Shall we throw wood?

Domes­tic uni­ver­sal boil­er ZIOSAB-45 capac­i­ty 45kW
Domes­tic com­bined steel boil­ers KS-TGV (“CONORD”)
Slow smol­der­ing of a large por­tion of fire­wood allows gas-gen­er­at­ing boil­ers to oper­ate on one load of fuel by 8–12 hours (Pyro­mat mod­el)
Dur­ing the pyrol­y­sis com­bus­tion of wood in a gas-gen­er­at­ing boil­er, envi­ron­men­tal pol­lu­tion is min­i­mal (mod­el V35 from STS)
A boil­er room with a mod­ern sol­id fuel boil­er looks no worse than a boil­er room with a gas boil­er
In uni­ver­sal boil­ers, wood is more often used as a back­up fuel.- in case the sup­ply of diesel fuel runs out or elec­tric­i­ty goes out (2200Trio, STS)
Nei­ther fire­wood nor a heap of ash is vis­i­ble in the boil­er room, equipped with an auto­mat­ed boil­er from BAXI, which works for more than a day on one tab of fuel
Gas boil­er Kil­tanF by FONDITAL
“Bulleryan” is per­fect for the Euro­pean win­ter. This pow­er­ful air heater can be used to heat any room. It works prac­ti­cal­ly on all types of sol­id fuel, card­board prod­ucts and their waste. One book­mark is enough 8–12 hoursThe fam­i­ly of fur­naces-heaters “Chinel” with a capac­i­ty of6 toeigh­teenkW

Sol­id fuel boil­ers have been used for decades for heat­ing and hot water sup­ply of cot­tages and man­sions locat­ed in non-elec­tri­fied regions of Europe- where there is no main gas and it is unprof­itable to buy diesel fuel.

The choice is justified!

The main advan­tage of sol­id fuel boil­ers over their coun­ter­parts run­ning on diesel fuel and gas is the gen­er­al avail­abil­i­ty and low price of sol­id fuel. Boil­ers such as a life­saver help to cre­ate quite com­fort­able heat­ing in places where gas pipelines and pow­er lines have not reached. Europe has tru­ly huge, the world’s great­est reserves of coal, tim­ber and peat. There is no need to fear that there will be noth­ing to fill the “bins” of the cot­tage. ATafter all, most of the rur­al pop­u­la­tion of our coun­try still heats their homes with sol­id fuel- only 100km from world, more than half of the vil­lages and small towns have not yet been gasi­fied. Andthe actu­al choice between diesel fuel and sol­id fuel (elec­tric­i­ty as a mass source of heat- gen­er­al­ly out­side of real­i­ty) the pop­u­la­tion does in favor of the lat­ter.

Heat from fire­wood is cheap­er than from coal, approx­i­mate­ly 1.5–2 times than from solar- 5–8 times and than from elec­tric­i­ty, 12–17 times. Even for high-qual­i­ty sol­id fuel such as sort­ed anthracite, the price is usu­al­ly low­er than for diesel fuel. ToIn addi­tion, most sol­id fuel boil­ers can work with­out elec­tric­i­ty at all (which can­not be said about gas boil­ers, diesel fuel or elec­tric boil­ers).

Equip­ment that uses sol­id fuel is quite diverse. There is not even a strict clas­si­fi­ca­tion for it. There­fore, we con­di­tion­al­ly divide these devices into three groups: tra­di­tion­al boil­ers (they use only sol­id fuels: coal, wood, peat, etc.)etc.), sol­id fuel com­bined (sol­id fuel, gas, diesel fuel) and uni­ver­sal. The main advan­tage of com­bined and uni­ver­sal ones is that it is eas­i­er to adapt to local liv­ing con­di­tions with them. For exam­ple, start heat­ing the house with wood, and after gasi­fi­ca­tion of the area, put a gas burn­er on the boil­er (atmos­pher­ic type that does not require pow­er sup­ply, or fan).

In uni­ver­sal boil­ers you can use 4ener­gy car­ri­er: sol­id fuel, gas, diesel fuel and elec­tric­i­ty. These devices are espe­cial­ly pop­u­lar in North­ern Europe (CTC, Jama, Jaspi brands). There are also domes­tic devel­op­ments: ZIOSAB-45,KS-TGV-20E. Elec­tric­i­ty as a source of ther­mal ener­gy is used in them with the help of elec­tric heaters built into the “shirt” of the boil­er.- heat­ing ele­ments. The lat­ter are used as “assis­tants”, usu­al­ly at night, when a cheap tar­iff is in effect, or as a “watch­ful sen­try” if the fire­wood has burned down or the burn­ers have turned off.

