02 May, 2011

Stainless steel biomass heater produced in-house - by Jose

Update: If you wanna make this project on your own, I advise you to not put the horizontal steel sheets to avoid problems with smoke; those sheets cool down the fumes a lot and it is bad for verting, the tar and slag will stick to the tube. To avoid this situation the temperatures of the smokes must be over 300ºC.
If the tube is long, we have to put an insulated tube to maintain the ignition temperature inside of it.

This entry I will devote to the project of Jose, who kindly sent me photos and details of his proposed home in stainless steel boiler., As I am concerned by the crisis and the environment. Hope you enjoy it as much as me.
Project Details

Photo of the stove in operation in the absence of cover with drywall

(This document was translated using Google Translator from the original spanish article

Jose, another hands of Toledo has developed a wood boiler full of stainless steel., And assures us that is like a shot, in 10 minutes take the set temperature 60 degrees and starts pumping, the house is large (210m) and 2h hot. Is supercontento, of which I am very happy because it saves money and uses renewable energy such as wood (= 0 Co2) and get some exercise step carrying firewood (with saving him from the gym ;-).
Started commenting on this post , in which he commented that before light was paying € 500 every two months using a heat pump, while the neighbors, heat radiators "blue" spent € 600! per month, an entire salary.

Advantages of biomass
There will be people who think "gas is the most comfortable, give it to the thermostat and forget." And it is true, only that the discomfort comes from the ax € 150 per month, money that goes out of Spain, in addition to increasing climate change.
Wood waste helps the local economy, providing jobs in the collection, cleaning and transporting forest biomass.
Besides these stoves, wood metiéndoles good, they just need loads every 3 or 4 hours, about 15 kg. can heat up a house of 100 square meters, and is a good exercise to eliminate the daily stress, thereby relaxing the contemplation of the fire!

Jose has sent us some pictures of your home furnace, which is quite an achievement. Finally, Jose has decided to create their own blog to answer people's doubts (click to enter) , and collaborate on anything with those interested in making a similar.

In price, including labor and materials can go over 2000 €, an amount that will certainly save in two or three years using wood as fuel instead of gas.
The radiators of thermal emitters has taken advantage of them pulled the oil and endurance. As radiators are others which to adapt a pair of plugs, keys and holders can benefit them.
Although not involved in welding, knows the subject and the camera has been prepared for water leaving the sides.

Make one of these is not as complicated as it sounds, it should only hold 1.5 bar, so that plate cameras may be 2-3 mm in stainless steel if it is better to put more normal width.

The upper chamber initially had no water, only the sides and bottom, as he thought, there is generated a very high temperature and water tends to stagnate at that site, with a sudden rise in temperature and accumulation air.

As shown in the picture below, it has moved only 3 plates welded to one side and supported on supports on the other side (just be welded to the side to let them dilate) and with a gap of 5 cm. the other side, through which the smoke.

He even has put the door window with ceramic glass resistant to high temperatures, wow!

Operating Details annotated by Jose
"First, the three sheets that look at the superiors are opposed to moving gas in an" s "and not go directly, we should provide a saving in fuel consumption.

The 2000 budget included € takes copper pipe, elbows, keys, holders, tin, torch, (van several meters because the house is big enough) and all safety and operating instruments: prescómano, pump, damper, thermal relief valve, (not yet installed, which will teach us next photos), FP (provisional galvanized issue price), etc ...
In reality, the steel for the boiler will cost € 550 but if it is carbon steel will cost much less. If you buy in a store of iron would pretty cheap.
If not loaded properly at first, the lower the deposit is usually a bit cold because the flames are above this part of depósito.Esto think 100mm would be solved by removing the tank on the floor, thus saving material.
On the other hand is a guarantee it has the coldest area, because if you spend adding fuel, this dampens the risk of overheating. That works very well, it is striving for perfection even though we know that is impossible.
The hot smoke must leave because the flue pipe is peeling, so I do not think there are problems with soot, we will see over time ...
A detail: The gas retaining plates, should only be welded heavy plate on each side and support them on plates at the other end without welding, but it is possible that when dilated by the heat, they can warp and shut off the gas to the fireplace.
The boiler weighs approximately 150kg or more. Then dode support will rise which is heavy plate angle and weigh about 50kg more. "
He sent us a plan with measures, which detail:

The measures are:
Height: 850mm
Width: 600mm (50mm plus deposit)
Background: 600mm (25mm plus deposit
The thickness of the sheet where the fire is going steel. of 6 mm., while everything else can be 3 mm. To be cooled by water, the plates can be fine and the boiler be lighter.
He says that the actual height is 750mm which is what measures the water tank, but the plate is 6mm fireplace is 100mm high and to leave a gap under the screen where it will burn the wood where enter the air from the street and houses the box of ashes.
He says that if he would do it again less background, such as 500mm, and the water tank would also removing height 500mm, cutting it down, because even performs very well for heat exchange so I would save a little more consumption of fuel to have less water to heat.

