgive me for indulging the pleasure of taking a hatchet to something that makes a lot of noise. But my point is serious. Some folks don't mind making a fire from the beginning every time. I, for one, also enjoy the ritual of grinding coffee beans and manually pouring boiling water over them every morning.

I guess there's just no hope for us.

 

[emesine]

There's nothing like a good one-match fire. How about this-

Pile some coals from the previous fire (cold and dead) over a nozzle. Turn on the draft inducer and knock a spark from a flint and tinder directly onto the coals. I bet it would light directly from the charred wood. If not, it would certainly light with a small square of char cloth on top of the pile of coals.

Not as practical as a simple propane torch, but sounds like fun.

Andrew

 

[emesine]

OK DaveBP, it works. I was out at the house trying out the system today. I know it's summer, but I am doing extensive, important testing (read playing with my new toy.) I got out to the house and did NOT have a match to light the boiler. I did find my flint and tinder with two remaining one inch squares of char cloth. I piled up some dead coals and they lit up beautifully with a flint and tinder.

Andrew

 

[shoeboxlen]

i personaly use a propane torch with a push button ignitor. throw some kindling in there a little news paper fire is up and going in a few minutes tops.