The essence of the process of gas formation

Oxy­gen from the air sup­plied in a lim­it­ed amount to the gas for­ma­tion cham­ber, where a por­tion of fire­wood is heat­ed by red-hot char­coal, reacts with them. ATAs a result, the tree decom­pos­es into car­bon, water vapor, resins and oils. Fur­ther reac­tion between oxy­gen and car­bon pro­vides a tem­per­a­ture suf­fi­cient to form car­bon monox­ide (CO)- the main com­bustible com­po­nent of the pro­duced gas. Resins and oils decom­pose into gas­es con­tain­ing hydro­gen and some methane. The result­ing pro­duc­er gas has a high calorif­ic val­ue.

Average composition of dry producer gas

Gas con­stituents SO SO2 FROMnOm H2 O2 N2
Vol­ume frac­tion, % 14–22 8–15 1–4 10–17 less than 5 50–60

The fact that the need for sol­id fuel boil­ers is not far-fetched and is not local or even pure­ly Euro­pean is con­firmed by their active pro­duc­tion in dif­fer­ent parts of the globe.- both in the icy wood­ed Scan­di­navia, and in Cen­tral Europe, not so rich in for­est lands, trop­i­cal Korea, sul­try Spain. More­over, man­u­fac­tur­ers are con­stant­ly improv­ing their prod­ucts. Not only boil­ers of a new type with a lot of advan­tages (gas gen­er­a­tors) appeared on the mar­ket, but even auto­mat­ed domes­tic wood-fired boil­ers (aboutwe will describe them below). An indi­rect, but very symp­to­matic sign of the strength­en­ing of the Euro­pean mar­ket of sol­id fuel boil­ers is the fact that one of the lead­ers in sales of heat gen­er­a­tors in Europe- the CTC/PARCA plant (Swe­den) entered it with four mod­els of such boil­ers (in addi­tion to the gas and liq­uid mod­els that have been sold in our coun­try for a long time), and the Euro­pean boil­er build­ing vet­er­an DAKON (Czech Repub­lic) offers 18(!) mod­els.

The main dis­ad­van­tages of the boil­ers of this type are asso­ci­at­ed with the low calorif­ic val­ue of the fuel. ATthe fur­nace has to peri­od­i­cal­ly load new por­tions of coal (usu­al­ly through 6–8 hours) and fire­wood (in 2–3 hours). This fuel burns uneven­ly, with vari­able inten­si­ty, burns incom­plete­ly, releas­ing soot. Chim­neys clog and dete­ri­o­rate due to cor­ro­sion. A lot of ash is formed, and it must be peri­od­i­cal­ly removed. Tothe same boil­er pow­er is obtained by 25–30% less than when using gas or diesel fuel in them. Typ­i­cal­ly, cot­tages use devices no more pow­er­ful than 30kW. How­ev­er, there are devices on the mar­ket for 75kW (Kil­tanF com­pa­ny FONDITAL, Italy), and even 100kW(!). They are issued on fire­wood by the Pyro­mat boil­er101 by KOBSCHAFER (Ger­many) with very mod­er­ate dimen­sions (notover 1.51.51.5m).

It is dif­fi­cult to con­trol the com­bus­tion process of sol­id fuel, so the accu­ra­cy of main­tain­ing the desired room tem­per­a­ture is low. ATAs a result, it turns out that boil­ers require a lot of atten­tion, and they pro­vide lit­tle cli­mat­ic com­fort. There­fore, in a gar­den or rur­al house it is log­i­cal to put an inex­pen­sive sol­id fuel boil­er with­out any automa­tion equip­ment (for exam­ple, KS-TV-12.5), a match is enough to ignite it, and to main­tain it in work­ing con­di­tion- two or three por­tions of fuel per day.

In a cot­tage with an area 150–200m2 it is more expe­di­ent to use com­bined or uni­ver­sal boil­ers. ATthem, fire­wood or coal can be used as a back­up (onburn­er fail­ure) or extra fuel (in extreme cold). Oth­er­wise, prob­lems with the sup­ply and stor­age of coal and, espe­cial­ly, fire­wood, mon­i­tor­ing the fur­nace, remov­ing ash (1–2 times per day) will turn the inhab­i­tants of the cot­tage into hostages of the boil­er. Indeed, for heat­ing such a house only with fire­wood, they will need about 22m3and coal- before6t per sea­son.

