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Gasifier

Minister of Fire
Apr 25, 2011
3,211
St. Lawrence River Valley, N.Y.
Do any of you with gasification boilers run them in the summer time for domestic hot water? (Without storage) I am wondering if each night, after dinner, I could burn some of that free wood I can get by building a fire just big enough to warm up the boiler and have that heat my 50 gallon DHW superstore tank. That would seem to be plenty of hot water for the showers in the morning and the dishwasher for that matter. I think it would stay plenty hot for 8-10 hours. I know it will take some time to learn how much wood that will take but I am just curious. It would beat paying for the oil for 5 months and give me a chance to do those initial burns for the boiler start up. This could get me use to running the thing before the cold season hits and I would be through some of that learning curve by then. Thanks for any input. I appreciate it.
 
Technically the answer to your question is yes - you COULD heat DHW year round. But, strike one is the basement install. Standby losses from a boiler in the basement help to heat the house. That's great in January, but less-than-great in July. You could say it's a downside of a basement install. Strike two is a family of 6 (DHW only :lol:). We are only 2 now with the kids grown and out of the house. Without storage, I've shut down the boiler many times in the shoulder season (when the need for heat is low), and have a really good understanding of how long the 40 gal Superstor will retain hot water. It can go 10-12 hours, but there's typically only one quick shower available (for me), and I know the boiler better be back online and have the SS recharged before my wife wants a shower. So, for a family of 6, you will have a very hard time running the boiler just once - you're likely to need a much more continuous supply of hot water to keep the tank up to temp. Strike three is the simple fact that after doing this for 6-7 months, you will be VERY happy to take a break for the Summer! I think that most of the folks who do DHW with a gasser in the Summer either have outside installs and/or have storage. Nofossil, one of the mods on this forum (and who is also a top tech), has a great solution for this - he runs a gasser with storage in the heating season, and then switches to solar for Summer DHW. You can certainly run the boiler a few times for DHW to get used to how it runs, but I doubt you will want to do that for very long.
 
I'd second that but no harm in having a go at it, at least while it's not too hot in the house yet. If you have a new boiler you want to try, see how it goes for a while. You probably will get tired of it after a while though.
I'm in the process of setting up my solar panels for summer dhw, I believe this to be the best solution.
Good luck
 
I got 3 years exp. running a Tarm gassifyer in basement w/HW storage. I find it is harder in summer to get a good blaze going when the boiler is cold, but I only have to do it every 4 to 5 days with the 620 gal. storage tank, so its worth it for me. Its much easier to maintain good gasification when the boiler is warm, rarely a problem during heating season. Running a gassifyer with storage is great, it just runs flat out until the wood is gone.

New to the site, my 2 sense.
 
The heat off the boiler in the basement would be to much in the summer. And like said once the boiler got up to temp and burning good it would be time to shut it down. I wouldn't be afraid to have well insulated storage in the basement with the boiler outside to use in the summer. I have very little heat loss off my storage. You would need a much larger super store and or storage,
with the boiler outside for summer use.
 
Thanks for the information guys. I appreciate it. I have been looking around for a used tank of some sort. Two of the same kind of smaller ones would be easier for me to get into the basement. Put them one above the other and then insulate them myself. Work is picking up which is resulting in some overtime for us. Maybe I will be able to afford the storage if I can find the right tank or tanks used. Let me ask you this. Is there anything special they need to be. I need them to be clean, no leaks of course, and able to withstand the temperature and light pressure. So I guess it would need to be carbon steel or stainless steel. Is that correct? And is there anything else I need to consider? Being able to get it in the house is always a good thing. Can some of you guys with storage and maybe some who have built your own storage give me some suggestions? Thanks.
 
This is my second season with my Wood Gun and I think I'll be heating my hot water longer this year than last, but i won't be running it after next month. Mine is also in the basement and while it's true that residual heat loss will migrate upwards to the living room I also will have my basement windows and entry door open to allow ventilation and some heat loss that way. So, for us this works until it gets really warm out since we are only a 2 person household and the 60 gallons onboard storage gives us enough hot water for 3+ showers(initial showers are early in the day while boiler is running), dishes and a load or two of laundry. 6 people and a dishwasher may/will be entirely different!

I am surprised how long the WG will keep it's water above 160 degrees with no call for heat. Yesterday wife had shut off the boiler early afternoon(I'm assuming it was around 180 at that time) and I checked the temp just prior to my evening shower after splitting some wood. Before running the shower and doing the evening dishes the temp was just above 160...when dises and shower done it had dropped less than 10 degrees.

