If all ash has been removed from the firebox, then it can upset the supply of air to the base of the fire. It can aid the fire by retaining some ash when cleaning out the firebox.

Fuel Quality – If not using properly seasoned wood, it can be difficult to start the fire as energy is consumed to remove moisture from the wood rather than propelling the combustion process.

If your door glass has cracked without being caused by an impact, it could be that the glass retainers have been overtightened. Overtightening the glass retainers will not allow for movement as the door expands and contracts with heat, this will result in your glass cracking. 

i) Burning unseasoned wood — if the wood is too wet, it will cause the glass to blacken. 
ii) Appliance operated at low temperature — after an overnight burn where the air slide control has been fully closed, the glass may have blackened. When the fire is re-stoked and burning on the high heat setting, the blackened glass should self-clean. 
iii) Problems with the flue — insufficient flue draught can cause the glass to blacken. If the flue is too short, not properly insulated, or in a position that results in a downdraught, then there will be insufficient flue draught. Contact the installer should this happen.

Smoke spillage can be caused by many factors – the most common of which are extraction fans/rangehoods, or an issue with the flue system. Extraction fans/rangehoods should not be installed in the same room as the heater as they can create negative air pressure in a room, which can cause smoke spillage from the heater. It is also not uncommon to experience a downdraught in your flue system, this can cause smoke spillage from your heater. To reduce the chance of a downdraught, the flue must be installed in line with AS/NZS 2918 to ensure that it is tall enough to not be impacted by its surroundings and provide adequate flue draught. In some cases, this is still not enough to prevent a downdraught – in these circumstances an additional length of flue and/or an anti-downdraught cowl can resolve the issue. In addition, the flue must be clear and unobstructed to ensure adequate flue draught – refer to the operating manual of your unit for instructions on inspecting your flue. 

If you find that your heater is burning too quickly even with your air controls fully closed, it could be that your door needs adjustment and/or your door and glass seals need replacement. Your door seal will compress over time which will cause poor door sealing, to fix this the door will need to be adjusted to create a tighter seal. In addition, door and glass seals can deteriorate with use and allow air to leak into the heater, this will also cause the fire to burn too quickly. If this occurs, the door and or glass seals will need to be replaced. Refer to your heaters operating manual for instructions on how to adjust your door and replace your seals.

The firebricks only need to be replaced if they have disintegrated and are exposing the walls of the firebox. They do not need to be replaced if they have cracks in them providing they stay in place. The firebricks not only protect the sides of the firebox but also increase the thermal mass and the internal temperatures of the firebox.

  • Inspect the flue for any creosote/soot build up on the inside of the flue pipe. This can be done by removing the baffle plate/s inside the top of the firebox and checking the flue with a mirror and a torch. Have your flue cleaned if necessary by a qualified flue cleaning service.
  • Check that the door and glass seals are in good condition – replace if necessary.
  • Replace any firebricks that may have deteriorated and exposed the steel firebox.
  • Check baffle plate/s for soundness and replace if necessary.

  • If you are getting water running down the outside of your ceiling box and dripping onto your heater it is more than likely there is an issue with your roof flashing. Inspect and repair or replace your roof flashing. 
  • If you are getting water running down the inside of your active flue, into the firebox, it is probably an indication there is an issue with the cowl on top of your flue system. Inspect, repair or replace the cowl.