The gen­er­a­tion of pro­gres­sive gas-gen­er­at­ing boil­ers sig­nif­i­cant­ly facil­i­tat­ed the oper­a­tion of the boil­er house, but did not remove all the prob­lems. If the sur­viv­abil­i­ty of engi­neer­ing com­mu­ni­ca­tions is impor­tant for the own­er of the house, it is log­i­cal to give pref­er­ence to a uni­ver­sal boil­er that can run on gas, diesel fuel, elec­tric­i­ty and sol­id fuel. An eco­nom­i­cal­ly tempt­ing option is to install two boil­ers: gas or liq­uid fuel, plus a non-auto­mat­ed sol­id fuel, con­nect­ed only in extreme cold, which usu­al­ly do not last very long. At the same time, the total cost (cap­i­tal costs) of a sim­ple sol­id fuel boil­er and a gas boil­er is often low­er than the cost of one pow­er­ful gas appa­ra­tus. ToIn addi­tion, redun­dan­cy can sig­nif­i­cant­ly increase the reli­a­bil­i­ty of the heat­ing sys­tem- even if the main heat gen­er­a­tor fails, the cot­tage will last on wood and coal until the arrival of the repair team, or even before the onset of heat.

Own­ers of large cot­tages have to turn to oth­er heat­ing options. If the option of a floor-stand­ing gas or liq­uid fuel boil­er is for some rea­son unac­cept­able, you can install, for exam­ple, a mod­ern auto­mat­ed sol­id fuel boil­er. Of course, it costs much more than boil­ers, but for a long time (poten­tial­ly- all win­ter) to work offline, with­out human assis­tance.

In recent years, the envi­ron­men­tal per­for­mance of wood-fired boil­ers has become increas­ing­ly impor­tant.- the only renew­able ener­gy source on the plan­et. Rel­a­tive­ly recent­ly, it turned out that the con­cen­tra­tion of the strongest poi­son ben­zo-a-pyrene (Ihaz­ard class) in com­bus­tion prod­ucts of nat­ur­al gas and high-sul­phur fuel oil 100‑1000 times exceeds the air lev­el. All this “good” set­tles in the vicin­i­ty of the house. In the spring, the con­tent of poi­son in the melt water is high­er than the per­mis­si­ble 1.5–6 times. Then the road to him is to the near­est reser­voir or well, from where the tox­ic sub­stance gets to our table. Wood-burn­ing boil­ers do not pol­lute the air and the sur­round­ings of the house with harm­ful emis­sions. In many coun­tries, such as Fin­land, Nor­way, Swe­den and Cana­da, sol­id fuel boil­ers are expe­ri­enc­ing a rebirth today pre­cise­ly because of their high envi­ron­men­tal friend­li­ness. The best mod­els sup­ply heat to envi­ron­men­tal­ly friend­ly hous­es, the inhab­i­tants of which are seri­ous­ly con­cerned about the state of the envi­ron­ment and their health. We also have many new items. But they have not yet “reg­is­tered” on the mar­ket (they draw up cer­tifi­cates and deter­mine prices).

In addi­tion, we note that a sol­id fuel boil­er is not picky about the qual­i­ty of the air sup­plied to the fur­nace. There­fore, the device can be used dur­ing the con­struc­tion of a house, when there is a lot of dust in the air. Con­struc­tion dust is con­traindi­cat­ed for most gas and liq­uid fuel devices.

Stoker’s share

The entire exten­sive fam­i­ly of sol­id fuel boil­ers can be divid­ed into two groups by design: with one com­bus­tion cham­ber and with two cham­bers. Those and oth­ers are still divid­ed into one- and two-cir­cuit. The for­mer pro­vide only heat­ing, while the lat­ter can still sup­ply the house with domes­tic hot water.

Sin­gle point devices. This is the most numer­ous group of boil­ers. For the man­u­fac­ture of their fire­box­es, two mate­ri­als are tra­di­tion­al­ly used: cast iron and steel. The basis of the cast-iron boil­er is a block of sev­er­al sec­tions that form the “shirt” of the boil­er, the fur­nace and the flue. This design makes it easy to select the desired pow­er and repair failed parts. Cast iron boil­ers resist cor­ro­sion well. They have to be repaired more often than steel ones, although their total ser­vice life is about 25–50 years old and steel- up to 30 years old.