As stated...give it a shot and see how it works for you. I completely undrestand not wanting to use oil for DHW...that's expensive!
 
Gassifyer, the primary cost in a storage tank is likely to be the copper. My 620 has 2 - 120 feet long heat exchange coils and a 180 foot long domestic HW coil. Thats alot of copper at $3.50 a pound. There is a good picture of a HW storage tank at http://www.health.state.ny.us/environmental/outdoors/air/owb/definitions.htm#hswt. Best advice I can give you is that HW storage is great, light a fire and walk away until next time, doesn't matter if its dead of winter, summer or the shoulder months.

Sorry for the delayed response. Went fishing this past weekend. Got a 21" splake on a fly rod, awesome.
 
Would there be anything wrong with just an insulated tank that stores the hot water from the boiler? That water would then pass through my in-direct hot water heater, which is a s.s. tank within a carbon steel tank, and heats the domestic hot water like that. No copper coils needed. My oil fired boiler heats this hot water tank now, and it does a great job of supplying us hot water. I went down and took a closer look at my hot water heater tank. Then did some research on the internet of how it works. I then remembered when the guy installed my boiler that he told me to go with one that has no coil, chance that my well water could build up deposits and block the coil, then we also decided to go with this tank within a tank water heater for the same reason. What do you think?
 
That DHW tank is a Triangle Tube Phase III Smart 40. Actually holds 36 gallons. The Smart series tank is a nice tank. We have had it for 7 years now I guess. The time goes by quick. The oil boiler can heat the water so fast through that tank within a tank system that we can take six showers straight and it does not run out. I am thinking a 200 to 250 gallon pressurized and insulated storage tank would work great with the wood gun and this hot water heater/tank. What do you guys think?
 
Maybe someone else has experience with having the boiler and the storage tank be the same reservoir, but I don't. I do know that the storage tank is sized to the boiler rating. For instance, my Excel 2000 is rated at 102,000 btu output and was properly sized with a 620 gallon storage. I can run a full load of wood (4 cu. ft. firebox) with the tank starting at 120 F and with no draw from the house, the tank ight get up in the 170s. A 200,000 btu output boiler would need a 1200 gallon tank, etc. I just don't know the pitfalls of configuring the system the way you are suggesting. The nice thing about a prefabricated tank is they are relatively easy to get into the basement (they are shipped flat), they are relatively easy to assemble and they are really well insulated. You can barely detect any heat loss even when the tank is at 170.
 
No, the boiler and the thermal storage tank would not be the same resevior. I guess I did not explain that correctly. My boiler and the storage tank would be the same as yours. I would be going with a pressurized tank. I was just talking about the DHW heater having a tank inside a tank system. The hot water from the boiler, or the thermal storage tank, would circulate through the hot water heater to heat my DHW. That is how my DHW tank works. Instead of a coil it uses a s.s. tank inside of a cabon steel tank. Good heat transfer system. Thanks for the info, sounds like the ash works well for you. You must be talking 4 full cord. If you get through winter with 4 face cord, I want your system. :ahhh:
 
I had a boilermate DHW tank, similar to what you have. I did away with it and get my DHW from a coil in the 620 gal tank. Its nice because in the summer I only need a fire every 4 to 5 days. I didn't mean to imply that I only burned 4 cords of wood a year. The firebox on the Tarm is 4 cubic feet. I burned 6 and a half cords so far this year since Oct.1. Just had an energy audit done and the equivalent heating value would have required about 1200 gallons of oil to heat this 2900 sq. ft. house and the basement, so it is pretty efficient. 1 cord = 200 gallons of oil.

I got a friend who has a standby oil boiler and a DHW tank that is plumbed so that he can either use the tank coil with wood or bypass the wood heater/storage tank and run on oil to heat the DHW tank. Its more money, but the coil in the storage tank is probably the most efficient if you plan to use wood to heat DHW during the summer.
 
I have the boiler in a shed and 2x500 propane in the basement. I have an in-tank HX in the top propane which I use for DHW, works fine, and if the temp is not up to what I want the Rennai boosts it the rest of the way. I will probably burn this summer to save on propane - one fire a week or so. Tank is insulated in the basement - heat loss helps keep the humidity lower in the basement. You may try looking for two 2 x 250 propane tanks - should be able to fit them in the house. You could even start with one and then add more as $ and time permits.
 
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