Correctly installing a gas ducted heater.
In the photos and the short movie, you will see a yellow flame. This flame is a soot-producing flame. With our modern tubular heat exchangers, everything has to be right to produce a beautiful BLUE flame.
In this particular case, the external gas ducted heater is running on LPG fuel. With gas bottles, a lot of people do not know that the bottle regulator has to be changed every 5 years. The spring tension drops off and it stops supply the correct pressure to the appliances, this drop in pressure has caused the gas valve to drop in burner pressure, then over time the flames change colour and burn yellow. This yellow flame then produces carbon or soot which blocks the secondary heat exchanger. This blockage then creates a secondary reason for the yellow flames and a lack of heat generated to the exchanger and the house.