First big chill down of this season, -19F forecast for tonight. High today 0F, which it is right now (9:05am). Got a jump on charging 1000 gallon storage yesterday afternoon, and topped it off this morning, which should last until Monday.
Chillin' -- Charge!
- Thread starter jebatty
- Start date
-
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
maple1
Minister of Fire
looks like the cold will be arriving here tomorrow night with a low of 10 F. It made it up to 48 today, unseasonably warm for this time of year. I took advantage of it and worked outside all day. Appears the cold is going to be here to stay for a while this time.
maple1
Minister of Fire
Jim, did you have to modify your Tarm Solo Plus to allow you to heat your storage up to 195 degrees (or are you practicing some sort of boiler voodoo)? When my Tarm Solo Innova gets storage up near 180 degrees the induced draft fan shuts off and the boiler starts idling. Very frustrating.
Mike
Mike
Last edited:
It is the end of burn. Notice stack temp of 132F; also radiant is "off." When the radiant circulator is "on," radiant supply is about 100F via a mixing valve which mixes down the tank temperature.
No voodoo (well maybe a little). The Solo Plus 40 has an operating thermostat knob on the front panel which provides a small range of adjustment on output supply temp before the draft fan shuts down. The manual says the minimum is 180F and the maximum is 190F. I have found that when the boiler is operating and the boiler circulator is "on," such as when charging storage, the actual output supply temp is higher than the thermometer reading on the front panel. My circulator moves about 14gpm through the boiler, and I suspect the water flow route through the boiler quickly moves the hottest water out the supply and slightly cooler water remains at the top of the boiler where the operating thermostat sensor is located. Anyway, I can get actual supply output up to about 196-197F before the draft fan will shut down, and at this temp the thermometer reading on the front panel will be about 192-193F.
The voodoo is that if I want to charge storage to the level shown on the monitoring panel, I have to use a weighed wood burn to ensure the wood load is quickly burning down as supply temp rises so that boiler btuh output is not greater than can be absorbed by storage. In other words, as supply temp rises to 190F+, return temp from storage also will be rising to a difference less than 20F. As the picture of the monitoring panel shows, bottom of tank is 188F and top of tank is 195F, which meant that before the boiler shut down supply to the top of tank was 195F. Delta-t was 7F, which at 14gpm is moving only 49,000 btuh, which also means that the fire was quickly dying out to low coals.
Had I not done a weighed wood burn, I easily could have had too much wood in the boiler which would supply more btus than could be moved to storage, and the boiler would have idled. There was no idling in this near maximum charge to my storage tank in this burn.
I also have the draft fan lo-limit (end of burn shut down) thermostat set to about 105C (220F). This is a dial thermostat under the top cover of the boiler. As the fire burns down to coals and stack temp as measured by the lo-limit sensor drops to this point, the draft fan shuts off. This setting results in some un-burned coals being left in the firebox which aids a quick start on the next fire.
The reason I asked is because my garn Jr. In my shop temp. Is 194* after my burn and I have 72' of insulated line down over 48", going into the basement. The temp of my water there is only 150* and I can't figure out where the other 40* went?
I believe I have a 50 plate hx with a taco 007 circulating at the boiler and I'm pulling with a wilo pump in the basement. Everything seems to work fine.
The garn draws from about 4" or so from the top of the boiler and I put a thermometer in the top so I know that reading is accurate and I have two thermometers downstairs both reading 150*, help!
I believe I have a 50 plate hx with a taco 007 circulating at the boiler and I'm pulling with a wilo pump in the basement. Everything seems to work fine.
The garn draws from about 4" or so from the top of the boiler and I put a thermometer in the top so I know that reading is accurate and I have two thermometers downstairs both reading 150*, help!
That much heat loss also would concern me. Without more detail, a 50 plate hx may have a 10F temp drop between Sides A and B, which is fairly "normal," although a plate hx may be sized to provide a closer approach temp. That still leaves a 30F temp loss. Assuming your thermometers are accurate, two things come to mind. You have inadequate insulation and/or you may have water penetration into your insulated 72' line, and water can absorb, move and dissipate heat quickly.
maple1
Minister of Fire
More temp measurements might help. All 4 temps at the HX (in & out both sides). In & out of both lines of underground. Your HX pumping could be mis-matched? Could be loss undergound?
Jim, thanks for your reply. Our Tarm boilers seem to have similar dials and settings so I will try to replicate your results and monitor my temps more effectively. I am going to start weighing my wood too since I am constantly over or undershooting the amount of wood needed for each load. I have a thread going over in the Woodshed now on how best to weigh a wheelbarrow full. I started that thread after rereading one of your older threads I'd saved on wood weighing.
By the way, how do you weigh your firewood?. You posed that question in your older thread but I didn't see any replies. I liked a suggestion I got from Saskwoodcutter to use three bathroom scales to weigh a wheelbarrow load. Simple, inelegant, and undoubtedly effeciive.
Mike
Last edited:
I got a digital luggage scale (about $10), built a rack to hang from the scale, then loaded the wood into the rack, and noted the weight. I'm sure there are easier ways, but after awhile doing this, and knowing your wood, in short order you can eyeball weight based on volume quite closely. And if you don't try to truly max your storage, but leave a little room for error, then eyeballing works very well.
- Status
Similar threads