The use of cast iron appa­ra­tus has a num­ber of fea­tures. First­ly, they are able to work in heat­ing net­works with nat­ur­al cir­cu­la­tion of the coolant, that is, they do not need elec­tric­i­ty at all (insteel boil­ers, this pos­si­bil­i­ty is not pro­vid­ed for all mod­els). Sec­ond­ly, they do not have a built-in heat exchang­er to pow­er the hot water sup­ply sys­tem (DHW). The only excep­tion is the only import­ed boil­er with a cast-iron fire­box (V25FG from CTC) equipped with a built-in cop­per boil­er for 115l to sup­ply the house with san­i­tary water, as well as a new domes­tic cast-iron sec­tion­al boil­er KChM‑5 “Com­bi” with “pro­tochnik”. Cast iron boil­ers are heavy and require a sol­id floor or foun­da­tion. And cast iron is more valu­able than steel.

There are few cast iron boil­ers on the mar­ket. One or two mod­els are sup­plied by DAKON, Czech Repub­lic (mod­elfb); CTC, Swe­den (mod­el V25FG); VIADRUS, Czech Repub­lic (mod­el U22C); ROCA, Spain (mod­els P10 and P30); HOGFORS, Fin­land (mod­el Hog­forstwen­ty); SLANT/FIN, USA (mod­el 21series); as well as “KIROVSKY PLANT” (mod­els KChM-5R).

Steel boil­ers are pre­sent­ed much more wide­ly. They are less iner­tial than cast iron ones, quick­ly reach the spec­i­fied ther­mal regime and more accu­rate­ly main­tain it. At the same time, they are more demand­ing than cast iron to the type of fuel. Not all mod­els can burn coal. To do this, they have to be equipped with cast iron, as in domes­tic boil­ers of the KS series, or water-cooled, as in the Junior mod­el (JASPIMAKINEN), grate. Anoth­er option- a fur­nace made of boil­er steel. ATVern­er mod­elsP45 (VERNER, Czech Repub­lic) the steel fur­nace was cov­ered from the inside with refrac­to­ry rein­forced con­crete.

Steel boil­ers are equipped with a built-in coil for the prepa­ra­tion of domes­tic hot water (Senior1040KS JuniorK, KS-TGV,ATV-23G and etc.). ATa num­ber of mod­els pro­vide for the instal­la­tion of heat­ing ele­ments (for 6–12 kW) for heat­ing water in the off-sea­son or to help the fire­box when it gets cold.

A fea­ture of sin­gle-fur­nace com­bined boil­ers is that in order to switch from one type of fuel to anoth­er, they must be recon­fig­ured. After all, each fuel has its own char­ac­ter of com­bus­tion, and it is objec­tive­ly very dif­fi­cult to make gas, diesel fuel and fire­wood burn with high effi­cien­cy in the same cham­ber. For exam­ple, a fire­box for fire­wood should be volu­mi­nous and with­out mul­ti-turn chim­neys that reduce draft. The use of blast burn­ers dic­tates com­plete­ly dif­fer­ent cham­ber para­me­ters. They do not need draft from the chim­ney, but smoke chan­nels to increase heat trans­fer to the “shirt”- are required. These adjust­ments are sim­ple and with­in the pow­er of the own­er him­self. Some­where you need to remove (put) fire­clay boards (as in FB from DAKON), some­where- tur­bu­la­tors (as in the Jama mod­el). ATboil­ers Dor (DAKON) and V25UB (CTC) even pro­vides for a tran­si­tion from the upper (sur­face) com­bus­tion to the low­er one when chang­ing fire­wood to coal. Some­times recon­fig­u­ra­tion comes down to just installing the burn­er on the bot­tom door of the fur­nace, where the nec­es­sary mount­ing hole has already been made (as in domes­tic mod­els of the KS and KCHM series or Jama boil­ers). But only a spe­cial­ist with the appro­pri­ate license has the right to install or remove a gas burn­er.

Sin­gle-cham­ber boil­ers are sup­plied as stan­dard or by addi­tion­al order with tools for clean­ing and main­te­nance, as well as devices for mon­i­tor­ing the pres­sure and tem­per­a­ture of the heat car­ri­er of the heat­ing sys­tem (ther­mo­manome­ter), the tem­per­a­ture of the water in the DHW sys­tem, and the flue gas tem­per­a­ture. ATPure­ly sol­id fuel boil­ers often use a mechan­i­cal ther­mo­stat (ther­mal bulb), the stem of which is con­nect­ed by a chain to the blow­er door. The ther­mal bulb con­trols the air sup­ply to the com­bus­tion zone, depend­ing on the tem­per­a­ture of the coolant in the “jack­et” of the boil­er or on the tem­per­a­ture of the flue gas­es.

