airplanes20 said:
Does anyone have a Tarm boiler Model Solo Plus 40 without storage tanks. I was wondering how long of a burn time you get during the winter months?
Also wondering how long people with Solo Plus get out of a burn with the pressurized 440 gallon storage tanks. Im trying to figure out which way to go, its another 5000 for the storage tanks.
Anyone with information on the newer Solo Plus boilers would be great. Can't always believe the ratings from the boiler company.
I live in Central NH and have a 3000 sq house, it is well insulated.
If you were going with the thermal storage right out of the gate, I would recommend that you opt for the Solo Innova boiler. In my opinion, draft induction is one of the nicest features you can have on a wood boiler. If your home is indeed well insulated, you could perhaps purchase the Solo Innova 30 and 440 gallons of storage to get the job done, and also save a few bucks on the innova over the solo plus 40... actually about a grand.
If you do much reading on this sight, you will find that burn time (without storage) is effected by several factors, including heat load, wood species and moisture content, and of course firebox size. You will also find that as you oversize the firebox to gain burn time, you lose efficiency because of an increased percentage of your heat load being satisfied by the inefficient combustion of the upper chamber as opposed to the very efficient secondary combustion. It is desirable to size the boiler as small as possible, but there is a delicate balance between burn time and efficiency. We used an oversized gasifier without storage here for a season before adding thermal storage and ultimately upgrading to a Froling FHG-L. All I can say is that a gasifier without storage works pretty well as far as fuel usage goes... but comparing it to a gasifier with storage is like comparing night and day with regards to ease of operation. And of course, the Froling really is a cut above the rest in sophistication.
Your cycle time, or time between firings, on a boiler with thermal storage can vary greatly. I don't know what your heat load is, but lets say perhaps a solo-innova 30 with 440 gallons of storage could offer you 12 hour cycles at peak load with no more than 8 hours of burn time to charge the tank. (note that when I say "peak" load, I actually mean a 12 hour average load at design temps) Every evening that you were at peak load, you would light, load, and load before bed one more time in order to wake up in the morning with a few coals for a morning firing. Your daytime average heat load would most likely be less because of solar gains, so you might only need to fire once in the morning. During the coldest part of the year, you might be loading as much as if you didn't have storage, but come the shoulder season, the benefits of thermal storage would be very real, and very worth the extra investment... a clean boiler, a clean chimney, fewer firings, less or perhaps no concern with "burn time," less fuel usage, DHW all summer, etc.
Of course, you also have to take into consideration what type of emitters you are using when choosing to go with storage or not... high temp emitters like baseboard do not provide much delta T, and therefore you get fewer usable btus out of your storage. Radiant panels or radiant floor heat offer the highest delta t, and therefore are useful for getting the longest cycle times out of your storage.
At any rate, there is a lot to consider... take your time, read the forum, and consider your options carefully. If you can swing the extra expense of thermal storage, you will NOT be sorry. If you would rather stage your installation over a few years, then the solo plus will work nicely until you can spring for the thermal storage later, at which time your solo plus will seem like a different animal altogether. Either way is kind of a win-win... but like I said earlier, the draft induction and the smoke extraction passage on the innova are pretty nice features.
cheers
