A Month With The Tarm

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
Status
Not open for further replies.
AroostookDave

AroostookDave

Member
Apr 24, 2011
51
Aroostook River Maine
Having used a standard Kerr wood boiler for 32 years, my observations on using a gasification boiler:

- Much easier to get heat and hot water - no putting in wood every half hour, getting cold overnight, no smoke from the firebox. Because of the induced draft fan, having the firebox door open for loading is not a problem. You can see the flame being sucked into the ceramic tunnel.
- Less wood usage, by this time last year I would have been further into the woodshed
- No hot water pumped into the cellar zone on overheating - goes to the water storage
- This time of year one heating per day does the job, I'm guessing that January/February will take 2 heatings. In the September warm spell we went 5 days with one firing. This bodes well for next summer.
- My wife and daughter have run the system and like it - they were reluctant to tend the Kerr because of smoke.
- The oil furnace backup has not been needed at all so far
- Cleaned it per the instructions a couple of days ago. The 12 tubes were not difficult to clean. The only pain was checking the 10 metal aprons in the firebox. Manual recommends monthly cleaning of the aprons, but there was no creosote or buildup of ashes behind, no vent blockage. They are heavy and not easy to move, so I won't do that again for a while.
- Even though we have baseboard heating, there has been no problem with house heating
- It seems to be difficult to get the water tank temperature above the 170s, but that has been OK.

Gasification has been what I hoped it would be - so far. :)
 
I ran an EKO40 for 4 years without storage and am still trying to get it back on line (long story). Even without storage it beat my wood furnace hands down for output and being more fuel conservative. The cleaning thing may be more needful if the wood moisture gets too high. I seldom had more than fly-ash at the top of my heat tubes even while operating in idling mode.
 
Glad to hear it is working out well for you Aroostookdave! Got any pictures of your system? I started a thread of pics of our boiler systems. If you want to add them here is the link. https://www.hearth.com/econtent/index.php/forums/viewthread/82626/

Have a good one man. And keep us posted on how things are going. Sooner or later it is actually going to get colder.
 
Very nice. I do remember seeing that thread now. How is it working for you? Much demand for heat yet?
 
It seems to be difficult to get the water tank temperature above the 170s ...
Click to expand...

My Tarm Solo 40 has a hi-limit shutdown of the draft fan at about 185F, actual is a little higher, and it varies some also, sometimes going as high as 190F. Is yours the same? If so, achieving about a 10F approach temp to your boiler output (185F boiler and 175F tank) with open storage and coil heat exchanger probably is about the best you can do.

Glad your Tarm system is working well for you.
 
jebatty said:
It seems to be difficult to get the water tank temperature above the 170s ...
Click to expand...

My Tarm Solo 40 has a hi-limit shutdown of the draft fan at about 185F, actual is a little higher, and it varies some also, sometimes going as high as 190F. Is yours the same? If so, achieving about a 10F approach temp to your boiler output (185F boiler and 175F tank) with open storage and coil heat exchanger probably is about the best you can do.
Glad your Tarm system is working well for you.
Click to expand...
I only know about other boilers from I read on this forum, so there must be something I'm not understanding about what you wrote, Jim. My Econoburn has a PLC which allows lots of things to be changed - hi setpoing, diff, etc. I've always assumed that other gassers also have a comparable PLC to allow run chacteristics to be modified. But even if it only has a simple aquastat, I was expecting the answer to the OP's question to be, just move the hi setpoint of the boiler up. But your post makes it sound like the Tarm doesn't go above 190*. So what am I not understanding about your answer?
 
jebatty said:
It seems to be difficult to get the water tank temperature above the 170s ...
Click to expand...

My Tarm Solo 40 has a hi-limit shutdown of the draft fan at about 185F, actual is a little higher, and it varies some also, sometimes going as high as 190F. Is yours the same? If so, achieving about a 10F approach temp to your boiler output (185F boiler and 175F tank) with open storage and coil heat exchanger probably is about the best you can do.

Glad your Tarm system is working well for you.
Click to expand...

The Operating Thermostat (probably the same thing) which shuts off the draft fan has a setting between about 190 and 204 degrees. I have it set to the higher number. When I see the boiler temp getting close to that I don't add wood until it comes down a bit. The Thermostat has shut the fan off a few times, but it turns back on within 10-20 minutes. I agree that the closer the tank gets to the high limit of the boiler the harder it will be to increase the water temp. Living with high 170s to 180 is fine. At that temp the tank has plenty of heat reserve.

willworkforwood...I could try playing with the aquastats but not being a heating/plumbing specialist I will limit my experiments to the setting limits in the Tarm manual. As mentioned above, I'm getting plenty of heat and I don't want to mess with what seems to be working.
 
AroostookDave said:
jebatty said:
It seems to be difficult to get the water tank temperature above the 170s ...
Click to expand...

My Tarm Solo 40 has a hi-limit shutdown of the draft fan at about 185F, actual is a little higher, and it varies some also, sometimes going as high as 190F. Is yours the same? If so, achieving about a 10F approach temp to your boiler output (185F boiler and 175F tank) with open storage and coil heat exchanger probably is about the best you can do.

Glad your Tarm system is working well for you.
Click to expand...