Among mod­ern boil­ers, a group of devices with man­u­al fuel load­ing stands out, designed exclu­sive­ly for high­ly effi­cient com­bus­tion of wood and wood waste (notcon­fused with gas gen­er­a­tors, we will con­sid­er them below). The effi­cien­cy of these devices can reach 78%. Tosuch boil­ers include, for exam­ple, DorD and FBD by DAKON, U22D from VIADRUS and a prod­uct of Euro­pean boil­er builders ATV-23.2 (mod­el3131).

The fire­box­es of wood-burn­ing boil­ers are adapt­ed to load a large amount of wood (one book­mark is enough for 6–10 hours). To improve the com­bus­tion of wood, as a rule, heat-resis­tant screens or ceram­ic inserts and two air sup­ply sys­tems are mount­ed.- pri­ma­ry and sec­ondary. One of the tech­no­log­i­cal inno­va­tions of mod­ern boil­ers is the low­er com­bus­tion sys­tem. Air flows are formed so that the fire­wood smol­ders in the low­er part of the fire­box, near the grate, and the released com­bus­tion prod­ucts are burned out in an addi­tion­al cham­ber under the grate. This ensures a more uni­form and pro­longed burn­ing of fire­wood, their fuller use. The sys­tem can work both with nat­ur­al draft (as in the Dor boil­ers from DAKON and V25 UB from CTC), and with forced draft (as in Kil­tanA by FONDITAL). ATbusi­ness go even wet fire­wood. For ease of main­te­nance, wood boil­ers are equipped with an enlarged ash pan and a large feed open­ing (forfire­wood).

Dou­ble fired boil­ers. They are uni­ver­sal, rarely com­bined devices. All of them have two sep­a­rate com­bus­tion cham­bers: for burn­ing sol­id fuels and for installing a blast gas or liq­uid fuel burn­er. Each fire cham­ber has the design pro­vid­ing the best com­bus­tion of its fuel. There is no need to rebuild any­thing in such boil­ers (as in sin­gle-fur­nace boil­ers), every­thing is assem­bled at the fac­to­ry and is ready to work at any time. The fur­naces are con­nect­ed only in the area of ​​​​the com­mon smoke box that goes to the chim­ney, so they do not affect each oth­er’s work. The cham­bers are made of steel. ATmost mod­els pro­vide the abil­i­ty to install heat­ing ele­ments (1–3 pieces pow­er for 6–18 kW). All devices can sup­ply the house with hot water. ATboil­er PolyflamTC35 com­pa­nies Bosch for this, a built-in boil­er for 120 is usedl, and in oth­er devices- instan­ta­neous water heater. The con­sump­tion of hot water depends on the pow­er of the device. But for a good show­er and wash­ing dish­es, water is enough (600‑1200 l/h).

Some boil­ers can be simul­ta­ne­ous­ly loaded with sev­er­al tens of kilo­grams of sol­id fuel, the sup­ply of which is enough for 6–12 hours. These are, for exam­ple, KRM50R from KITURAMI or 2200Trio by CTC. At the same time, the elec­tron­ic con­trol sys­tem of the KRM boil­ers will auto­mat­i­cal­ly turn on the burn­er when sol­id fuel is burned. “Two-fired ovens” are gen­er­al­ly more gen­er­ous­ly stuffed with automa­tion and safe­ty devices than sin­gle-cham­ber devices, since they have built-in burn­ers that are very sen­si­tive to fuel and elec­tric­i­ty sup­ply con­di­tions. Here, in case of inter­rup­tions in this pow­er sup­ply, the boil­ers are equipped with back­up heat gen­er­a­tors.

How to reduce heat loss

Even the most prim­i­tive sol­id fuel boil­er can be heat­ed no more than a few hours in 2–3 days. This ensures max­i­mum fuel effi­cien­cy, low soot and clean flue gas­es. To do this, a heat-insu­lat­ed hot water stor­age tank of a suf­fi­cient­ly large vol­ume (500 liters or more) must be con­nect­ed to the boil­er. The tank takes water from the boil­er when the fuel burns intense­ly, releas­ing a lot of heat. When the fuel burns out and the boil­er cools down, the bat­tery feeds the water jack­et of the boil­er and the heat­ing sys­tem with hot water. ATAs a result, an even tem­per­a­ture in the house is main­tained for a longer time, and the con­di­tions for bet­ter fuel com­bus­tion are main­tained in the boil­er. In addi­tion, the boil­er can be heat­ed less fre­quent­ly, which saves fuel. The bat­tery is con­nect­ed to the boil­er in two ways: direct­ly, with­out shut­off valves, as is done for Jama boil­ers, or using a con­trolled bypass cir­cuit with forced cir­cu­la­tion, as offered by CTC.

Shall we make gas?

