- Home Improvement
Flickering flames, heating the old fashioned way.
As far back as prehistoric man, fire has been a fascinating necessity. Fire and its receptacles have played a vital role in our lives, whether it be to light a darkened cave, warm a king's castle, prepare a pioneer's meal or provide a romantic setting for lovers. Today a fireplace or wood stove can also be an economically sound and, to some degree green, investment.
Improving an existing fireplace
Improvements can be made enabling you to rely on the fireplace as part of your home heating source. The addition of a three-shaped flat-tube grate is the first step. Three levels or four flat tubes with a one inch hollow allowance for air passage results in heat-absorbing surfaces at right angles to rising heat from the fire. The heat radiated through the passages travels quickly to the cooler upper tubes producing a higher temperature. To improve the efficiency of this system additional one inch wire lath strips - one atop the other - can be inserted into the tubes. Heat is distributed through conduction but still allows for the passage of air. This idea is perfect for older fireplaces.
Since humid air possesses better heat exchange qualities than dry air, the use of a humidifier is advisable. Installed next to the fan in the air path, a metal box partially filled with water causes air which is blown over the hot water to pick up moisture before being delivered to the grate. The acceptable standard for air humidity is around 35 percent, although this varies from one individual to another.
You have now achieved a 20 - 25 percent increase in efficiency but a substantial amount of heat is being lost up the flue. To remedy this problem, a lath-filled hollow steel jacket can be fitted against the firebox's sides and back. Heat is conducted to the interior of the jacket again using one inch strips of wire lath. This will increase efficiency by another 11 - 15 percent.
Finally, in order to take advantage of the unignited gases wood produces - which are a valuable heat source - glass doors with a small adjustable damper in the bottom rail are installed. This regulates the amount of air admitted to the firebox resulting in more effective heat production. Glass doors increase efficiency be three to five percent for an overall 34 to 45 percent increase in the efficiency of your fireplace.
Taking the wood stove one step further is the installation of a catalytic combustor. One of the first models was released in the 80s and was not well received - partially due to cost of more than $400. Prices have come down immensely - most under $200 - and tests have proven the benefits involved. Catalytic combustors are more than 90 percent combustion efficient with 70 - 90 percent less creosote build-up.
Strict regulations on the emissions for pollutants of wood stoves is enforced by Environmental Protect Agencies. Installing a catalytic combustor in the wood stove forces all smoke to be re-burnt before entering the chimney resulting in cleaner emissions being released into the air.
The catalyst is a mixture of noble metals - usually palladium and platinum - which lowers the ignition temperature of the gases and combustibles found in smoke. When the smoke and gas react with the catalyst they ignite, but the catalyst is unchanged which results in long life. Effluent is reduced drastically and a minimal amount of residue occurs. Coals and ash are reduced to a fine white powder and the combustion utilizes wood as a fuel source with no waste.
The most important advantage, though, lies in the fact that catalytics have been found to be 90 percent efficient with outputs as low as 6000 - 8000 BTU (British Thermal Units) per hour as compared to 80,000 - 100,000 BTU per hour from a gas forced air furnace. With a lower burn rate, higher heat transfer is possible and less fuel is required. More heat stays in your home than goes up the chimney.