The Operating Thermostat (probably the same thing) which shuts off the draft fan has a setting between about 190 and 204 degrees. I have it set to the higher number. When I see the boiler temp getting close to that I don't add wood until it comes down a bit. The Thermostat has shut the fan off a few times, but it turns back on within 10-20 minutes. I agree that the closer the tank gets to the high limit of the boiler the harder it will be to increase the water temp. Living with high 170s to 180 is fine. At that temp the tank has plenty of heat reserve.

willworkforwood...I could try playing with the aquastats but not being a heating/plumbing specialist I will limit my experiments to the setting limits in the Tarm manual. As mentioned above, I'm getting plenty of heat and I don't want to mess with what seems to be working.
Click to expand...



My Econoburn will do that at times, my thought was to add another small pump in parallel that is controlled by the aqua-stat. Before the high limit is reached start pumping more water due to the lower delta t.

What do you think? Would that help push storage temps higher without idling?

gg
 
That tank you'll not push it above 183 or 185. I have A Innova 30 with that same tank, and i'm quite sure the same HX's. It's an unpressurized tank. You can achieve a solid 180 on top and mid 170's? middle and 160's? bottom but that takes a bit of wood, and a fair bit of idling to go higher. For me, just getting the top in the high 170's pushing 180's works real good. Not worth the time or wood to drive up the tank any higher. but i would put these HX's up against any other unpressurized vessel. Those will drive the tank up into the 160's/170's in no time. And will extract all the useable heat once the fires out. The DHW HX--I can take a comfortable shower when the tank is down to 110's+/-


In the summer i only go about 160's on top.
 
flyingcow said:
That tank you'll not push it above 183 or 185. I have A Innova 30 with that same tank, and i'm quite sure the same HX's. It's an unpressurized tank. You can achieve a solid 180 on top and mid 170's? middle and 160's? bottom but that takes a bit of wood, and a fair bit of idling to go higher. For me, just getting the top in the high 170's pushing 180's works real good. Not worth the time or wood to drive up the tank any higher. but i would put these HX's up against any other unpressurized vessel. Those will drive the tank up into the 160's/170's in no time. And will extract all the useable heat once the fires out. The DHW HX--I can take a comfortable shower when the tank is down to 110's+/-


In the summer i only go about 160's on top.
Click to expand...

FlyingCow, you have almost the same setup, I am sure the same HX and DHWX. I have a thermometer probe in the top water layer, and another in the bottom layer. They have not been more than 5 degrees apart. I appreciate hearing of your experience with the temps. Those copper HXs were expensive, but well worth it in the long run, I'm sure. Ladies here have been very happy with the hot water temps, even when the top of the tank reads in the high 120s. I have not tried using temps lower than that yet. You are right, the tank water temp goes up nicely when heating. It is surprising how slowly the water temp goes down, even when heating the house.
The DHW use hardly registers heat usage - showers, laundry, dishes take only a few degrees in a day. Like you, in warm weather I won't push the heat up as high.
 
willworkforwood said:
jebatty said:
It seems to be difficult to get the water tank temperature above the 170s ...
Click to expand...

My Tarm Solo 40 has a hi-limit shutdown of the draft fan at about 185F, actual is a little higher, and it varies some also, sometimes going as high as 190F. Is yours the same? If so, achieving about a 10F approach temp to your boiler output (185F boiler and 175F tank) with open storage and coil heat exchanger probably is about the best you can do.
Glad your Tarm system is working well for you.
Click to expand...
I only know about other boilers from I read on this forum, so there must be something I'm not understanding about what you wrote, Jim. My Econoburn has a PLC which allows lots of things to be changed - hi setpoing, diff, etc. I've always assumed that other gassers also have a comparable PLC to allow run chacteristics to be modified. But even if it only has a simple aquastat, I was expecting the answer to the OP's question to be, just move the hi setpoint of the boiler up. But your post makes it sound like the Tarm doesn't go above 190*. So what am I not understanding about your answer?
Click to expand...

My Solo 40 of 5 years ago probably is primitive compared to many gassers now available. OK to substitute operating thermostat for hi-limit. My comment is accurate for my Solo 40. The main point of what I didn't say very well is that achieving a 10F approach temp with open storage probably is about as good as is reasonably possible. Yes, turn the operating thermostat up, but the tank likely will always be about 10F +/- lower than the highest boiler output temperature. Closer approach temps are possible with "over-sized" hx's, but at an ever increasing cost. Coil or plate hx, the answer still is the same.
 
jebatty said:
... Yes, turn the operating thermostat up, but the tank likely will always be about 10F +/- lower than the highest boiler output temperature. Closer approach temps are possible with "over-sized" hx's, but at an ever increasing cost. Coil or plate hx, the answer still is the same.
Click to expand...
Yep, that clarifies your previous post - thanks.
 
Status
Not open for further replies.

Similar threads

JTWALL
Eko Model 25 Gasification Issue
Replies
5
Views
1K
The Boiler Room - Wood Boilers and Furnaces
Triumph562
T
L
Seton W-90-E Wood Boiler Serial 01211 built at the time by Bethel Engineering & Equipment at the time.
Replies
10
Views
1K
The Boiler Room - Wood Boilers and Furnaces
snowman49820
snowman49820
P
Dodging a bullet with my heating system
Replies
0
Views
955
The Boiler Room - Wood Boilers and Furnaces
peakbagger
P
M
Firebrick for Tarm Solo Plus MK-II
Replies
6
Views
822
The Boiler Room - Wood Boilers and Furnaces
pettibone
P
K
Wood furnace warped - worth/safe to repair?
Replies
6
Views
603
The Boiler Room - Wood Boilers and Furnaces
johneh
johneh
Top Bottom
Back