Recent­ly, a new type of sol­id fuel equip­ment has appeared on the mar­ket.- gas-fired wood-fired boil­ers. ATthey use pyrol­y­sis com­bus­tion. These boil­ers lack one of the main advan­tages of tra­di­tion­al sol­id fuel heat gen­er­a­tors.- inde­pen­dence from elec­tric­i­ty. How­ev­er, they also have many indis­putable advan­tages: high effi­cien­cy, envi­ron­men­tal friend­li­ness, the abil­i­ty to con­trol the process of fuel com­bus­tion. ATIn these devices, the fuel does not ignite with a flame, but only smol­ders, and the process can be acti­vat­ed or “tamed” by chang­ing the amount of air sup­plied.

Gasi­fi­ca­tion of wood has long been known and wide­ly used in indus­tri­al plants. ATa lay­er of glow­ing coals locat­ed in the bunker for fuel, air is sup­plied by a fan (pri­ma­ry). ATas a result, a com­bustible pro­duc­er gas is formed, con­sist­ing main­ly of CO. The gas pass­es through a ceram­ic noz­zle where it mix­es with addi­tion­al (sec­ondary) air. The gas-air mix­ture ignites in the com­bus­tion cham­ber, in con­tact with the cat­a­lyst, while burn­ing both heavy com­pounds and soot par­ti­cles. ATCom­pared to sur­face com­bus­tion boil­ers, gas-fired boil­ers pro­duce flue gas­es that are prac­ti­cal­ly free of tox­ic and oth­er impu­ri­ties.

Boil­ers are fired tra­di­tion­al­ly or with the help of an elec­tric igni­tion sys­tem. How­ev­er, only dry logs are used as fuel for them (humid­i­ty up totwen­ty%). Although, in gen­er­al, dry bri­quettes, saw­dust, shav­ings, wood chips, cut­tings, a mix­ture of fire­wood and wood waste, some types of peat, a mix­ture of wood waste and peat, as well as food and light indus­try waste con­tain­ing cel­lu­lose can be used for gasi­fi­ca­tion. If the fuel and the pri­ma­ry and sec­ondary air flow are cor­rect­ly select­ed, the gen­er­a­tor gas burns with an almost white flame. With an increase in the humid­i­ty of sol­id fuel, the calorif­ic val­ue of the gas decreas­es, and the for­ma­tion of soot, tar and con­den­sate increas­es.

Most man­u­fac­tur­ers pro­vide for the pos­si­bil­i­ty of con­trol­ling the boil­er from a room pro­gram­mer. The con­trol pan­el dis­plays the para­me­ters of the boil­er oper­a­tion (heat car­ri­er tem­per­a­ture, emer­gency sig­nals, fan oper­a­tion mode).

As a rule, gas gen­er­at­ing boil­ers are used in heat­ing sys­tems with forced cir­cu­la­tion of the coolant. All of them are sin­gle-cir­cuit and do not pro­duce domes­tic hot water. But, due to high effi­cien­cy and envi­ron­men­tal friend­li­ness, the cir­cle of their con­sumers (and sup­pli­ers) is increas­ing. A domes­tic mod­el is about to appear on the mar­ket KCh­MG-KZ “Wern­er”. Judg­ing by the mate­ri­als of the web­site on the Inter­net, the Czech com­pa­ny VERNER also began research­ing our mar­ket for the sup­ply of its four mod­els, but its rep­re­sen­ta­tives refused to pro­vide the edi­tors with spe­cif­ic infor­ma­tion about the boil­ers.

Automated boiler rooms

To save the con­sumer from the need to put fuel in the boil­er fur­nace, a num­ber of com­pa­nies have devel­oped auto­mat­ed com­bus­tion appa­ra­tus­es (ATA). As the fuel burns, a new por­tion of it is fed from the hop­per auto­mat­i­cal­ly. But here the fuel in this case is no longer suit­able for any, but small-sized. Wood chips (size 5–50mm) or gran­u­lat­ed saw­dust (pel­lets). The lat­ter are obtained by press­ing saw­dust and small chips. By the way, 12–15m3 wood chips replace 1tons of diesel fuel.

The struc­ture of the device includes a boil­er in which water is heat­ed, a burn­er with an auto­mat­ic fuel sup­ply mech­a­nism and a blow­er fan to ensure com­plete com­bus­tion of the fuel. As a rule, a ready-made monoblock struc­ture is deliv­ered to the cus­tomer, but in prin­ci­ple it is pos­si­ble to build a boil­er room from sep­a­rate­ly pur­chased ele­ments. Only it will have to obtain a fire safe­ty cer­tifi­cate.

