I prepared material for a conference yesterday. Here is a piece of that material that may be helpful to better understand some basics.
Basics of installation for a wood gasification boiler.
1. All plumbing after the boiler to the heating system/emitters is essentially the same as with any other type of hot water boiler, whether wood, electric, propane, natural gas.
2. Unique aspects of the installation.
a. Boiler return water protection: usually required – thermostatic valve, mechanical or motor driven, or loading unit – mixes boiler output with return water from the system to return water to the boiler at a temperature generally above 140F. This is important to prevent condensation of water vapor in the boiler and corrosion.
b. Flue: generally Class A chimney (high temperature, stainless steel, double wall, insulated, rated at 2100F).
c. Hot water storage, optional to required: allows for increased efficiency in operation and longer times between boiler firing.
3. Important considerations.
a. For proper boiler sizing and heating system design: calculation of heat loss for all heated structures.
b. For heating system design: determination of required hot water flow rates, selection of proper pipe sizes to carry the water flow, determination of flow resistance in piping and heat emitters (pump head) at required flow rate(s), selection of circulating pump(s) to meet performance requirements.
c. For greater flexibility in use and operation: low temperature heat emitters which provide needed heat at water temperatures of 140F or less, such as radiant in floor, radiant panels, high performance baseboards, etc.
d. For greater efficiency and reduction in cost: locating the boiler (and storage, if any) in a space that otherwise would be heated: captures boiler operation heat loss for usable heating.
4. Wood supply.
a. Must be “well seasoned,” that is, dried to a moisture content usually in the 15-20% range, although some boiler manufacturers permit higher moisture content. Must not be “green” wood. Wood cut, split and stacked in the open air, with good air circulation, will take about one to three full summers to dry to a moisture content of 15-20%, depending on the wood species.
b. Generally should be cut to lengths between 18 inches and 2 feet, depending on the boiler, for ease of handling and loading. Should be split to diameters recommended by the manufacturer, generally 3 to 6 inch diameters.
c. Should plan to have sufficient well seasoned wood on hand at the beginning of the heating season to meet expected need for wood fuel.
d. Wood suppliers providing “seasoned” wood usually supply wood not dried sufficiently for satisfactory burning.
Basics of installation for a wood gasification boiler.
1. All plumbing after the boiler to the heating system/emitters is essentially the same as with any other type of hot water boiler, whether wood, electric, propane, natural gas.
2. Unique aspects of the installation.
a. Boiler return water protection: usually required – thermostatic valve, mechanical or motor driven, or loading unit – mixes boiler output with return water from the system to return water to the boiler at a temperature generally above 140F. This is important to prevent condensation of water vapor in the boiler and corrosion.
b. Flue: generally Class A chimney (high temperature, stainless steel, double wall, insulated, rated at 2100F).
c. Hot water storage, optional to required: allows for increased efficiency in operation and longer times between boiler firing.
3. Important considerations.
a. For proper boiler sizing and heating system design: calculation of heat loss for all heated structures.
b. For heating system design: determination of required hot water flow rates, selection of proper pipe sizes to carry the water flow, determination of flow resistance in piping and heat emitters (pump head) at required flow rate(s), selection of circulating pump(s) to meet performance requirements.
c. For greater flexibility in use and operation: low temperature heat emitters which provide needed heat at water temperatures of 140F or less, such as radiant in floor, radiant panels, high performance baseboards, etc.
d. For greater efficiency and reduction in cost: locating the boiler (and storage, if any) in a space that otherwise would be heated: captures boiler operation heat loss for usable heating.
4. Wood supply.
a. Must be “well seasoned,” that is, dried to a moisture content usually in the 15-20% range, although some boiler manufacturers permit higher moisture content. Must not be “green” wood. Wood cut, split and stacked in the open air, with good air circulation, will take about one to three full summers to dry to a moisture content of 15-20%, depending on the wood species.
b. Generally should be cut to lengths between 18 inches and 2 feet, depending on the boiler, for ease of handling and loading. Should be split to diameters recommended by the manufacturer, generally 3 to 6 inch diameters.
c. Should plan to have sufficient well seasoned wood on hand at the beginning of the heating season to meet expected need for wood fuel.
d. Wood suppliers providing “seasoned” wood usually supply wood not dried sufficiently for satisfactory burning.