Stove still without a camera on top

Points for improvement
After analyzing the design, and as I have said it, you can improve in the following details, other readers may be considered as constructive criticism.
With this I am not saying that their design is bad, it works very well, but can be improved, and these ideas come in handy if you want to save time and money:
  • On the plates that deflect the smoke does not capture heat diverting S-shaped smoke only makes them get hot, but the heat from the smoke will be the same if instead of S (which stops shooting, yes) is time that goes by the side. For example, if you place a single sheet closing off the exit of smoke and leaving 3 or 4 cms. on each side, with a vertical plate of 10 cms for the smoke to pass on that section attached to the cameras, would have more performance, there would be no buildup of soot and would be easy to clean. In fact, this is how they are made ​​of oil-fired boilers. At the end of the day where you recover 80% of heat is when the smoke "rub" the camera, only the lateral contact area (you can check the water temperature reached at that point, much higher than has, for example in the center of the camera).
  • You could also remove the bottom half of the side chambers, as he commented can be placed in the top half, where the heat falls more, not less water to heat, but it is not necessary. If you want to give more capacity to absorb water better overheating, you can also give more width to the cameras ..
  • If I had time, would also in the top chamber, communicating with other deposits. In this way even prevent the top burning due to high temperatures, and better take advantage of the fireplace.
  • Finally put a vent tube with a camera to prevent tar build up inside for cooling the flue gas.
Jose finally added another camera angle on the top, coupled with around the boiler, to capture the heat from the top, and now consume less wood and smoke still more cold out, so sometimes spout smoke some resin drips.
To avoid leaking must be taken to insulate the pipe to cool as much as possible, with stainless steel insulated chimney. and all joints inward (to drip into the boiler leak if anything), because the fumes are condensed when cooled too much (water, tar, etc).
In addition he has another fireplace for the local extraction of fumes, and will prepare to activate automatically when you open the door and remove the little smoke can escape.

Caldera failing to place the plasterboard

As you can see the last photo, also has added a couple of security features, as we said:
There are a number of security elements that must function in the absence of a eléctrico.Aparte supply UPS is not indispensable safety valve and pressure switch in biomass boilers is due to thermal relief valve. This valve is usually calibrated at 90 ° to open and expel the hot outside. Of course it works without power and has a probe that should be put on the hottest area of the boiler. See the link (click) .

Maximum working pressure: 10 bar.
Temperature range: 5 ÷ 110 ° C.
Hair length: 1300 mm.
This valve should counter with an automatic fill valve. This takes care to always keep the same pressure in the circuit. At the same time makes the valve to the hot water does not return to the network. In the event that the water reaches 90 º thermal relief valve discharge water before it reaches a boil and immediately fill auto fill valve circuit cold water reducing peligro.Funciona course completely without power.
This fill valve must always receive mains water pressure naturally without pressure pump, and that by failing light, we have them. It is advisable to put a cock before and if you go home for a long time, keep cerrada.Puedes back from vacation and the house and the swimming pool through a leak. Here you can see :

Range: 0.3 ÷ 4 bar.
Maximum inlet pressure: 16 bar.
Maximum temperature: 70 ° C

I mentioned in previous emails with another smaller expansion tank would have sufficed, and it is true, but an oversized tank only gives us benefits, but obviously more expensive, wood, bigger is better.
It is also important regulator acts tiro.Éste closing and opening the shot through a chain and a shaft which is driven by a probe that is included in the controller. If you look at the last photo you sent, you will see a string on the right. Because that is the regulator. Probe is inserted in the water tank. Bring thread 3 / 4 and has a selectable temperature wheel. If adjusts to 60 for example, when the water reaches 60 º valve acting on the shaft and the chain, closing the door moving shot, when the temperature drops about 7 º abrir.Esto again protects us from overheating and can load While wood home, because when there is excess heat, the gate is closed and choke the fire.
Can be found here .

Damper, double safety.
Male threaded connection.
Range: 30 ÷ 100 ° C.

Moreover, with underfloor heating must be taken at all times a temperature control, because as you know, has to be significantly lower than with radiators. With the wood is very hard to control temperature grade to grade because you can not put out the fire immediately and on again, which with gas or diesel is fine.
Anyway, you could do with mixing valves, sinks and a buffer tank, but of course that costs so much money.

However, in the case of floor heating, there must be no problem as long as temperature let off the fire when the house has reached the proper temperature, soil acts as a buffer tank as much material is then heated releasing heat.

Thanks Jose for your input, I hope we keep up with your progress! We must raise awareness of the benefits and cleaned boilers. Zero smoke, all virtues.

I liked both your furnace until I'm considering changing mine to a wood stove tempered steel!
Responsibility of the author:
This tutorial, like everyone else, are made ​​publicly available for one that may come in handy, I am not responsible for what happens on the bad or good use of these instructions, each must use their common sense and knowledge to safeguard their property and physical.

No comments :

Post a Comment