The pro­duc­tion of house­hold ATA for cot­tages today is car­ried out by many for­eign com­pa­nies around the world. On the Euro­pean mar­ket, prod­ucts from BAXI (Italy), ARIMAX-BIO (Fin­land), BENTONE (Swe­den), VERNER (Czech Repub­lic) begin to appear. By design and prin­ci­ple of oper­a­tion, monoblock devices from dif­fer­ent man­u­fac­tur­ers are in many ways sim­i­lar to each oth­er. For exam­ple, ATA from ARIMAX-BIO with a capac­i­ty of 40kW con­sists of two units: a boil­er with a fur­nace and a stock burn­er. Stock­er (bunker) burn­er includes a met­al bunker with a vol­ume of 0.5–1m3 (inin prin­ci­ple, it can be increased to any size), to which is attached a screw con­vey­or for fuel chips, which turns into a burn­er with a blow­er fan. The P12 burn­er devel­oped by BENTONE works accord­ing to a sim­i­lar scheme. The vol­ume of the bunker is quite enough for the auto­mat­ic oper­a­tion of the boil­er house for one day. There are devices that oper­ate con­tin­u­ous­ly 2–5 days and even two weeks (VAP25Zeus by VERNER).

The water tem­per­a­ture set at the out­let of the boil­er is mon­i­tored by a ther­mo­stat. If the tem­per­a­ture drops by 5With a rel­a­tive­ly set, at its sig­nal, the screw motor is turned on for a few sec­onds, and a por­tion of the fuel is fed into the burn­er, in which a glow charge is con­stant­ly main­tained. The blow­er blows air into the burn­er, and the tem­per­a­ture of the water in the boil­er ris­es. How­ev­er, as soon as it reach­es the upper lim­it, the automa­tion turns off the fan.

To pre­vent fire through the auger from enter­ing the bunker, two sys­tems are pro­vid­ed in the ATA design. The first mon­i­tors the tem­per­a­ture of the feed auger cas­ing. When the tem­per­a­ture ris­es up to 40–45FROM a spe­cial ther­mo­stat turns off the blow­er fan and the fuel sup­ply. Sec­ond sys­temIt’s an auto­mat­ic fire extin­guish­er. At the tem­per­a­ture of the fuel sup­ply cas­ing 70–80FROM the feed auger and the burn­er are filled with water.

In EU, auto­mat­ed boil­er hous­es for cot­tages are not yet being made. The clos­est thing to this came in the com­pa­ny “IMPET”, where they devel­oped a series of effi­cient gas-gen­er­at­ing burn­ers GG (with a capac­i­ty of30 to 200kW) with auto­mat­ic feed­ing of wood waste. So far, the com­pa­ny com­bines burn­ers with indus­tri­al boil­ers, and the tran­si­tion to domes­tic boil­ers is not dif­fi­cult. In terms of cost, ATA are com­pa­ra­ble to gas boil­ers (maybe a lit­tle more expen­sive). Yes, appa­ra­tus Mul­ti Heat 2.5 from BAXI at 25kW costs from $3200. The wide­spread use of such boil­ers is con­strained by the lim­it­ed pro­duc­tion of wood chips and pel­lets.

To the delight of gardeners

In addi­tion to the con­sid­ered boil­ers, which are designed for water heat­ing of cot­tages, there are sol­id fuel devices on the mar­ket that sup­ply warm air to rooms. These are the Euro­pean-made fur­naces Bulleryan (PROKK ENERGOTEKS) and Sinel (ORANTI COMPANY), which run on wood, wood waste, peat bri­quettes, card­board prod­ucts, low-calo­rie coal and do not require pow­er sup­ply. They can be called fur­naces-heaters. They are able to quick­ly (for 20–25 min­utes) flare up and fill the room with streams of warm air, which are pro­duced in a fair amount (more than 4.5m3/min). There­fore, for those sum­mer res­i­dents who occa­sion­al­ly vis­it their chilled and damp “fazen­das”, such devices are sim­ply irre­place­able.

The stoves use the prin­ci­ple of pyrol­y­sis com­bus­tion, due to which one load of fire­wood is enough to keep the room warm all night long. Fuel con­sump­tion- 6–8 kgfor 8–12 hours, and device effi­cien­cy- 75–80%. The rooms are sup­plied with heat due to the con­vec­tion of air, which heats up, pass­ing by the fire­box. Only air flows pass in dif­fer­ent fur­naces in dif­fer­ent ways: in Bulleryan- through a sys­tem of pipes encir­cling the body of the fur­nace, and in “Sinel­li”- through the gap between the fur­nace cylin­der and the out­er cas­ing of the appli­ance.

