The most important case is bringing suitable amount of air for combustion. Air must be provided in minimal amount that ensures full combustion of the coal and at the same time doesn’t cause spontaneous combustion of the gasses formed from heating of the fuel. Correct colour and propagation of the flame:

• Flame is yellow and it propagates up and on the sides
• White flame means that air flow is too big
• Red smoking flame is a sign that air flow is too little

Tapping on the water grates in a charging boiler is a sign of local heating water above the boiling point. Such occurrence is caused by weak circulation of water. What should one do to eliminate this?

• Installation doesn’t’ feature a CH circulation pumps
• If you own circulation pump increase its operation range or change the pump for a bigger one (e.g. in case when installation area is bigger from the one assumed by manufacturer for a given power of the pomp)
• Change the way of firing up for a slower one at which there’s lower temperature of exhaust fumes
• Check if the boiler is levelled (with deviation from the vertical, there may take place an uneven distribution of water in the boiler)

During a break in the work of blowing of the boiler being fired up, the temperature of the hearth is decreasing below the temperature of ignition of the gasses secreted by the fuel, making their concentration in the combustion chamber increase. Renewed inclusion of the fan causes an increase of temperature of ignition of the gasses in short period of time (above 300-400 degrees Celsius) which causes their sudden ignition. Combustion of accumulated gasses increases the pressure which effects in an explosion.

• Incorrect stack effect
• Bad quality of the fuel
• Too low frequency of the blow-off cycles
• No heat reception
• Turned off or suppressed by the thermostatic valves heat receivers
• Installation or boiler with build-up air
• Boiler incorrectly chosen for the usable area
• Inadequately set parameters of the boiler controller

The unburned fuel effect may occur because of too small amount of air in the combustion chamber. One should increase an amount of the air by 3-3% leaps and observe the quality of combustion. Other possible causes of the problem:

• Bad parameters (quality) of the fuel (change the fuel)
• Uneven blowing caused by the leakage of the chamber (tighten the hearth plate or clean the blower holes in the burner)

Reasons:

• Low quality fuel
• High humidity of the fuel
• Too big amount of fuel and incorrect course of the combustion process
• Low boiler operating temperatures

One must not rapidly let a cold water or pour the hearth with water. RISK OF BOILER EXPLOSION! To lower the temperature on the boiler one should:

• Close the air supply to the combustion chamber
• Close the flap with which the boiler sucks up the air and in case of a boiler with the blowing – aperture on the fan
• Remove the fuel from the hearth
• Tilt the cleaning hole located behind the hearth

NO!!! Refilling the water in CH system on hot boiler poses a very great danger of unsealing of the boiler and heating installation. Refilling the water to the installation during the work of the boiler is unacceptable and forbidden, especially when the boiler is strongly warmed-up, because in this way one may cause its permanent damage. Water can be refilled only during a downtime of operation of the boiler. If cavities occur for example as a result of installation leakage, those should be sealed immediately, because it poses a danger of scale deposing, which in turn leads to boiler damage.