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Always used seasoned wood
. This is obvious, but a lot of customers who think they have seasoned wood often do not. The new EPA emissions standards that went into effect last year require burning wood that has no more than 20% moisture content. If you are not sure about your wood, we have an inexpensive moisture meter in our on-line store. (A proper reading is taken after splitting a piece of wood and measuring as close to the middle as possible.)

Let the wood burn down to coals before reloading.
Anytime there is a log in the firebox, there's moisture that needs to be eliminated. This can only be done by letting the log burn down to coals.

For Classic models, rake the coals forward each day to allow the fire to burn from the front to the back. For E-Classic and Classic Edge models, use the push rod to loosen the entire firebox floor and distribute the coals over the air charge tube.

Never let the ash build up high enough in an E-Classic or Classic Edge to cover any of the firebox air vents.

Check the door seal each day to make sure the seal is tight and not leaking any air or smoke.

For furnaces with door dampers, make sure the damper door is not sticking and the solenoid moves freely.

Ashtrol is a pH neutralizer for the firebox that helps reduce the acidity found in wood. Distribute a scoop each day in a different area of the firebox.

The air pulse for E-Classic and Classic Edge models should be adjusted occasionally through the heating season to keep the coals hot when the furnace is idle.

Clean the ashes in the firebox (Classic models) or Reaction Chamber (E-Classic and Classic Edge models) once a month along with the chimney tee. Keeping the ash level down and chimney tee clear will maintain the proper draft necessary for proper combustion. On E-Classic and Classic Edge models, clean the heat exchangers once a month to keep them clear of any buildup.

Water testing twice a year is important to make sure you have the correct amount Corrosion Inhibitor Plus in your water. Some customers put in a little each year without testing and discover that making water too alkaline can be just as bad as making it too acidic. Test your water with a standard water test kit or an antifreeze-based water test kit. If your potassium permanganate is more than two years old, get a new one here. To make water testing easier, instead of taking a water sample from the site gauge, use the hose bib on the thermostatic valve. Remove about a quart before taking your sample and pour the quart back into the top of your furnace to save the water and chemical.

If you are just topping off your furnace water, filling the water jacket through the air vent on the top of the furnace is fine. However, if you are filling an empty furnace (and do not forget to add the proper amount of corrosion inhibitor before filling with water), be sure to follow the procedure in the manual. The procedure uses the drain valves and ball valves on the thermostatic valve that is located inside the building to fill the furnace with water. This is the only way to purge all of the air from the lines going to and from the building. Just filling the furnace from the air vent and then turning on the pump will cause an airlock and possibly burn out the pump.

If you have a second or third set of lines exiting the furnace and heating additional buildings, once the furnace is full from using the thermostatic valve on the first line, repeat the procedure at the second and third thermostatic valves to purge the air from those lines.

Whenever you add water or fill an empty furnace, do not forget to take a water test the following day. Topping off water on a regular basis will dilute the corrosion inhibitor enough to turn the water acidic. The correct amount of corrosion inhibitor is essential for proper functioning and is necessary to ensure warranty coverage. If the water test shows the corrosion inhibitor is low, add a quart through the air vent, wait a day and take another water test. Repeat this procedure until the water tests correctly for proper corrosion inhibitor concentration. If the water test shows the corrosion inhibitor is high, then drain some of the furnace water and top off with fresh water through the air vent. Again, wait a day and take another water test.

The pH of water that will be used in the furnace should be around 6.0 to 7.5. If it is not, then another source of water will need to be used. Also, you want to use softened water if possible, but not distilled water. Once the furnace is filled and the correct amount of corrosion inhibitor is used, the pH should test between 8.0 and 9.5. Be sure to check both the nitrite level (the sulfuric acid and potassium permanganate test) and pH level (the pH strip test) when performing a water test.

Finally, if you have antifreeze in your outdoor wood furnace, we have a special glycol-based water test kit that must be used in place of the standard water test kit that comes with the furnace. Also be aware that not all antifreeze solutions are compatible with the glycol-based water test kit. Contact us for more information.