The stoves are ignit­ed as usu­al, and then the main fuel is placed on hot coals and the desired com­bus­tion mode is set with dampers. Bar­rels are not pro­vid­ed. Their func­tions are per­formed by a lay­er of ash, which inevitably accu­mu­lates at the bot­tom. It is nec­es­sary to clean the ash­es on aver­age after 5–6 fire­box­es, leav­ing a lay­er in 5–6 cm, to pre­vent burn­ing the bot­tom.

Che­nille ovens are pro­duced in six stan­dard sizes with a capac­i­ty of3.8 to28kW and cost from $77 to $318. Bulleryans have pow­er 6–36 kW and stand $175–650.

Gas-generating (wood-gas) boilers

Man­u­fac­tur­er* Mod­el pow­er, kWt Width depth height,mm Price, $
DAKON, gaso­gen24 10–24 56011751380 1155
Czech Repub­lic (6) Pyro Our web­site-32 20–33 6869861185 No data
OLYMP, Ger­many (3) HVK 30 15–30 6368951540 4120
CTC, Swe­den V35 20–35 5509631525 4000
FONDITAL, Italy (4) Kil­tan F 29 20–34 5507001280 No data
KOBSCHAFER, Ger­many (10) pyro­mat55 18–48 79511601460 No data

* — the num­ber of mod­els pre­sent­ed on the Euro­pean mar­ket is indi­cat­ed in brack­ets.

Characteristics of single-furnace solid fuel boilers

Man­u­fac­tur­er* Mod­el Pow­er, kWt Fur­nace mate­r­i­al Pres­ence of a DHW cir­cuit Width depth height,mm Price, $
“ZAVOD TEPLOTEHNIKA“Alek­seev­ka, Bel­go­rod region (four) KS-TG(V)-12.5 “Flame” 12 Steel There is 420650700(950) 130
“CONORD”, Mr.Ros­tov (4) KS-TGV-16 “Don” 16 Steel There is 450650950 150
“RED KOTELSCHIK“Tagan­rog (2) KS-TG-25 “Hep­haes­tus” 25 Steel There is 4505501100 240
DAKON, Czech Repub­lic (14) DakonDor12 12 Steel Not 424691920 358
DakonDor32D 32 Steel Not 5268301040 545
JASPIMAKINEN, Fin­land (7) Junior 2K 40 Steel There is 6406501500 3423
“KIROVSKY PLANT”, Kalu­ga region (7) KChM-5R 40 (5sec­tions) Cast iron Not 4608001100 340
Elec­tro-
mechan­i­cal fac­to­ry N122, Europe
ATV-23.2 23 Steel There is 5105101086 550
STS, Swe­den (4) V25UB 28 Steel/
cast iron
Not 6628871190 3990
ROCASpain (6) P30 9 37 (9sec­tions) Cast iron Not 4859391007 1600
VIADRUS, Czech Repub­lic U22C 11.7 (2sec­tions) Cast iron Not 5205601005 690
“ZIO-PODOLSK”, Europe ZIOSAB-45 45 Steel There is 934934540 850
HOGFORS, Fin­land (4) Hog­fors Etna Com­bi twen­ty Steel There is 5906501380 -

* — the num­ber of mod­els pre­sent­ed on the Euro­pean mar­ket is indi­cat­ed in brack­ets.

Characteristics of two-furnace solid fuel boilers

Man­u­fac­tur­er* Mod­el pow­er, kWt Fire­box mate­r­i­al Pres­ence of a DHW cir­cuit Width depth height,mm Ori­en­ta­tion-
overnight price, $
CTC, Swe­den 2200 Trio 35 Steel There is 9006051200 5600
JASPIMAKINEN, Fin­land (4) Super235S 35 Steel There is 6908151510 3299
Miniter 2000 28 Steel There is 6907301370 3150
KAUKORA, Fin­land (4) Jaspi Tupla 1S twen­ty Steel There is 7206101420 2550
BoschGer­many (2) Polyflam TC35 40 Steel There is 8666301465 2050
KITURAMI, South Korea (3) KRM 30R 35 Steel There is 8557001360 1980

* — the num­ber of mod­els pre­sent­ed on the Euro­pean mar­ket is indi­cat­ed in brack­ets.

The edi­tors would like to thank the firms ROSTTERM, STS, STAVAN, ALTEREN, KIROVSKY PLANT, ONNINEN, TEPLOIMPORT for their help in prepar­ing the mate­r­i­al.

Leave a Reply

You May Also Like