Osburn OB01801 - Manual (Page 25)

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3.5 Maintaining The Fire
Your Osburn insert will work best if a thick bed of hot embers is maintained in the bottom of the
firebox, and a minimum of two large pieces of seasoned fuel are added. Combustion efficiency is
largely related to establishing a hot ember bed, and hot firebox temperatures. The quicker the
insert and fuel get up to operating temperature, the better. A small intense fire is preferred to a
large smouldering fire, both to improve combustion efficiency and to reduce the amount of
creosote emitted. The best performance will be achieved by adding relatively small amounts of
fuel to a well established ember bed, and then operating with the air inlet control open long enough
to achieve a hot fire. Cordwood should be placed with air in between individual pieces. Use a
poker to make an air channel in the embers below the wood, this will allow air to flow under the
wood for a more efficient burn.
Extended burn times can be accomplished by first operating the insert on a full load with the air
inlet controls wide open. Once the fire is well established, and the moisture has been driven out of
the wood, reduce the air control to a lower setting. The unit should then burn cleanly without
smoldering. If the fire smolders without flame, re-establish a hotter fire before moving the air
control to the lower setting. A yellow flame burning in the top of the firebox is a good indication
of a clean efficiently burning fire.
Refuelling technique is important for good performance. The best efficiency and performance
from your insert can be achieved by adding partial loads of fuel and allowing them to get up to
operating temperature before adding additional fuel. Adding a large amount of fuel at one time
will increase the time required to get the fuel up to its ignition temperature, and an extended time
to reach optimal performance. When refuelling, open the air control or hold the door partially
open 1” (25 mm) or less, long enough (less than 5 minutes) so that the fire has well established
flames. When refuelling, care is required to ensure that fuel or embers do not fall out of the door
opening. The unit will burn at about 2.0 to 2.5 lb/hr (.9 to 1.1kg/hr) at its minimum setting;
approximately 20 to 25 lbs (9 to 11.3kg) of wood are required for an extended burn.
In order to achieve an optimum efficiency from your unit, we suggest that you operate it with the
air control completely closed. Make sure that you have a good fire going and an adequate ember
bed before you completely close the air control. Closing the air control too soon will lower
combustion efficiency and may cause the fire to die out. The addition of a blower (if not already
included) is highly recommended to maximize your unit’s efficiency.